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Darwiniana; Essays and Reviews Pertaining to Darwinism

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Title: Darwiniana; Essays and Reviews Pertaining to Darwinism

Author: Asa Gray


        
Release date: March 1, 2004 [eBook #5273]
                Most recently updated: June 15, 2026

Language: English

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*** START OF THE PROJECT GUTENBERG EBOOK DARWINIANA; ESSAYS AND REVIEWS PERTAINING TO DARWINISM ***




DARWINIANA

ESSAYS AND REVIEWS PERTAINING
TO DARWINISM

BY
ASA GRAY
FISHER PROFESSOR OF NATURAL HISTORY (BOTANY) IN
HARVARD UNIVERSITY

NEW YORK:
1876.









CONTENTS

DARWINIANA


PREFACE

ARTICLE I

THE ORIGIN OF SPECIES BY
MEANS OF NATURAL SELECTION

Views and Definitions of Species--How Darwin's differs from that of Agassiz,
and from the Common View--Variation, its Causes unknown.--Darwin's
Genealogical Tree--Darwin and Agassiz agree in the Capital
Facts--Embryology--Physical Connection of Species compatible with
Intellectual Connection--How to prove Transmutation.--Known Extent of
Variation--Cause of Likeness unknown--Artificial
Selection.--Reversion--Interbreeding--Natural Selection.--Classification
tentative.--What Darwin assumes.--Argument stated.--How Natural Selection
works.--Where the Argument is weakest.--Objections--Morphology and
Teleology harmonized.--Theory not atheistical.--Conceivable Modes of
Relation of God to Nature


ARTICLE II

DESIGN VERSUS NECESSITY--
A DISCUSSION

How Design in Nature can be shown--Design not inconsistent with Indirect
Attainment


ARTICLE III

NATURAL SELECTION NOT INCONSISTENT
WITH NATURAL THEOLOGY

PART I.--Premonitions of Darwinism.--A Proper Subject for
Speculation.--Summary of Facts and Ideas suggestive of Hypotheses of
Derivation

Part II--Limitations of Theory conceded by Darwin.--What Darwinism
explains.--Geological Argument strong in the Tertiary Period.--
Correspondence between Rank and Geological Succession--Difficulties in
Classification.--Nature of Affinity.--No Absolute Distinction between
Vegetable and Animal Kingdoms.--Individuality.--Gradation

PART III.--Theories contrasted.--Early Arguments against
Darwinism.--Philosophical and Theological Objections--Theory may be
theistic.--Final Cause not excluded.--Cause of Variation unknown.--Three
Views of Efficient Cause compatible with Theism.--Agassiz's Objections of a
Philosophical Nature.--Minor Objections.--Conclusion


ARTICLE IV

SPECIES AS TO VARIATION,
GEOGRAPHICAL DISTRIBUTION,
AND SUCCESSION

Alphonse De Candolle's Study of the Oak Genus.--Variability of the
Species.--Antiquity.--A Common Origin probable.--Dr. Falconer on the Common
Origin of Elephants--Variation and Natural Selection
distinguished.--Saporta on the Gradation between the Vegetable Forms of the
Cretaceous and the Tertiary.--Hypothesis of Derivation more likely to be
favored by Botanists than by Zoologists.--Views of Agassiz respecting the
Origin, Dispersion, Variation, Characteristics, and Successive Creation of
Species contrasted with those of De Candolle and others--Definition of
Species--Whether its Essence is in the Likeness
or in the Genealogical Connection of the Individuals composing a Species


ARTICLE V

SEQUOIA AND ITS HISTORY:
THE RELATIONS OF NORTH AMERICAN
TO NORTHEAST ASIAN AND TO
TERTIARY VEGETATION

Age and Size of Sequoia.--Isolation.--Decadence.--Related Genera.-- Former
Distribution.--Similarity between the Flora of Japan and that of the United
States, especially on the Atlantic Side.--Former Glaciation as explaining
the Present Dispersion of Species.--This confirmed by the Arctic Fossil
Flora of the Tertiary Period.--Tertiary Flora derived from the Preceding
Cretaceous.--Order and Adaptation in Organic Nature likened to a
Flow.--Order implies an Ordainer


ARTICLE VI

THE ATTITUDE OF WORKING
NATURALISTS TOWARD DARWINISM

General Tendency to Acceptance of the Derivative Hypothesis noted.--Lyell,
Owen, Alphonse De Candolle, Bentham, Flower, Ailman.-- Dr. Dawson's "Story
of the Earth and Man" examined.--Difference between Scientific Men and
General Speculators or Amateurs in the
Use of Hypotheses


ARTICLE VII

EVOLUTION AND THEOLOGY

Writings of Henslow, Hodges, and Le Conte examined.--Evolution and Design
compatible.--The Admission of a System of Nature, with Fixed Laws, concedes
in Principle all that the Doctrine of Evolution requires.--Hypotheses,
Probabilities, and Surmises, not to be decried by Theologians, who use
them, perhaps, more freely and loosely than Naturalists.--Theologians risk
too much in the Defense of Untenable Outposts


ARTICLE VIII

"WHAT IS DARWINISM?"

Dr. Hodges Book with this Title criticised.--He declares that Darwinism is
Atheism, yet its Founder a Theist.--Darwinism founded, however, upon
Orthodox Conceptions, and opposed, not to Theism, but only to Intervention
in Nature, while the Key-note of Dr. Hedge's System is Interference.--Views
and Writings of St. Clair, Winchell, and Kingsley adverted to


ARTICLE IX

CHARLES DARWIN:
SKETCH ACCOMPANYING A PORTRAIT IN "NATURE"

Darwin's Characteristics and Work as a Naturalist compared with those of
Robert Brown.--His Illustration of the Principle that "Nature abhors Close
Fertilization. "--His Impression upon Natural History exceeded only by
Linnaeus.--His Service in restoring Teleology to Natural History


ARTICLE X

INSECTIVOROUS PLANTS

Classification marks Distinctions where Nature exhibits Gradations.--
Recovery of Forgotten Knowledge and History of what was known of Dionzea,
Drosera, and Sarracenia.


ARTICLE XI

INSECTIVOROUS AND CLIMBING PLANTS

Review of Darwin's Two Works upon these Subjects--No Absolute Marks for
distinguishing between Vegetables and Animals.--New observations upon the
Sundews or Droseras.--Their Sensitiveness, Movements, Discernment of the
Presence and Appropriation of Animal Matter.--Dionaea, and other Plants of
the same Order.--Utricularia and Pinguicula.--Sarracenia and
Nepenthes.--Climbing Plants; the Climbing effected through Sensitiveness or
Response to External Impression and Automatic Movement.--Capacities
inherent in Plants generally, and apparently of no Service to them,
developed and utilized by those which climb.--Natural Selection not a
Complete Explanation


ARTICLE XII

DURATION AND ORIGINATION OF
RACE AND SPECIES

PART I.--Do Varieties in Plants wear out, or tend to wear out?--The Question
considered in the Light of Facts, and in that of the Darwinian
Theory.--Conclusion that Races sexually propagated need not die of Old
Age.--This Conclusion inferred from the Provisions and Arrangements in
Nature to secure Cross-Fertilization of Individuals.-- Reference to Mr.
Darwin's Development of this View

PART II.--Do Species wear out, and, if not, why not?--Implication of the
Darwinian Theory that Species are unlimited in Existence.--Examination of
an Opposite Doctrine maintained by Naudin.--Evidence that Species may die
out from Inherent Causes only indirect and inferential from Arrangements to
secure Wide Breeding--Physiological Import of Sexes--Doubtful whether
Sexual Reproduction with Wide Breeding is a Preventive or only a Palliative
of Decrepitude in Species.-- Darwinian Hypothesis must suppose the Former


ARTICLE XIII

EVOLUTIONARY TELEOLOGY

The Opposition between Morphology and Teleology reconciled by Darwinism, and
the Latter reinstated--Character of the New Teleology.--Purpose and Design
distinguished--Man has no Monopoly of the Latter.--Inference of Design from
Adaptation and Utility legitimate; also in Hume's Opinion irresistible--The
Principle of Design, taken with Specific Creation, totally insufficient and
largely inapplicable; but, taken with the Doctrine of the Evolution of
Species in Nature, applicable, pertinent, and, moreover,
necessary.--Illustrations from Abortive Organs, supposed Waste of Being,
etc.--All Nature being of a Piece, Design must either pervade or be absent
from the Whole.--Its Absence not to be inferred because the Events take
place in Nature--Illustration of the Nature and Province of Natural
Selection.--It picks out, but does not originate Variations; these not a
Product of, but a Response to, the Environment; not physical, but
physiological--Adaptations in Nature not explained by Natural Selection
apart from Design or Final Cause--Absurdity of associating Design only with
Miracle--What is meant by Nature.--The Tradition of the DIVINE in Nature,
testified to by Aristotle, comes down to our Day with Undiminished Value



PREFACE

These papers are now collected at the request of friends and correspondents,
who think that they may be useful; and two new essays are added. Most of
the articles were written as occasion called for them within the past
sixteen years, and contributed to various periodicals, with little thought
of their forming a series, and none of ever bringing them together into a
volume, although one of them (the third) was once reprinted in a pamphlet
form. It is, therefore, inevitable that there should be considerable
iteration in the argument, if not in the language. This could not be
eliminated except by recasting the whole, which was neither practicable nor
really desirable. It is better that they should record, as they do, the
writer's freely-expressed thoughts upon the subject at the time; and to
many readers there may be some advantage in going more than once, in
different directions, over the same ground. If these essays were to be
written now, some things might be differently expressed or qualified, but
probably not so as to affect materially any important point. Accordingly,
they are here reprinted unchanged, except by a few merely verbal
alterations made in proof-reading, and the striking out of one or two
superfluous or immaterial passages. A very few additional notes or
references are appended.

To the last article but one a second part is now added, and the more
elaborate Article XIII is wholly new.

If it be objected that some of these pages are written in a lightness of
vein not quite congruous with the gravity of the subject and the
seriousness of its issues, the excuse must be that they were written with
perfect freedom, most of them as anonymous contributions to popular
journals, and that an argument may not be the less sound or an exposition
less effective for being playful. Some of the essays, however, dealing with
points of speculative scientific interest, may redress the balance, and be
thought sufficiently heavy if not solid.

To the objection likely to be made, that they cover only a part of the
ground, it can only be replied that they do not pretend to be systematic or
complete. They are all essays relating in some way or other to the subject
which has been, during these years, of paramount interest to naturalists,
and not much less so to most thinking people. The first appeared between
sixteen and seventeen years ago, immediately after the publication of
Darwin's "Origin of Species by Means of Natural Selection," as a review of
that volume, which, it was then foreseen, was to initiate a revolution in
general scientific opinion. Long before our last article was written, it
could be affirmed that the general doctrine of the derivation of species
(to put it comprehensively) has prevailed over that of specific creation,
at least to the extent of being the received and presumably in some sense
true conception. Far from undertaking any general discussion of evolution,
several even of Mr. Darwin's writings have not been noticed, and topics
which have been much discussed elsewhere are not here adverted to. This
applies especially to what may be called deductive evolution--a subject
which lay beyond the writer's immediate scope, and to which neither the
bent of his mind nor the line of his studies has fitted him to do justice.
If these papers are useful at all, it will be as showing how these new views
of our day are regarded by a practical naturalist, versed in one department
only (viz., Botany), most interested in their bearings upon its special
problems, one accustomed to direct and close dealings with the facts in
hand, and disposed to rise from them only to the consideration of those
general questions upon which they throw or from which they receive
illustration.

Then as to the natural theological questions which (owing to circumstances
needless now to be recalled or explained) are here throughout brought into
what most naturalists, and some other readers, may deem undue prominence,
there are many who may be interested to know how these increasingly
prevalent views and their tendencies are regarded by one who is
scientifically, and in his own fashion, a Darwinian, philosophically a
convinced theist, and religiously an acceptor of the "creed commonly called
the Nicene," as the exponent of the Christian faith.
"Truth emerges sooner from error than from confusion," says Bacon; and
clearer views than commonly prevail upon the points at issue regarding
"religion and science" are still sufficiently needed to justify these
endeavors.

BOTANIC GARDEN, CAMBRIDGE, MASS., June, 1876.

______________________________________



I

THE ORIGIN OF SPECIES BY MEANS OF

NATURAL SELECTION [I-1]

(American Journal of Science and Arts, March, 1860)



This book is already exciting much attention. Two American editions are
announced, through which it will become familiar to many of our readers,
before these pages are issued. An abstract of the argument--for "the whole
volume is one long argument," as the author states--is unnecessary in such
a case; and it would be difficult to give by detached extracts. For the
volume itself is an abstract, a prodromus of a detailed work upon which the
author has been laboring for twenty years, and which "will take two or
three more years to complete." It is exceedingly compact; and although
useful summaries are appended to the several chapters, and a general
recapitulation contains the essence of the whole, yet much of the aroma
escapes in the treble distillation, or is so concentrated that the flavor
is lost to the general or even to the scientific reader. The volume
itself--the proof-spirit--is just condensed enough for its purpose. It will
be far more widely read, and perhaps will make deeper impression, than the
elaborate work might have done, with all its full details of the facts upon
which the author's sweeping conclusions have been grounded. At least it is
a more readable book: but all the facts that can be mustered in favor of
the theory are still likely to be needed.

Who, upon a single perusal, shall pass judgment upon a work like this, to
which twenty of the best years of the life of a most able naturalist have
been devoted? And who among those naturalists who hold a position that
entitles them to pronounce summarily upon the subject, can be expected to
divest himself for the nonce of the influence of received and favorite
systems? In fact, the controversy now opened is not likely to be settled in
an off-hand way, nor is it desirable that it should be. A spirited conflict
among opinions of every grade must ensue, which--to borrow an illustration
from the doctrine of the book before us--may be likened to the conflict in
Nature among races in the struggle for life, which Mr. Darwin describes;
through which the views most favored by facts will be developed and tested
by "Natural Selection," the weaker ones be destroyed in the process, and
the strongest in the long-run alone survive.

The duty of reviewing this volume in the American Journal of Science would
naturally devolve upon the principal editor,' whose wide observation and
profound knowledge of various departments of natural history, as well as of
geology, particularly qualify him for the task. But he has been obliged to
lay aside his pen, and to seek in distant lands the entire repose from
scientific labor so essential to the restoration of his health--a
consummation devoutly to be wished, and confidently to be expected.
Interested as Mr. Dana would be in this volume, he could not be expected to
accept this doctrine.

Views so idealistic as those upon which his "Thoughts upon Species" [I-2]
are grounded, will not harmonize readily with a doctrine so thoroughly
naturalistic as that of Mr. Darwin. Though it is just possible that one who
regards the kinds of elementary matter, such as oxygen and hydrogen, and
the definite compounds of these elementary matters, and their compounds
again, in the mineral kingdom, as constituting species, in the same sense,
fundamentally, as that of animal and vegetable species, might admit an
evolution of one species from another in the latter as well as the former
case.

Between the doctrines of this volume and those of the other great
naturalist whose name adorns the title-page of this journal, the widest
divergence appears. It is interesting to contrast the two, and, indeed, is
necessary to our purpose; for this contrast brings out most prominently,
and sets in strongest light and shade, the main features of the theory of
the origination of species by means of Natural Selection.

The ordinary and generally-received view assumes the independent, specific
creation of each kind of plant and animal in a primitive stock, which
reproduces its like from generation to generation, and so continues the
species. Taking the idea of species from this perennial succession of
essentially similar individuals, the chain is logically traceable back to a
local origin in a single stock, a single pair, or a single individual, from
which all the individuals composing the species have proceeded by natural
generation. Although the similarity of progeny to parent is fundamental in
the conception of species, yet the likeness is by no means absolute; all
species vary more or less, and some vary remarkably--partly from the
influence of altered circumstances, and partly (and more really) from
unknown constitutional causes which altered conditions favor rather than
originate. But these variations are supposed to be mere oscillations from a
normal state, and in Nature to be limited if not transitory; so that the
primordial differences between species and species at their beginning have
not been effaced, nor largely obscured, by blending through variation.
Consequently, whenever two reputed species are found to blend in Nature
through a series of intermediate forms, community of origin is inferred,
and all the forms, however diverse, are held to belong to one species.
Moreover, since bisexuality is the rule in Nature (which is practically
carried out, in the long-run, far more generally than has been suspected),
and the heritable qualities of two distinct individuals are mingled in the
offspring, it is supposed that the general sterility of hybrid progeny
interposes an effectual barrier against the blending of the original
species by crossing.

From this generally-accepted view the well-known theory of Agassiz and the
recent one of Darwin diverge in exactly opposite directions.

That of Agassiz differs fundamentally from the ordinary view only in this,
that it discards the idea of a common descent as the real bond of union
among the individuals of a species, and also the idea of a local
origin--supposing, instead, that each species originated simultaneously,
generally speaking, over the whole geographical area it now occupies or has
occupied, and in perhaps as many individuals as it numbered at any
subsequent period.

Mr. Darwin, on the other hand, holds the orthodox view of the descent of
all the individuals of a species not only from a local birthplace, but from
a single ancestor or pair; and that each species has extended and
established itself, through natural agencies, wherever it could; so that
the actual geographical distribution of any species is by no means a
primordial arrangement, but a natural result. He goes farther, and this
volume is a protracted argument intended to prove that the species we
recognize have not been independently created, as such, but have descended,
like varieties, from other species. Varieties, on this view, are incipient
or possible species: species are varieties of a larger growth and a wider
and earlier divergence from the parent stock; the difference is one of
degree, not of kind.

The ordinary view--rendering unto Caesar the things that are
Caesar's--looks to natural agencies for the actual distribution and
perpetuation of species, to a supernatural for their origin.

The theory of Agassiz regards the origin of species and their present
general distribution over the world as equally primordial, equally
supernatural; that of Darwin, as equally derivative, equally natural.

The theory of Agassiz, referring as it does the phenomena both of origin
and distribution directly to the Divine will--thus removing the latter with
the former out of the domain of inductive science (in which efficient cause
is not the first, but the last word)--may be said to be theistic to excess.
The contrasted theory is not open to this objection. Studying the facts and
phenomena in reference to proximate causes, and endeavoring to trace back
the series of cause and effect as far as possible, Darwin's aim and
processes are strictly scientific, and his endeavor, whether successful or
futile, must be regarded as a legitimate attempt to extend the domain of
natural or physical science. For, though it well may be that "organic forms
have no physical or secondary cause," yet this can be proved only
indirectly, by the failure of every attempt to refer the phenomena in
question to causal laws. But, however originated, and whatever be thought
of Mr. Darwin's arduous undertaking in this respect, it is certain that
plants and animals are subject from their birth to physical influences, to
which they have to accommodate themselves as they can. How literally they
are "born to trouble," and how incessant and severe the struggle for life
generally is, the present volume graphically describes. Few will deny that
such influences must have gravely affected the range and the association of
individuals and species on the earth's surface. Mr. Darwin thinks that,
acting upon an inherent predisposition to vary, they have sufficed even to
modify the species themselves and produce the present diversity. Mr.
Agassiz believes that they have not even affected the geographical range
and the actual association of species, still less their forms; but that
every adaptation of species to climate, and of species to species, is as
aboriginal, and therefore as inexplicable, as are the organic forms
themselves.

Who shall decide between such extreme views so ably maintained on either
hand, and say how much of truth there may be in each? The present reviewer
has not the presumption to undertake such a task. Having no prepossession
in favor of naturalistic theories, but struck with the eminent ability of
Mr. Darwin's work, and charmed with its fairness, our humbler duty will be
performed if, laying aside prejudice as much as we can, we shall succeed in
giving a fair account of its method and argument, offering by the way a few
suggestions, such as might occur to any naturalist of an inquiring mind. An
editorial character for this article must in justice be disclaimed. The
plural pronoun is employed not to give editorial weight, but to avoid even
the appearance of egotism, and also the circumlocution which attends a
rigorous adherence to the impersonal style.

We have contrasted these two extremely divergent theories, in their broad
statements. It must not be inferred that they have no points nor ultimate
results in common.

In the first place, they practically agree in upsetting, each in its own
way, the generally-received definition of species, and in sweeping away the
ground of their objective existence in Nature. The orthodox conception of
species is that of lineal descent: all the descendants of a common parent,
and no other, constitute a species; they have a certain identity because of
their descent, by which they are supposed to be recognizable. So
naturalists had a distinct idea of what they meant by the term species, and
a practical rule, which was hardly the less useful because difficult to
apply in many cases, and because its application was indirect: that is, the
community of origin had to be inferred from the likeness; such degree of
similarity, and such only, being held to be con-specific as could be shown
or reasonably inferred to be compatible with a common origin. And the usual
concurrence of the whole body of naturalists (having the same data before
them) as to what forms are species attests the value of the rule, and also
indicates some real foundation for it in Nature. But if species were created
in numberless individuals over broad spaces of territory, these individuals
are connected only in idea, and species differ from varieties on the one
hand, and from genera, tribes, etc., on the other, only in degree; and no
obvious natural reason remains for fixing upon this or that degree as
specific, at least no natural standard, by which the opinions of different
naturalists may be correlated. Species upon this view are enduring, but
subjective and ideal. Any three or more of the human races, for example, are
species or not species, according to the bent of the naturalist's mind.
Darwin's theory brings us the other way to the same result. In his view,
not only all the individuals of a species are descendants of a common
parent, but of all the related species also. Affinity, relationship, all
the terms which naturalists use figuratively to express an underived,
unexplained resemblance among species, have a literal meaning upon Darwin's
system, which they little suspected, namely, that of inheritance. Varieties
are the latest offshoots of the genealogical tree in "an unlineal" order;
species, those of an earlier date, but of no definite distinction; genera,
more ancient species, and so on. The human races, upon this view, likewise
may or may not be species according to the notions of each naturalist as to
what differences are specific; but, if not species already, those races that
last long enough are sure to become so. It is only a question of time.

How well the simile of a genealogical tree illustrates the main ideas of
Darwin's theory the following extract from the summary of the fourth
chapter shows:

"It is a truly wonderful fact--the wonder of which we are apt to overlook
from familiarity--that all animals and all plants throughout all time and
space should be related to each other in group subordinate to group, in the
manner which we everywhere behold--namely, varieties of the same species
most closely related together, species of the same genus less closely and
unequally related together, forming sections and sub-genera, species of
distinct genera much less closely related, and genera related in different
degrees, forming sub-families, families, orders, sub-classes, and classes.
The several subordinate groups in any class cannot be ranked in a single
file, but seem rather to be clustered round points, and these round other
points, and so on in almost endless cycles. On the view that each species
has been independently created, I can see no explanation of this great fact
in the classification of all organic beings; but, to the best of my
judgment, it is explained through inheritance and the complex action of
natural selection, entailing extinction and divergence of character, as we
have seen illustrated in the diagram.

"The affinities of all the beings of the same class have sometimes been
represented by a great tree. I believe this simile largely speaks the truth.
The green and budding twigs may represent existing species; and those
produced during each former year may represent the long succession of
extinct species. At each period of growth all the growing twigs have tried
to branch out on all sides, and overtop and kill the surrounding twigs and
branches, in the same manner as species and groups of species have tried to
overmaster other species in the great battle for life. The limbs divided
into great branches, and these into lesser and lesser branches, were
themselves once, when the tree was small, budding twigs; and this
connection of the former and present buds by ramifying branches may well
represent the classification of all extinct and living species in groups
subordinate to groups. Of the many twigs which flourished when the tree was
a mere bush, only two or three, now grown into great branches, yet survive
and bear all the other branches; so with the species which lived during
long-past geological periods, very few now have living and modified
descendants. From the first growth of the tree, many a limb and branch has
decayed and dropped off; and these lost branches of various sizes may
represent those whole orders, families, and genera, which have now no
living representatives, and which are known to us only from having been
found in a fossil state. As we here and there see a thin, straggling branch
springing from a fork low down in a tree, and which by some chance has been
favored and is still alive on its summit, so we occasionally see an animal
like the Ornithorhynchus or Lepidosiren, which in some small degree
connects by its affinities two large branches of life, and which has
apparently been saved from fatal competition by having inhabited a protected
station. As buds give rise by growth to fresh buds, and these, if vigorous,
branch out and overtop on all sides many a feebler branch, so by generation
I believe it has been with the great Tree of Life, which fills with its
dead and broken branches the crust of the earth, and covers the surface
with its ever-branching and beautiful ramification."


It may also be noted that there is a significant correspondence between the
rival theories as to the main facts employed. Apparently every capital fact
in the one view is a capital fact in the other. The difference is in the
interpretation. To run the parallel ready made to our hands: [I-4]


"The simultaneous existence of the most diversified types under identical
circumstances . . . the repetition of similar types under the most
diversified circumstances . . . the unity of plan in otherwise
highly-diversified types of animals . . . the correspondence, now generally
known as special homologies, in the details of structure otherwise entirely
disconnected, down to the most minute peculiarities . . . the various
degrees and different kinds of relationship among animals which (apparently)
can have no genealogical connection . . . the simultaneous existence in the
earliest geological periods, . . . of representatives of all the great
types of the animal kingdom . . . the gradation based upon complications of
structure which may be traced among animals built upon the same plan; the
distribution of some types over the most extensive range of surface of the
globe, while others are limited to particular geographical areas . . . the
identity of structures of these types, notwithstanding their wide
geographical distribution . . . the community of structure in certain
respects of animals otherwise entirely different, but living within the
same geographical area . . . the connection by series of special structures
observed in animals widely scattered over the surface of the globe . . .
the definite relations in which animals stand to the surrounding world, . .
. the relations in which individuals of the same species stand to one
another . . . the limitation of the range of changes which animals undergo
during their growth . . . the return to a definite norm of animals which
multiply in various ways . . . the order of succession of the different
types of animals and plants characteristic of the different geological
epochs, . . . the localization of some types of animals upon the same points
of the surface of the globe during several successive geological periods . .
. the parallelism between the order of succession of animals and plants in
geological times, and the gradation among their living representatives . .
. the parallelism between the order of succession of animals in geological
times and the changes their living representatives undergo during their
embryological growth, [I-5] . . . the combination in many extinct types of
characters which in later ages appear disconnected in different types, . .
. the parallelism between the gradation among animals and the changes they
undergo during their growth, . . . the relations existing between these
different series and the geographical distribution of animals, . . . the
connection of all the known features of Nature into one system--"


In a word, the whole relations of animals, etc., to surrounding Nature and
to each other, are regarded under the one view as ultimate facts, or in the
ultimate aspect, and interpreted theologically; under the other as complex
facts, to be analyzed and interpreted scientifically. The one naturalist,
perhaps too largely assuming the scientifically unexplained to be
inexplicable, views the phenomena only in their supposed relation to the
Divine mind. The other, naturally expecting many of these phenomena to be
resolvable under investigation, views them in their relations to one
another, and endeavors to explain them as far as he can (and perhaps
farther) through natural causes.

But does the one really exclude the other? Does the investigation of
physical causes stand opposed to the theological view and the study of the
harmonies between mind and Nature? More than this, is it not most
presumable that an intellectual conception realized in Nature would be
realized through natural agencies? Mr. Agassiz answers these questions
affirmatively when he declares that "the task of science is to investigate
what has been done, to inquire if possible how it has been done, rather
than to ask what is possible for the Deity, since we can know that only by
what actually exists;" and also when he extends the argument for the
intervention in Nature of a creative mind to its legitimate application in
the inorganic world; which, he remarks, "considered in the same light,
would not fail also to exhibit unexpected evidence of thought, in the
character of the laws regulating the chemical combinations, the action of
physical forces, etc., etc." [I-6] Mr. Agassiz, however, pronounces that
"the connection between the facts is only intellectual"--an opinion which
the analogy of the inorganic world, just referred to, does not confirm, for
there a material connection between the facts is justly held to be
consistent with an intellectual--and which the most analogous cases we can
think of in the organic world do not favor; for there is a material
connection between the grub, the pupa, and the butterfly, between the
tadpole and the frog, or, still better, between those distinct animals
which succeed each other in alternate and very dissimilar generations. So
that mere analogy might rather suggest a natural connection than the
contrary; and the contrary cannot be demonstrated until the possibilities of
Nature under the Deity are fathomed.

But, the intellectual connection being undoubted, Mr. Agassiz properly
refers the whole to "the agency of Intellect as its first cause." In doing
so, however, he is not supposed to be offering a scientific explanation of
the phenomena. Evidently he is considering only the ultimate why, not the
proximate why or how.

Now the latter is just what Mr. Darwin is considering. He conceives of a
physical connection between allied species; but we suppose he does not deny
their intellectual connection, as related to a supreme intelligence.
Certainly we see no reason why he should, and many reasons why he should
not, Indeed, as we contemplate the actual direction of investigation and
speculation in the physical and natural sciences, we dimly apprehend a
probable synthesis of these divergent theories, and in it the ground for a
strong stand against mere naturalism. Even if the doctrine of the origin of
species through natural selection should prevail in our day, we shall not
despair; being confident that the genius of an Agassiz will be found equal
to the work of constructing, upon the mental and material foundations
combined, a theory of Nature as theistic and as scientific as that which he
has so eloquently expounded.

To conceive the possibility of "the descent of species from species by
insensibly fine gradations" during a long course of time, and to
demonstrate its compatibility with a strictly theistic view of the
universe, is one thing; to substantiate the theory itself or show its
likelihood is quite another thing. This brings us to consider what Darwin's
theory actually is, and how he supports it.

That the existing kinds of animals and plants, or many of them, may be
derived from other and earlier kinds, in the lapse of time, is by no means
a novel proposition. Not to speak of ancient speculations of the sort, it
is the well-known Lamarckian theory. The first difficulty which such
theories meet with is that in the present age, with all its own and its
inherited prejudgments, the whole burden of proof is naturally, and indeed
properly, laid upon the shoulders of the propounders; and thus far the
burden has been more than they could bear. From the very nature of the
case, substantive proof of specific creation is not attainable; but that of
derivation or transmutation of species may be. He who affirms the latter
view is bound to do one or both of two things: 1. Either to assign real and
adequate causes, the natural or necessary result of which must be to
produce the present diversity of species and their actual relations; or, 2.
To show the general conformity of the whole body of facts to such
assumption, and also to adduce instances explicable by it and inexplicable
by the received view, so perhaps winning our assent to the doctrine,
through its competency to harmonize all the facts, even though the cause of
the assumed variation remain as occult as that of the transformation of
tadpoles into frogs, or that of Coryne into Sarzia.

The first line of proof, successfully carried out, would establish
derivation as a true physical theory; the second, as a sufficient
hypothesis.

Lamarck mainly undertook the first line, in a theory which has been so
assailed by ridicule that it rarely receives the credit for ability to
which in its day it was entitled, But he assigned partly unreal, partly
insufficient causes; and the attempt to account for a progressive change in
species through the direct influence of physical agencies, and through the
appetencies and habits of animals reacting upon their structure, thus
causing the production and the successive modification of organs, is a
conceded and total failure. The shadowy author of the "Vestiges of the
Natural History of Creation" can hardly be said to have undertaken either
line, in a scientific way. He would explain the whole progressive evolution
of Nature by virtue of an inherent tendency to development, thus giving us
an idea or a word in place of a natural cause, a restatement of the
proposition instead of an explanation. Mr. Darwin attempts both lines of
proof, and in a strictly scientific spirit; but the stress falls mainly upon
the first, for, as he does assign real causes, he is bound to prove their
adequacy.

It should be kept in mind that, while all direct proof of independent
origination is attainable from the nature of the case, the overthrow of
particular schemes of derivation has not established the opposite
proposition. The futility of each hypothesis thus far proposed to account
for derivation may be made apparent, or unanswerable objections may be
urged against it; and each victory of the kind may render derivation more
improbable, and therefore specific creation more probable, without settling
the question either way. New facts, or new arguments and a new mode of
viewing the question, may some day change the whole aspect of the case. It
is with the latter that Mr. Darwin now reopens the discussion.

Having conceived the idea that varieties are incipient species, he is led
to study variation in the field where it shows itself most strikingly, and
affords the greatest facilities to investigation. Thoughtful naturalists
have had increasing grounds to suspect that a reexamination of the question
of species in zoology and botany, commencing with those races which man
knows most about, viz., the domesticated and cultivated races, would be
likely somewhat to modify the received idea of the entire fixity of
species. This field, rich with various but unsystematized stores of
knowledge accumulated by cultivators and breeders, has been generally
neglected by naturalists, because these races are not in a state of nature;
whereas they deserve particular attention on this very account, as
experiments, or the materials for experiments, ready to our hand. In
domestication we vary some of the natural conditions of a species, and thus
learn experimentally what changes are within the reach of varying conditions
in Nature. We separate and protect a favorite race against its foes or its
competitors, and thus learn what it might become if Nature ever afforded it
equal opportunities. Even when, to subserve human uses, we modify a
domesticated race to the detriment of its native vigor, or to the extent of
practical monstrosity, although we secure forms which would not be
originated and could not be perpetuated in free Nature, yet we attain wider
and juster views of the possible degree of variation. We perceive that some
species are more variable than others, but that no species subjected to the
experiment persistently refuses to vary; and that, when it has once begun
to vary, its varieties are not the less but the more subject to variation.
"No case is on record of a variable being ceasing to be variable under
cultivation." It is fair to conclude, from the observation of plants and
animals in a wild as well as domesticated state, that the tendency to vary
is general, and even universal. Mr. Darwin does "not believe that
variability is an inherent and necessary contingency, under all
circumstances, with all organic beings, as some authors have thought." No
one supposes variation could occur under all circumstances; but the facts
on the whole imply a universal tendency, ready to be manifested under
favorable circumstances. In reply to the assumption that man has chosen for
domestication animals and plants having an extraordinary inherent tendency
to vary, and likewise to withstand diverse climates, it is asked:


"How could a savage possibly know, when he first tamed an animal, whether
it would vary in succeeding generations and whether it would endure other
climates? Has the little variability of the ass or Guinea-fowl, or the
small power of endurance of warmth by the reindeer, or of cold by the
common camel, prevented their domestication? I cannot doubt that if other
animals and plants, equal in number to our domesticated productions, and
belonging to equally diverse classes and countries, were taken from a state
of nature, and could be made to breed for an equal number of generations
under domestication, they would vary on an average as largely as the parent
species of our existing domesticated productions have varied."


As to amount of variation, there is the common remark of naturalists that
the varieties of domesticated plants or animals often differ more widely
than do the individuals of distinct species in a wild state: and even in
Nature the individuals of some species are known to vary to a degree
sensibly wider than that which separates related species. In his
instructive section on the breeds of the domestic pigeon, our author
remarks that "at least a score of pigeons might be chosen which if shown to
an ornithologist, and he were told that they were wild birds, would
certainly be ranked by him as well-defined species. Moreover, I do not
believe that any ornithologist would place the English carrier, the
short-faced tumbler, the runt, the barb, pouter, and fantail, in the same
genus; more especially as in each of these breeds several truly-inherited
sub-breeds, or species, as he might have called them, could be shown him."
That this is not a case like that of dogs, in which probably the blood of
more than one species is mingled, Mr. Darwin proceeds to show, adducing
cogent reasons for the common opinion that all have descended from the wild
rock-pigeon. Then follow some suggestive remarks:


"I have discussed the probable origin of domestic pigeons at some, yet
quite insufficient, length; because when I first kept pigeons and watched
the several kinds, knowing well how true they bred, I felt fully as much
difficulty in believing that they could ever have descended from a common
parent as any naturalist could in coming to a similar conclusion in regard
to many species of finches, or other large groups of birds, in Nature. One
circumstance has struck me much; namely, that all the breeders of the
various domestic animals and the cultivators of plants, with whom I have
ever conversed, or whose treatises I have read, are firmly convinced that
the several breeds to which each has attended are descended from so many
aboriginally distinct species. Ask, as I have asked, a celebrated raiser of
Hereford cattle, whether his cattle might not have descended from
long-horns, and he will laugh you to scorn. I have never met a pigeon, or
poultry, or duck, or rabbit fancier, who was not fully convinced that each
main breed was descended from a distinct species. Van Mons, in his treatise
on pears and apples, shows how utterly he disbelieves that the several
sorts, for instance a Ribston-pippin or Codlin-apple, could ever have
proceeded from the seeds of the same tree. Innumerable other examples could
be given. The explanation, I think, is simple: from long-continued study
they arc strongly impressed with the differences between the several races;
and though they well know that each race varies slightly, for they win
their prizes by selecting such slight differences, yet they ignore all
general arguments, and refuse to sum up in their minds slight differences
accumulated during many successive generations. May not those naturalists
who, knowing far less of the laws of inheritance than does the breeder, and
knowing no more than he does of the intermediate links in the long lines of
descent, yet admit that many of our domestic races have descended from the
same parents--may they not learn a lesson of caution, when they deride the
idea of species in a state of nature being lineal descendants of other
species?"


The actual causes of variation are unknown. Mr. Darwin favors the opinion
of the late Mr. Knight, the great philosopher of horticulture, that
variability tinder domestication is somehow connected with excess of food.
He regards the unknown cause as acting chiefly upon the reproductive system
of the parents, which system, judging from the effect of confinement or
cultivation upon its functions, he concludes to be more susceptible than
any other to the action of changed conditions of life. The tendency to vary
certainly appears to be much stronger under domestication than in free
Nature. But we are not sure that the greater variableness of cultivated
races is not mainly owing to the far greater opportunities for
manifestation and accumulation--a view seemingly all the more favorable to
Mr. Darwin's theory. The actual amount of certain changes, such as size or
abundance of fruit, size of udder, stands of course in obvious relation to
supply of food.    Really, we no more know the reason why the progeny
occasionally deviates from the parent than we do why it usually resembles
it. Though the laws and conditions governing variation are known to a
certain extent, those governing inheritance are apparently inscrutable.
"Perhaps," Darwin remarks, "the correct way of viewing the whole subject
would be, to look at the inheritance of every character whatever as the
rule, and non-inheritance as the anomaly." This, from general and obvious
considerations, we have long been accustomed to do. Now, as exceptional
instances are expected to be capable of explanation, while ultimate laws
are not, it is quite possible that variation may be accounted for, while
the great primary law of inheritance remains a mysterious fact.

The common proposition is, that species reproduce their like; this is a
sort of general inference, only a degree closer to fact than the statement
that genera reproduce their like. The true proposition, the fact incapable
of further analysis, is, that individuals reproduce their like--that
characteristics are inheritable. So varieties, or deviations, once
originated, are perpetuable, like species. Not so likely to be perpetuated,
at the outset; for the new form tends to resemble a grandparent and a long
line of similar ancestors, as well as to resemble its immediate progenitors.
Two forces which coincide in the ordinary case, where the offspring
resembles its parent, act in different directions when it does not and it
is uncertain which will prevail. If the remoter but very potent ancestral
influence predominates, the variation disappears with the life of the
individual. If that of the immediate parent--feebler no doubt, but
closer--the variety survives in the offspring; whose progeny now has a
redoubled tendency to produce its own like; whose progeny again is almost
sure to produce its like, since it is much the same whether it takes after
its mother or its grandmother.

In this way races arise, which under favorable conditions may be as
hereditary as species. In following these indications, watching
opportunities, and breeding only from those individuals which vary most in
a desirable direction, man leads the course of variation as he leads a
streamlet--apparently at will, but never against the force of
gravitation--to a long distance from its source, and makes it more
subservient to his use or fancy. He unconsciously strengthens those
variations which he prizes when he plants the seed of a favorite fruit,
preserves a favorite domestic animal, drowns the uglier kittens of a
litter, and allows only the handsomest or the best mousers to propagate.
Still more, by methodical selection, in recent times almost marvelous
results have been produced in new breeds of cattle, sheep, and poultry, and
new varieties of fruit of greater and greater size or excellence.

It is said that all domestic varieties, if left to run wild, would revert
to their aboriginal stocks. Probably they would wherever various races of
one species were left to commingle. At least the abnormal or exaggerated
characteristics induced by high feeding, or high cultivation and prolonged
close breeding, would promptly disappear; and the surviving stock would
soon blend into a homogeneous result (in a way presently explained), which
would naturally be taken for the original form; but we could seldom know if
it were so. It is by no means certain that the result would be the same if
the races ran wild each in a separate region. Dr. Hooker doubts if there is
a true reversion in the case of plants. Mr. Darwin's observations rather
favor it in the animal kingdom. With mingled races reversion seems well
made out in the case of pigeons. The common opinion upon this subject
therefore probably has some foundation, But even if we regard varieties as
oscillations around a primitive centre or type, still it appears from the
readiness with which such varieties originate that a certain amount of
disturbance would carry them beyond the influence of the primordial
attraction, where they may become new centres of variation.

Some suppose that races cannot be perpetuated indefinitely even by keeping
up the conditions under which they were fixed; but the high antiquity of
several, and the actual fixity of many of them, negative this assumption.
"To assert that we could not breed our cart and race horses, long and short
horned cattle, and poultry of various breeds, for almost an infinite number
of generations, would be opposed to all experience."

Why varieties develop so readily and deviate so widely under domestication,
while they are apparently so rare or so transient in free Nature, may
easily be shown. In Nature, even with hermaphrodite plants, there is a vast
amount of cross-fertilization among various individuals of the same
species. The inevitable result of this (as was long ago explained in this
Journal [I-7]) is to repress variation, to keep the mass of a species
comparatively homogeneous over any area in which it abounds in individuals.
Starting from a suggestion of the late Mr. Knight, now so familiar, that
close interbreeding diminishes vigor and fertility; [I-8] and perceiving
that bisexuality is ever aimed at in Nature--being attained physiologically
in numerous cases where it is not structurally--Mr. Darwin has worked out
the subject in detail, and shown how general is the concurrence, either
habitual or occasional, of two hermaphrodite individuals in the
reproduction of their kind; and has drawn the philosophical inference that
probably no organic being self-fertilizes indefinitely; but that a cross
with another individual is occasionally--perhaps at very long
intervals--indispensable. We refer the reader to the section on the
intercrossing of individuals (pp. 96--101), and also to an article in the
Gardeners' Chronicle a year and a half ago, for the details of a very
interesting contribution to science, irrespective of theory.  In
domestication, this intercrossing may be prevented; and in this prevention
lies the art of producing varieties. But "the art itself is Nature," since
the whole art consists in allowing the most universal of all natural
tendencies in organic things (inheritance) to operate uncontrolled by other
and obviously incidental tendencies. No new power, no artificial force, is
brought into play either by separating the stock of a desirable variety so
as to prevent mixture, or by selecting for breeders those individuals which
most largely partake of the peculiarities for which the breed is valued.
{I-9]

We see everywhere around us the remarkable results which Nature may be said
to have brought about under artificial selection and separation. Could she
accomplish similar results when left to herself? Variations might begin, we
know they do begin, in a wild state. But would any of them be preserved and
carried to an equal degree of deviation? Is there anything in Nature which
in the long-run may answer to artificial selection? Mr. Darwin thinks that
there is; and Natural Selection is the key-note of his discourse,

As a preliminary, he has a short chapter to show that there is variation in
Nature, and therefore something for natural selection to act upon. He
readily shows that such mere variations as may be directly referred to
physical conditions (like the depauperation of plants in a sterile soil, or
their dwarfing as they approach an Alpine summit, the thicker fur of an
animal from far northward, etc.), and also those individual differences
which we everywhere recognize but do not pretend to account for, are not
separable by any assignable line from more strongly-marked varieties;
likewise that there is no clear demarkation between the latter and
sub-species, or varieties of the highest grade (distinguished from species
not by any known inconstancy, but by the supposed lower importance of their
characteristics); nor between these and recognized species. "These
differences blend into each other in an insensible series, and the series
impresses the mind with an idea of an actual passage."

This gradation from species downward is well made out. To carry it one step
farther upward, our author presents in a strong light the differences which
prevail among naturalists as to what forms should be admitted to the rank
of species. Some genera (and these in some countries) give rise to far more
discrepancy than others; and it is concluded that the large or dominant
genera are usually the most variable. In a flora so small as the British,
182 plants, generally reckoned as varieties, have been ranked by some
botanists as species. Selecting the British genera which include the most
polymorphous forms, it appears that Babington's Flora gives them 251
species, Bentham's only 112, a difference of 139 doubtful forms. These are
nearly the extreme views, but they are the views of two most capable and
most experienced judges, in respect to one of the best-known floras of the
world. The fact is suggestive, that the best-known countries furnish the
greatest number of such doubtful cases. Illustrations of this kind may be
multiplied to a great extent. They make it plain that, whether species in
Nature are aboriginal and definite or not, our practical conclusions about
them, as embodied in systematic works, are not facts but judgments, and
largely fallible judgments-

How much of the actual coincidence of authorities is owing to imperfect or
restricted observation, and to one naturalist's adopting the conclusions of
another without independent observation, this is not the place to consider.
It is our impression that species of animals are more definitely marked
than those of plants; this may arise from our somewhat extended
acquaintance with the latter, and our ignorance of the former. But we are
constrained by our experience to admit the strong likelihood, in botany,
that varieties on the one hand, and what are called closely-related species
on the other, do not differ except in degree. Whenever this wider
difference separating the latter can be spanned by intermediate forms, as
it sometimes is, no botanist long resists the inevitable conclusion.
Whenever, therefore, this wider difference can be shown to be compatible
with community of origin, and explained through natural selection or in any
other way, we are ready to adopt the probable conclusion; and we see
beforehand how strikingly the actual geographical association of related
species favors the broader view. Whether we should continue to regard the
forms in question as distinct species, depends upon what meaning we shall
finally attach to that term; and that depends upon how far the doctrine of
derivation can be carried back and how well it can be supported.

In applying his principle of natural selection to the work in hand, Mr.
Darwin assumes, as we have seen: i. Some variability of animals and plants
in nature; 2. The absence of any definite distinction between slight
variations, and varieties of the highest grade; 3. The fact that
naturalists do not practically agree, and do not increasingly tend to
agree, as to what forms are species and what are strong varieties, thus
rendering it probable that there may be no essential and original
difference, or no possibility of ascertaining it, at least in many cases;
also, 4. That the most flourishing and dominant species of the larger
genera on an average vary most (a proposition which can be substantiated
only by extensive comparisons, the details of which are not given); and, 5.
That in large genera the species are apt to be closely but unequally allied
together, forming little clusters round certain species--just such clusters
as would be formed if we suppose their members once to have been satellites
or varieties of a central or parent species, but to have attained at length
a wider divergence and a specific character. The fact of such association
is undeniable; and the use which Mr. Darwin makes of it seems fair and
natural.

The gist of Mr. Darwin's work is to show that such varieties are gradually
diverged into species and genera through natural selection; that natural
selection is the inevitable result of the struggle for existence which all
living things are engaged in; and that this struggle is an unavoidable
consequence of several natural causes, but mainly of the high rate at which
all organic beings tend to increase.

Curiously enough, Mr. Darwin's theory is grounded upon the doctrine of
Malthus and the doctrine of Hobbes. The elder DeCandolle had conceived the
idea of the struggle for existence, and, in a passage which would have
delighted the cynical philosopher of Malmesbury, had declared that all
Nature is at war, one organism with another or with external Nature; and
Lyell and Herbert had made considerable use of it.   But Hobbes in his theory
of society, and Darwin in his theory of natural history, alone have built
their systems upon it. However moralists and political economists may
regard these doctrines in their original application to human society and
the relation of population to subsistence, their thorough applicability to
the great society of the organic world in general is now undeniable. And to
Mr. Darwin belongs the credit of making this extended application, and of
working out the immensely diversified results with rare sagacity and
untiring patience. He has brought to view real causes which have been
largely operative in the establishment of the actual association and
geographical distribution of plants and animals. In this he must be allowed
to have made a very important contribution to an interesting department of
science, even if his theory fails in the endeavor to explain the origin or
diversity of species.  "Nothing is easier," says our author, "than to admit
in words the truth of the universal struggle for life, or more difficult--at
least I have found it so--than constantly to bear this conclusion in mind.
Yet, unless it be thoroughly ingrained in the mind, I am convinced that the
whole economy of Nature, with every fact on distribution, rarity,
abundance, extinction, and variation, will be dimly seen or quite
misunderstood. We behold the face of Nature bright with gladness, we often
see superabundance of food; we do not see, or we forget, that the birds
which are idly singing round us mostly live on insects or seeds, and are
thus constantly destroying life; or we forget how largely these songsters,
or their eggs, or their nestlings, are destroyed by birds and beasts of
prey; we do not always bear in mind that, though food may be now
superabundant, it is not so at all seasons of each recurring year."--(p.
62.)

"There is no exception to the rule that every organic being naturally
increases at so high a rate that, if not destroyed, the earth would soon be
covered by the progeny of a single pair. Even slow-breeding man has doubled
in twenty-five years, and at this rate, in a few thousand years, there
would literally not be standing-room for his progeny. Linnaeus has
calculated that if an annual plant produced only two seeds--and there is no
plant so unproductive as this--and their seedlings next year produced two,
and so on, then in twenty years there would be a million plants. The
elephant is reckoned to be the slowest breeder of all known animals, and I
have taken some pains to estimate its pro!)able minimum rate of natural
increase; it will be under the mark to assume that it breeds when thirty
years old, and goes on breeding till ninety years old, bringing forth three
pairs of young in this interval; if this be so, at the end of the fifth
century there would be alive fifteen million elephants, descended from the
first pair.

"But we have better evidence on this subject than mere theoretical
calculations, namely, the numerous recorded cases of the astonishingly
rapid increase of various animals in a state of nature, when circumstances
have been favorable to them during two or three following seasons. Still
more striking is the evidence from our domestic animals of many kinds which
have run wild in several parts of the world; if the statements of the rate
of increase of slow-breeding cattle and horses in South America, and
latterly in Australia, had not been well authenticated, they would have
been quite incredible. So it is with plants: cases could be given of
introduced plants which have become common throughout whole islands in a
period of less than ten years. Several of the plants now most numerous over
the wide plains of La Plata, clothing square leagues of surface almost to
the exclusion of all other plants, have been introduced from Europe; and
there are plants which now range in India, as I hear from Dr. Falconer,
from Cape Comorin to the Himalaya, which have been imported from America
since its discovery. In such cases, and endless instances could be given,
no one supposes that the fertility of these animals or plants has been
suddenly and temporarily increased in any sensible degree. The obvious
explanation is, that the conditions of life have been very favorable, and
that there has consequently been less destruction of the old and young, and
that nearly all the young have been enabled to breed. In such cases the
geometrical ratio of increase, the result of which never fails to be
surprising, simply explains the extraordinarily rapid increase and wide
diffusion of naturalized productions in their new homes."--(pp. 64, 65.)

"All plants and animals are tending to increase at a geometrical ratio; all
would most rapidly stock any station in which they could anyhow exist; the
increase must be checked by destruction at some period of life."--(p. 65.)


The difference between the most and the least prolific species is of no
account:


"The condor lays a couple of eggs, and the ostrich a score; and yet in the
same country the condor may be the more numerous of the two. The Fulmar
petrel lays but one egg, yet it is believed to be the most numerous bird in
the world."--(p. 68.)

"The amount of food gives the extreme limit to which each species can
increase; but very frequently it is not the obtaining of food, but the
serving as prey to other animals, which determines the average numbers of
species."--(p. 68.)

"Climate plays an important part in determining the average numbers of a
species, and periodical seasons of extreme cold or drought I believe to be
the most effective of all checks. I estimated that the winter of 1854--'55
destroyed four-fifths of the birds in my own grounds; and this is a
tremendous destruction, when we remember that ten per cent, is an
extraordinarily severe mortality from epidemics with man. The action of
climate seems at first sight to be quite independent of the struggle for
existence; but, in so far as climate chiefly acts in reducing food, it
brings on the most severe struggle between the individuals, whether of the
same or of distinct species, which subsist on the same kind of food, Even
when climate, for instance extreme cold, acts directly, it will be the
least vigorous, or those which have got least food through the advancing
winter, which will suffer most. When we travel from south to north, or from
a damp region to a dry, we invariably see some species gradually getting
rarer and rarer, and finally disappearing; and, the change of climate being
conspicuous, we are tempted to attribute the whole effect to its direct
action. But this is a very false view; we forget that each species, even
where it most abounds, is constantly suffering enormous destruction at some
period of its life, from enemies or from competitors for the same place and
food; and if these enemies or competitors be in the least degree favored by
any slight change of climate, they will increase in numbers, and, as each
area is already stocked with inhabitants, the other species will decrease.
When we travel southward and see a species decreasing in numbers, we may
feel sure that the cause lies quite as much in other species being favored
as in this one being hurt. So it is when we travel northward, but in a
somewhat lesser degree, for the number of species of all kinds, and
therefore of competitors, decreases northward; hence, in going northward,
or in ascending a mountain, we far oftener meet with stunted forms, due to
the directly injurious action of climate, than we do in proceeding
southward or in descending a mountain. When we reach the arctic regions, or
snow-capped summits, or absolute deserts, the struggle for life is almost
exclusively with the elements.

"That climate acts in main part indirectly by favoring other species, we
may clearly see in the prodigious number of plants in our gardens which can
perfectly well endure our climate, but which never become naturalized, for
they cannot compete with our native plants, nor resist destruction by our
native animals."--(pp. 68, 69.)


After an instructive instance in which "cattle absolutely determine the
existence of the Scotch fir," we are referred to cases in which insects
determine the existence of cattle:


"Perhaps Paraguay offers the most curious instance of this; for here
neither cattle, nor horses, nor dogs, have ever run wild, though they swarm
southward and northward in a feral state; and Azara and Rengger have shown
that this is caused by the greater number in Paraguay of a certain fly,
which lays its eggs in the navels of these animals when first born. The
increase of these flies, numerous as they are, must be habitually checked
by some means, probably by birds. Hence, if certain insectivorous birds
(whose numbers are probably regulated by hawks or beasts of prey) were to
increase in Paraguay, the flies would decrease--then cattle and horses
would become feral, and this would certainly greatly alter (as indeed I
have observed in parts of South America) the vegetation; this, again, would
largely affect the insects; and this, as we have just seen in
Staffordshire, the insectivorous birds, and so onward in ever-increasing
circles of complexity. We began this series by insectivorous birds, and we
had ended with them. Not that in Nature the relations can ever be as simple
as this. Battle within battle must ever be recurring with varying success;
and yet in the long-run the forces are so nicely balanced that the face of
Nature remains uniform for long periods of time, though assuredly the
merest trifle would often give the victory to one organic being over
another. Nevertheless, so profound is our ignorance, and so high our
presumption, that we marvel when we hear of the extinction of an organic
being; and as we do not see the cause, we invoke cataclysms to desolate the
world, or invent laws on the duration of the forms of life!"--(pp. 72, 73.)

"When we look at the plants and bushes clothing an entangled bank, we arc
tempted to attribute their proportional numbers and kinds to what we call
chance. But how false a view is this! Every one has heard that when an
American forest is cut down, a very different vegetation springs up; but it
has been observed that the trees now growing on the ancient Indian mounds,
in the Southern United States, display the same beautiful diversity and
proportion of kinds as in the surrounding virgin forests. What a struggle
between the several kinds of trees must here have gone on during long
centuries, each annually scattering its seeds by the thousand; what war
between insect and insect--between insects, snails, and other animals, with
birds and beasts of prey--all striving to increase, and all feeding on each
other or on the trees, or their seeds and seedlings, or on the other plants
which first clothed the ground and thus checked the growth of the trees!
Throw up a handful of feathers, and all must fall to the ground according
to definite laws; but how simple is this problem compared to the action and
reaction of the innumerable plants and animals which have determined, in the
course of centuries, the proportional numbers and kinds of trees now
growing on the old Indian ruins!"--(pp. 74, 75.)


For reasons obvious upon reflection, the competition is often, if not
generally, most severe between nearly related species when they are in
contact, so that one drives the other before it, as the Hanoverian the old
English rat, the small Asiatic cockroach in Russia, its greater congener,
etc. And this, when duly considered, explains many curious results; such,
for instance, as the considerable number of different genera of plants and
animals which are generally found to inhabit any limited area.


"The truth of the principle that the greatest amount of life can be
supported by great diversification of structure is seen under many natural
circumstances. In an extremely small area, especially if freely open to
immigration, and where the contest between individual and individual must
be severe, we always find great diversity in its inhabitants. For instance,
I found that a piece of turf, three feet by four in size, which had been
exposed for many years to exactly the same conditions, supported twenty
species of plants, and these belonged to eighteen genera, and to eight
orders, which showed how much these plants differed from each other. So it
is with the plants and insects on small and uniform islets; and so in small
ponds of fresh water. Farmers find that they can raise most food by a
rotation of plants belonging to the most different orders; Nature follows
what may be called a simultaneous rotation. Most of the animals and plants
which live close round any small piece of ground could live on it (supposing
it not to be in any way peculiar in its nature), and may be said to be
striving to the utmost to live there; but it is seen that, where they come
into the closest competition with each other, the advantages of
diversification of structure, with the accompanying differences of habit
and constitution, determine that the inhabitants, which thus jostle each
other most closely, shall, as a general rule, belong to what we call
different genera and orders."--(p. 114.)


The abundance of some forms, the rarity and final extinction of many
others, and the consequent divergence of character or increase of
difference among the surviving representatives, are other consequences. As
favored forms increase, the less favored must diminish in number, for there
is not room for all; and the slightest advantage, at first probably
inappreciable to human observation, must decide which shall prevail and
which must perish, or be driven to another and for it more favorable
locality.

We cannot do justice to the interesting chapter upon natural selection by
separated extracts. The following must serve to show how the principle is
supposed to work:


"If during the long course of ages, and under varying conditions of life,
organic beings vary at all in the several parts of their organization, and
I think this cannot be disputed; if there be, owing to the high geometrical
powers of increase of each species, at some age, season, or year, a severe
struggle for life, and this certainly cannot be disputed: then, considering
the infinite complexity of the relations of all organic beings to each
other and to their conditions of existence, causing an infinite diversity
in structure, constitution, and habits, to be advantageous to them, I think
it would be a most extraordinary fact if no variation ever had occurred
useful to each being's own welfare, in the same way as so many variations
have occurred useful to man. But if variations useful to any organic being
do occur, assuredly individuals thus characterized will have the best
chance of being preserved in the struggle for life; and from the strong
principle of inheritance they will tend to produce offspring similarly
characterized. This principle of preservation I have called, for the sake
of brevity, Natural Selection."--(pp. 126, 127.)


"In order to make it clear how, as I believe, natural selection acts, I
must beg permission to give one or two imaginary illustrations. Let us take
the case of a wolf, which preys on various animals, securing some by craft,
some by strength, and some by fleetness; and let us suppose that the
fleetest prey, a deer for instance, had from any change in the country
increased in numbers, or that other prey had decreased in numbers, during
that season of the year when the wolf is hardest pressed for food. I can
under such circumstances see no reason to doubt that the swiftest and
slimmest wolves would have the best chance of surviving, and so be
preserved or selected--provided always that they retained strength to
master their prey at this or at some other period of the year, when they
might be compelled to prey on other animals. I can see no more reason to
doubt this than that man can improve the fleetness of his greyhounds by
careful and methodical selection, or by that unconscious selection which
results from each man trying to keep the best dogs without any thought of
modifying the breed.

"Even without any change in the proportional numbers of the animals on
which our wolf preyed, a cub might be born with an innate tendency to
pursue certain kinds of prey. Nor can this be thought very improbable; for
we often observe great differences in the natural tendencies of our
domestic animals: one cat, for instance, taking to catching rats, another
mice; one cat, according to Mr. St. John, bringing home winged game,
another hares or rabbits, and another hunting on marshy ground!, and almost
nightly catching woodcocks or snipes. The tendency to catch rats rather
than mice is known to be inherited. Now, if any slight innate change of
habit or of structure benefited an individual wolf, it would have the best
chance of surviving and of leaving offspring. Some of its young would
probably inherit the same habits or structure, and by the repetition of
this process a new variety might be formed which would either supplant or
coexist with the parent-form of wolf. Or, again, the wolves inhabiting a
mountainous district, and those frequenting the lowlands, would naturally
be forced to hunt different prey; and from a continued preservation of the
individuals best fitted for the two sites, two varieties might slowly be
formed. These varieties would cross and blend where they met; but to this
subject of intercrossing we shall soon have to return. I may add that,
according to Mr. Pierce, there are two varieties of the wolf inhabiting the
Catskill Mountains in the United States, one with a light greyhound-like
form, which pursues deer, and the other more bulky, with shorter legs,
which more frequently attacks the shepherd's flock."--(pp. 90, 91.)


We eke out the illustration here with a counterpart instance, viz., the
remark of Dr. Bachman that "the deer that reside permanently in the swamps
of Carolina are taller and longer-legged than those in the higher grounds."
[I-10]

The limits allotted to this article are nearly reached, yet only four of
the fourteen chapters of the volume have been touched. These, however,
contain the fundamental principles of the theory, and most of those
applications of it which are capable of something like verification,
relating as they do to the phenomena now occurring. Some of our extracts
also show how these principles are thought to have operated through the
long lapse of the ages. The chapters from the sixth to the ninth inclusive
are designed to obviate difficulties and objections, "some of them so grave
that to this day," the author frankly says, he "can never reflect on them
without being staggered." We do not wonder at it. After drawing what
comfort he can from "the imperfection of the geological record" (Chapter
IX), which we suspect is scarcely exaggerated, the author considers the
geological succession of organic beings (Chapter X), to see whether they
better accord with the common view of the immutability of species, or with
that of their slow and gradual modification. Geologists must settle that
question. Then follow two most interesting and able chapters on the
geographical distribution of plants and animals, the summary of which we
should be glad to cite; then a fitting chapter upon classification,
morphology, embryology, etc., as viewed in the light of this theory, closes
the argument; the fourteenth chapter being a recapitulation.

The interest for the general reader heightens as the author advances on his
perilous way and grapples manfully with the most formidable difficulties.

To account, upon these principles, for the gradual elimination and
segregation of nearly allied forms--such as varieties, sub-species, and
closely-related or representative species--also in a general way for their
geographical association and present range, is comparatively easy, is
apparently within the bounds of possibility. Could we stop here we should
be fairly contented. But, to complete the system, to carry out the
principles to their ultimate conclusion, and to explain by them many facts
in geographical distribution which would still remain anomalous, Mr. Darwin
is equally bound to account for the formation of genera, families, orders,
and even classes, by natural selection. He does "not doubt that the theory
of descent with modification embraces all the members of the same class,"
and he concedes that analogy would press the conclusion still further;
while he admits that "the more distinct the forms are, the more the
arguments fall away in force." To command assent we naturally require
decreasing probability to be overbalanced by an increased weight of
evidence. An opponent might plausibly, and perhaps quite fairly, urge that
the links in the chain of argument are weakest just where the greatest
stress falls upon them.

To which Mr. Darwin's answer is, that the best parts of the testimony have
been lost. He is confident that intermediate forms must have existed; that
in the olden times when the genera, the families, and the orders, diverged
from their parent stocks, gradations existed as fine as those which now
connect closely related species with varieties. But they have passed and
left no sign. The geological record, even if all displayed to view, is a
book from which not only many pages, but even whole alternate chapters,
have been lost out, or rather which were never printed from the autographs
of Nature. The record was actually made in fossil lithography only at
certain times and under certain conditions (i.e., at periods of slow
subsidence and places of abundant sediment); and of these records all but
the last volume is out of print; and of its pages only local glimpses have
been obtained. Geologists, except Lyell, will object to this--some of them
moderately, others with vehemence. Mr. Darwin himself admits, with a candor
rarely displayed on such occasions, that he should have expected more
geological evidence of transition than he finds, and that all the most
eminent paleontologists maintain the immutability of species.

The general fact, however, that the fossil fauna of each period as a whole
is nearly intermediate in character between the preceding and the
succeeding faunas, is much relied on. We are brought one step nearer to the
desired inference by the similar "fact, insisted on by all paleontologists,
that fossils from two consecutive formations are far more closely related
to each other than are the fossils of two remote formations. Pictet gives a
well-known instance--the general resemblance of the organic remains from the
several stages of the chalk formation, though the species are distinct at
each stage. This fact alone, from its generality, seems to have shaken
Prof. Pictet in his firm belief in the immutability of species" (p. 335).
What Mr. Darwin now particularly wants to complete his inferential evidence
is a proof that the same gradation may be traced in later periods, say in
the Tertiary, and between that period and the present; also that the later
gradations are finer, so as to leave it doubtful whether the succession is
one of species--believed on the one theory to be independent, on the other,
derivative--or of varieties, which are confessedly derivative. The proof of
the finer gradation appears to be forthcoming. Des Hayes and Lyell have
concluded that many of the middle Tertiary and a large proportion of the
later Tertiary mollusca are specifically identical with living species; and
this is still the almost universally prevalent view. But Mr. Agassiz states
that, "in every instance where he had sufficient materials, he had found
that the species of the two epochs supposed to be identical by Des Hayes
and Lyell were in reality distinct, although closely allied species."[I-11]
Moreover, he is now satisfied, as we understand, that the same gradation is
traceable not merely in each great division of the Tertiary, but in
particular deposits or successive beds, each answering to a great number of
years; where what have passed unquestioned as members of one species, upon
closer examination of numerous specimens exhibit differences which in his
opinion entitle them to be distinguished into two, three, or more species.
It is plain, therefore, that whatever conclusions can be fairly drawn from
the present animal and vegetable kingdoms in favor of a gradation of
varieties into species, or into what may be regarded as such, the same may
be extended to the Tertiary period. In both cases, what some call species
others call varieties; and in the later Tertiary shells this difference in
judgment affects almost half of the species!

We pass to a second difficulty in the way of Mr. Darwin's theory; to a case
where we are perhaps entitled to demand of him evidence of gradation like
that which connects the present with the Tertiary mollusca. Wide, very wide
is the gap, anatomically and physiologically (we do not speak of the
intellectual) between the highest quadrumana and man; and comparatively
recent, if ever, must the line have bifurcated. But where is there the
slightest evidence of a common progenitor? Perhaps Mr. Darwin would reply by
another question: where are the fossil remains of the men who made the
flint knives and arrowheads of the Somme Valley?

We have a third objection, one, fortunately, which has nothing to do with
geology. We can only state it here in brief terms. The chapter on hybridism
is most ingenious, able, and instructive. If sterility of crosses is a
special original arrangement to prevent the confusion of species by
mingling, as is generally assumed, then, since varieties cross readily and
their offspring is fertile inter se, there is a fundamental distinction
between varieties and species. Mr. Darwin therefore labors to show that it
is not a special endowment, but an incidental acquirement. He does show that
the sterility of crosses is of all degrees; upon which we have only to say,
Natura non facit saltum, here any more than elsewhere. But, upon his theory
he is bound to show how sterility might be acquired, through natural
selection or through something else. And the difficulty is, that, whereas
individuals of the very same blood tend to be sterile, and somewhat remoter
unions diminish this tendency, and when they have diverged into two
varieties the cross-breeds between the two are more fertile than either pure
stock--yet when they have diverged only one degree more the whole tendency
is reversed, and the mongrel is sterile, either absolutely or relatively.
He who explains the genesis of species through purely natural agencies
should assign a natural cause for this remarkable result; and this Mr.
Darwin has not done. Whether original or derived, however, this arrangement
to keep apart those forms which have, or have acquired (as the case may be),
a certain moderate amount of difference, looks to us as much designed for
the purpose, as does a rachet to prevent reverse motion in a wheel. If
species have originated by divergence, this keeps them apart.

Here let us suggest a possibly attainable test of the theory of derivation,
a kind of instance which Mr. Darwin may be fairly asked to produce--viz.,
an instance of two varieties, or what may be assumed as such, which have
diverged enough to reverse the movement, to bring out some sterility in the
crosses. The best marked human races might offer the most likely case. If
mulattoes are sterile or tend to sterility, as some naturalists confidently
assert, they afford Mr. Darwin a case in point. If, as others think, no
such tendency is made out, the required evidence is wanting.

A fourth and the most formidable difficulty is that of the production and
specialization of organs.

It is well said that all organic beings have been formed on two great laws:
unity of type, and adaptation to the conditions of existence.[I-12] The
special teleologists, such as Paley, occupy themselves with the latter
only; they refer particular facts to special design, but leave an
overwhelming array of the widest facts inexplicable. The morphologists
build on unity of type, or that fundamental agreement in the structure of
each great class of beings which is quite independent of their habits or
conditions of life; which requires each individual "to go through a certain
formality," and to accept, at least for a time, certain organs, whether
they are of any use to him or not. Philosophical minds form various
conceptions for harmonizing the two views theoretically. Mr. Darwin
harmonizes and explains them naturally. Adaptation to the conditions of
existence is the result of natural selection; unity of type, of unity of
descent. Accordingly, as he puts his theory, he is bound to account for the
origination of new organs, and for their diversity in each great type, for
their specialization, and every adaptation of organ to function and of
structure to condition, through natural agencies. Whenever he attempts this
he reminds us of Lamarck, and shows us how little light the science of a
century devoted to structural investigation has thrown upon the mystery of
organization. Here purely natural explanations fail. The organs being given,
natural selection may account for some improvement; if given of a variety
of sorts or grades, natural selection might determine which should survive
and where it should prevail.

On all this ground the only line for the theory to take is to make the most
of gradation and adherence to type as suggestive of derivation, and
unaccountable upon any other scientific view--deferring all attempts to
explain how such a metamorphosis was effected, until naturalists have
explained how the tadpole is metamorphosed into a frog, or one sort of
polyp into another. As to why it is so, the philosophy of efficient cause,
and even the whole argument from design, would stand, upon the admission of
such a theory of derivation, precisely where they stand without it. At
least there is, or need be, no ground of difference here between Darwin and
Agassiz. The latter will admit, with Owen and every morphologist, that
hopeless is the attempt to explain the similarity of pattern in members of
the same class by utility or the doctrine of final causes. "On the ordinary
view of the independent creation of each being, we can only say that so it
is, that it has so pleased the Creator to construct each animal and plant."
Mr. Darwin, in proposing a theory which suggests a how that harmonizes
these facts into a system, we trust implies that all was done wisely, in
the largest sense designedly, and by an intelligent first cause. The
contemplation of the subject on the intellectual side, the amplest
exposition of the unity of plan in creation, considered irrespective of
natural agencies, leads to no other conclusion.

We are thus, at last, brought to the question, What would happen if the
derivation of species were to be substantiated, either as a true physical
theory, or as a sufficient hypothesis? What would come of it? The inquiry
is a pertinent one, just now. For, of those who agree with us in thinking
that Darwin has not established his theory of derivation many will admit
with us that he has rendered a theory of derivation much less improbable
than before; that such a theory chimes in with the established doctrines of
physical science, and is not unlikely to be largely accepted long before it
can be proved. Moreover, the various notions that prevail--equally among
the most and the least religious--as to the relations between natural
agencies or phenomena and efficient cause, are seemingly more crude,
obscure, and discordant, than they need be.

It is not surprising that the doctrine of the book should be denounced as
atheistical. What does surprise and concern us is, that it should be so
denounced by a scientific man, on the broad assumption that a material
connection between the members of a series of organized beings is
inconsistent with the idea of their being intellectually connected with one
another through the Deity, i.e., as products of one mind, as indicating and
realizing a preconceived plan. An assumption the rebound of which is
somewhat fearful to contemplate, but fortunately one which every natural
birth protests against.

It would be more correct to say that the theory in itself is perfectly
compatible with an atheistic view of the universe. That is true; but it is
equally true of physical theories generally. Indeed, it is more true of the
theory of gravitation, and of the nebular hypothesis, than of the
hypothesis in question. The latter merely takes up a particular, proximate
cause, or set of such causes, from which, it is argued, the present
diversity of species has or may have contingently resulted. The author does
not say necessarily resulted; that the actual results in mode and measure,
and none other, must have taken place. On the other hand, the theory of
gravitation and its extension in the nebular hypothesis assume a universal
and ultimate physical cause, from which the effects in Nature must
necessarily have resulted. Now, it is not thought, at least at the present
day, that the establishment of the Newtonian theory was a step toward
atheism or pantheism. Yet the great achievement of Newton consisted in
proving that certain forces (blind forces, so far as the theory is
concerned), acting upon matter in certain directions, must necessarily
produce planetary orbits of the exact measure and form in which observation
shows them to exist--a view which is just as consistent with eternal
necessity, either in the atheistic or the pantheistic form, as it is with
theism.

Nor is the theory of derivation particularly exposed to the charge of the
atheism of fortuity; since it undertakes to assign real causes for
harmonious and systematic results. But, of this, a word at the close.

The value of such objections to the theory of derivation may be tested by
one or two analogous cases. The common scientific as well as popular belief
is that of the original, independent creation of oxygen and hydrogen, iron,
gold, and the like. Is the speculative opinion now increasingly held, that
some or all of the supposed elementary bodies are derivative or compound,
developed from some preceding forms of matter, irreligious? Were the old
alchemists atheists as well as dreamers in their attempts to transmute
earth into gold? Or, to take an instance from force (power)--which stands
one step nearer to efficient cause than form--was the attempt to prove that
heat, light, electricity, magnetism, and even mechanical power, are
variations or transmutations of one force, atheistical in its tendency? The
supposed establishment of this view is reckoned as one of the greatest
scientific triumphs of this century.

Perhaps, however, the objection is brought, not so much against the
speculation itself, as against the attempt to show how derivation might
have been brought about. Then the same objection applies to a recent
ingenious hypothesis made to account for the genesis of the chemical
elements out of the ethereal medium, and to explain their several atomic
weights and some other characteristics by their successive
complexity--hydrogen consisting of so many atoms of ethereal substance
united in a particular order, and so on. The speculation interested the
philosophers of the British Association, and was thought innocent, but
unsupported by facts. Surely Mr. Darwin's theory is none the worse,
morally, for having some foundation in fact.

In our opinion, then, it is far easier to vindicate a theistic character
for the derivative theory, than to establish the theory itself upon
adequate scientific evidence. Perhaps scarcely any philosophical objection
can be urged against the former to which the nebular hypothesis is not
equally exposed. Yet the nebular hypothesis finds general scientific
acceptance, and is adopted as the basis of an extended and recondite
illustration in Mr. Agassiz's great work.[I-13]

How the author of this book harmonizes his scientific theory with his
philosophy and theology, he has not informed us. Paley in his celebrated
analogy with the watch, insists that if the timepiece were so constructed
as to produce other similar watches, after a manner of generation in
animals, the argument from design would be all the stronger. What is to
hinder Mr. Darwin from giving Paley's argument a further a-fortiori
extension to the supposed case of a watch which sometimes produces better
watches, and contrivances adapted to successive conditions, and so at
length turns out a chronometer, a town clock, or a series of organisms of
the same type? From certain incidental expressions at the close of the
volume, taken in connection with the motto adopted from Whewell, we judge
it probable that our author regards the whole system of Nature as one which
had received at its first formation the impress of the will of its Author,
foreseeing the varied yet necessary laws of its action throughout the whole
of its existence, ordaining when and bow each particular of the stupendous
plan should be realized in effect, and--with Him to whom to will is to
do--in ordaining doing it, Whether profoundly philosophical or not, a view
maintained by eminent philosophical physicists and theologians, such as
Babbage on the one hand and Jowett on the other, will hardly be denounced
as atheism. Perhaps Mr. Darwin would prefer to express his idea in a more
general way, by adopting the thoughtful words of one of the most eminent
naturalists of this or any age, substituting the word action for "thought,"
since it is the former (from which alone the latter can be inferred) that
he has been considering. "Taking Nature as exhibiting thought for my guide,
it appears to me that while human thought is consecutive, Divine thought is
simultaneous, embracing at the same time and forever, in the past, the
present and the future, the most diversified relations among hundreds of
thousands of organized beings, each of which may present complications
again, which to study and understand even imperfectly--as for instance man
himself-- mankind has already spent thousands of years."[I-14] In thus
conceiving of the Divine Power in act as coetaneous with Divine Thought,
and of both as far as may be apart from the human element of time, our
author may regard the intervention of the Creator either as, humanly
speaking, done from all time, or else as doing through all time. In the
ultimate analysis we suppose that every philosophical theist must adopt one
or the other conception.

A perversion of the first view leads toward atheism, the notion of an
eternal sequence of cause and effect, for which there is no first cause--a
view which few sane persons can long rest in. The danger which may threaten
the second view is pantheism. We feel safe from either error, in our
profound conviction that there is order in the universe; that order
presupposes mind; design, will; and mind or will, personality. Thus
guarded, we much prefer the second of the two conceptions of causation, as
the more philosophical as well as Christian view--a view which leaves us
with the same difficulties and the same mysteries in Nature as in
Providence, and no other. Natural law, upon this view, is the human
conception of continued and orderly Divine action.

We do not suppose that less power, or other power, is required to sustain
the universe and carry on its operations, than to bring it into being. So,
while conceiving no improbability of "interventions of Creative mind in
Nature," if by such is meant the bringing to pass of new and fitting events
at fitting times, we leave it for profounder minds to establish, if they
can, a rational distinction in kind between his working in Nature carrying
on operations, and in initiating those operations.

We wished, under the light of such views, to examine more critically the
doctrine of this book, especially of some questionable parts; for instance,
its explanation of the natural development of organs, and its implication
of a "necessary acquirement of mental power" in the ascending scale of
gradation. But there is room only for the general declaration that we
cannot think the Cosmos a series which began with chaos and ends with mind,
or of which mind is a result: that, if, by the successive origination of
species and organs through natural agencies, the author means a series of
events which succeed each other irrespective of a continued directing
intelligence--events which mind does not order and shape to destined
ends--then he has not established that doctrine, nor advanced toward its
establishment, but has accumulated improbabilities beyond all belief. Take
the formation and the origination of the successive degrees of complexity
of eyes as a specimen. The treatment of this subject (pp. i88, 189), upon
one interpretation, is open to all the objections referred to; but, if, on
the other hand, we may rightly compare the eye "to a telescope, perfected
by the long-continued efforts of the highest human intellects," we could
carry out the analogy, and draw satisfactory illustrations and inferences
from it. The essential, the directly intellectual thing is the making of the
improvements in the telescope or the steam-engine. Whether the successive
improvements, being small at each step, and consistent with the general
type of the instrument, are applied to some of the individual machines, or
entire new machines are constructed for each, is a minor matter. Though, if
machines could engender, the adaptive method would be most economical; and
economy is said to be a paramount law in Nature. The origination of the
improvements, and the successive adaptations to meet new conditions or
subserve other ends, are what answer to the supernatural, and therefore
remain inexplicable. As to bringing them into use, though wisdom foresees
the result, the circumstances and the natural competition will take care of
that, in the long-run. The old ones will go out of use fast enough, except
where an old and simple machine remains still best adapted to a particular
purpose or condition--as, for instance, the old Newcomen engine for pumping
out coal-pits. If there's a Divinity that shapes these ends, the whole is
intelligible and reasonable; otherwise, not.

We regret that the necessity of discussing philosophical questions has
prevented a fuller examination of the theory itself, and of the interesting
scientific points which are brought to bear in its favor. One of its
neatest points, certainly a very strong one for the local origination of
species, and their gradual diffusion under natural agencies, we must
reserve for some other convenient opportunity.

The work is a scientific one, rigidly restricted to its direct object; and
by its science it must stand or fall. Its aim is, probably, not to deny
creative intervention in Nature--for the admission of the independent
origination of certain types does away with all antecedent improbability of
as much intervention as may be required--but to maintain that Natural
Selection, in explaining the facts, explains also many classes of facts
which thousand-fold repeated independent acts of creation do not explain,
but leave more mysterious than ever. How far the author has succeeded, the
scientific world will in due time be able to pronounce.

As these sheets are passing through the press, a copy of the second edition
has reached us. We notice with pleasure the insertion of an additional
motto on the reverse of the title page, directly claiming the theistic view
which we have vindicated for the doctrine. Indeed, these pertinent words of
the eminently wise Bishop Butler comprise, in their simplest expression,
the whole substance of our later pages:


"The only distinct meaning of the word 'natural' is stated, fixed, or
settled; since what is natural as much requires and presupposes an
intelligent mind to render it so, i.e., to effect it continually or at
stated times, as what is supernatural or miraculous does to effect it for
once."

II

DESIGN VERSUS NECESSITY

DISCUSSION BETWEEN TWO READERS
OF DARWIN'S TREATISE ON THE
ORIGIN OF SPECIES, UPON ITS
NATURAL THEOLOGY

(American Journal of Science and Arts, September, 1860)


D.T.--Is Darwin's theory atheistic or pantheistic? or, does it tend to
atheism or pantheism? Before attempting any solution of this question,
permit me to say a few words tending to obtain a definite conception of
necessity and design, as the sources from which events may originate, each
independent of the other; and we shall, perhaps, best attain a clear
understanding of each, by the illustration of an example in which simple
human designers act upon the physical powers of common matter.

Suppose, then, a square billiard-table to be placed with its corners
directed to the four cardinal points. Suppose a player, standing at the
north corner, to strike a red ball directly to the south, his design being
to lodge the ball in the south pocket; which design, if not interfered
with, must, of course be accomplished. Then suppose another player,
standing at the east corner, to direct a white ball to the west corner. This
design also, if not interfered with, must be accomplished. Next suppose both
players to strike their balls at the same instant, with like forces, in the
directions before given. In this case the balls would not pass as before,
namely, the red ball to the south, and the white ball to the west, but they
must both meet and strike each other in the centre of the table, and, being
perfectly elastic, the red ball must pass to the west pocket, and the white
ball to the south pocket. We may suppose that the players acted wholly
without concert with each other, indeed, they may be ignorant of each other'
s design, or even of each other's existence; still we know that the events
must happen as herein described. Now, the first half of the course of these
two balls is from an impulse, or proceeds from a power, acting from design.
Each player has the design of driving his ball across the table in a
diagonal line to accomplish its lodgment at the opposite corner of the
table. Neither designed that his ball should be deflected from that course
and pass to another corner of the table. The direction of this second part
of the motion must be referred entirely to necessity, which directly
interferes with the purpose of him who designed the rectilinear direction.
We are not, in this case, to go back to find design in the creation of the
powers or laws of inertia and elasticity, after the order of which the
deflection, at the instant of collision, necessarily takes place. We know
that these powers were inherent in the balls, and were not created to
answer this special deflection. We are required, by the hypothesis, to
confine attention in point of time, from the instant preceding the impact
of the balls, to the time of their arrival at the opposite corners of the
table. The cues aremoved by design. The impacts are acts from design. The
first half of the motion of each ball is under the direction of design. We
mean by this the particular design of each player. But, at the instant of
the collision of the balls upon each other, direction from design ceases,
and the balls no longer obey the particular designs of the players, the
ends or purposes intended by them are not accomplished, but frustrated, by
necessity, or by the necessary action of the powers of inertia and
elasticity, which are inherent in matter, and are not made by any design of
a Creator for this special action, or to serve this special purpose, but
would have existed in the materials of which the balls were made, although
the players had never been born.

I have thus stated, by a simple example in physical action, what is meant
by design and what by necessity; and that the latter may exist without any
dependence upon the former. If I have given the statement with what may be
thought, by some, unnecessary prolixity, I have only to say that I have
found many minds to have a great difficulty in conceiving of necessity as
acting altogether independent of design.

Let me now trace these principles as sources of action in Darwin's work or
theory. Let us see how much there is of design acting to produce a foreseen
end, and thus proving a reasoning and self-conscious Creator; and how much
of mere blind power acting without rational design, or without a specific
purpose or conscious foresight. Mr. Darwin has specified in a most clear
and unmistakable manner the operation of his three great powers, or rather,
the three great laws by which the organic power of life acts in the
formation of an eye. (See p. 169.) Following the method he has pointed out,
we will take a number of animals of the same species, in which the eye is
not developed. They may have all the other senses, with the organs of
nutrition, circulation, respiration, and locomotion. They all have a brain
and nerves, and some of these nerves may be sensitive to light; but have no
combination of retina, membranes, humors, etc., by which the distinct
image of an object may be formed and conveyed by the optic nerve to the
cognizance of the internal perception, or the mind. The animal in this case
would be merely sensible of the difference between light and darkness. He
would have no power of discriminating form, size, shape, or color, the
difference of objects, and to gain from these a knowledge of their being
useful or hurtful, friends or enemies. Up to this point there is no
appearance of necessity upon the scene. The billiard-balls have not yet
struck together, and we will suppose that none of the arguments that may be
used to prove, from this organism, thus existing, that it could not have
come into form and being without a creator acting to this end with
intelligence and design, are opposed by anything that can be found in
Darwin's theory; for, so far, Darwin's laws are supposed not to have come
into operation. Give the animals, thus organized, food and room, and they
may go on, from generation to generation, upon the same organic level. Those
individuals that, from natural variation, are born with light-nerves a
little more sensitive to light than their parents, will cross or interbreed
with those who have the same organs a little less sensitive, and thus the
mean standard will be kept up without any advancement. If our
billiard-table were sufficiently extensive, i. e., infinite, the balls
rolled from the corners would never meet, and the necessity which we have
supposed to deflect them would never act.

The moment, however, that the want of space or food commences natural
selection begins. Here the balls meet, and all future action is governed by
necessity. The best forms, or those nerves most sensitive to light,
connected with incipient membranes and humors for corneas and lenses, are
picked out and preserved by natural selection, of necessity. All cannot
live and propagate, and it is a necessity, obvious to all, that the weaker
must perish, if the theory be true. Working on, in this way, through
countless generations, the eye is at last


55

formed in all its beauty and excellence. It must (always assuming that this
theory is true) result from this combined action of natural variation, the
struggle for life, and natural selection, with as much certainty as the
balls, after collision, must pass to corners of the table different from
those to which they were directed, and so far forth as the eye is formed by
these laws, acting upward from the nerve merely sensitive to light, we can
no more infer design, and from design a designer, than we can infer design
in the direction of the billiard-balls after the collision. Both are
sufficiently accounted for by blind powers acting under a blind necessity.
Take away the struggle for life from the one, and the collision of the
balls from the other--and neither of these was designed--and the animal
would have gone on without eyes. The balls would have found the corners of
the table to which they were first directed.

While, therefore, it seems to me clear that one who can find no proof of
the existence of an intelligent Creator except through the evidence of
design in the organic world, can find no evidence of such design in the
construction of the eye, if it were constructed under the operation of
Darwin's laws, I shall not for one moment contend that these laws are
incompatible with design and a self-conscious, intelligent Creator. Such
design might, indeed, have coexisted with the necessity or natural
selection; and so the billiard-players might have designed the collision
of their balls; but neither the formation of the eye, nor the path of the
balls after collision, furnishes any sufficient proof of such design in
either case.

One, indeed, who believes, from revelation or any other cause, in the
existence of such a Creator, the fountain and Source of all things in
heaven above and in the earth beneath, will see in natural variation, the
struggle for life, and natural selection, only the order or mode in which
this Creator, in his own perfect wisdom, sees fit to act. Happy is he who
can thus see and adore. But how many are there who have no such


56

belief from intuition, or faith in revelation; but who have by careful and
elaborate search in the physical, and more especially in the organic world,
inferred, by induction, the existence of God from what has seemed to them
the wonderful adaptation of the different organs and parts of the animal
body to its, apparently, designed ends! Imagine a mind of this skeptical
character, in all honesty and under its best reason, after finding itself
obliged to reject the evidence of revelation, to commence a search after
the Creator, in the light of natural theology. He goes through the proof for
final cause and design, as given in a summary though clear, plain, and
convincing form, in the pages of Paley and the "Bridgewater Treatises." The
eye and the hand, those perfect instruments of optical and mechanical
contrivance and adaptation, without the least waste or surplusage--these,
say Paley and Bell, certainly prove a designing maker as much as the palace
or the watch proves an architect or a watchmaker. Let this mind, in this
state, cross Darwin's work, and find that, after a sensitive nerve or a
rudimentary hoof or claw, no design is to be found. From this point upward
the development is the mere necessary result of natural selection; and let
him receive this law of natural selection as true, and where does he find
himself? Before, he could refer the existence of the eye, for example, only
to design, or chance. There was no other alternative. He rejected chance,
as impossible.

It must then be a design. But Darwin brings up another power, namely,
natural selection, in place of this impossible chance. This not only may,
but, according to Darwin, must of necessity produce an eye. It may indeed
coexist with design, but it must exist and act and produce its results,
even without design. Will such a mind, under such circumstances, infer the
existence of the designer--God--when he can, at the same time,
satisfactorily account for the thing produced, by the operation of this
natural selection? It seems to me, therefore, perfectly evident


57


that the substitution of natural selection, by necessity, for design in the
formation of the organic world, is a step decidedly atheistical. It is in
vain to say that Darwin takes the creation of organic life, in its simplest
forms, to have been the work of the Deity. In giving up design in these
highest and most complex forms of organization, which have always been
relied upon as the crowning proof of the existence of an intelligent
Creator, without whose intellectual power they could not have been brought
into being, he takes a most decided step to banish a belief in the
intelligent action of God from the organic world. The lower organisms will
go next.

The atheist will say, Wait a little. Some future Darwin will show how the
simple forms came necessarily from inorganic matter. This is but another
step by which, according to Laplace, "the discoveries of science throw
final causes further back."

A.G.--It is conceded that, if the two players in the supposed case were
ignorant of each other's presence, the designs of both were frustrated, and
from necessity. Thus far it is not needful to inquire whether this
necessary consequence is an unconditional or a conditioned necessity, nor
to require a more definite statement of the meaning attached to the word
necessity as a supposed third alternative.

But, if the players knew of each other's presence, we could not infer from
the result that the design of both or of either was frustrated. One of them
may have intended to frustrate the other's design, and to effect his own.
Or both may have been equally conversant with the properties of the matter
and the relation of the forces concerned (whatever the cause, origin, or
nature, of these forces and properties), and the result may have been
according to the designs of both.

As you admit that they might or might not have designed the collision of
their balls and its consequences the question arises whether there is any
way of ascertaining which of the
two conceptions we may form about it is the true one. Now, let it be
remarked that design can never be demonstrated. Witnessing the act does not
make known the design, as we have seen in the case assumed for the basis of
the argument. The word of the actor is not proof; and that source of
evidence is excluded from the cases in question. The only way left, and the
only possible way in cases where testimony is out of the question, is to
infer the design from the result, or from arrangements which strike us as
adapted or intended to produce a certain result, which affords a
presumption of design. The strength of this presumption may be zero, or an
even chance, as perhaps it is in the assumed case; but the probability of
design will increase with the particularity of the act, the specialty of
the arrangement or machinery, and with the number of identical or yet more
of similar and analogous instances, until it rises to a moral certainty--i.
e., to a conviction which practically we are as unable to resist as we are
to deny the cogency of a mathematical demonstration. A single instance, or
set of instances, of a comparatively simple arrangement might suffice. For
instance, we should not doubt that a pump was designed to raise water by
the moving of the handle. Of course, the conviction is the stronger, or at
least the sooner arrived at, where we can imitate the arrangement, and
ourselves produce the result at will, as we could with a pump, and also with
the billiard-balls.

And here I would suggest that your billiard-table, with the case of
collision, answers well to a machine. In both a result is produced by
indirection--by applying a force out of line of the ultimate direction.
And, as I should feel as confident that a man intended to raise water who
was working a pumphandle, as if he were bringing it up in pailfuls from
below by means of a ladder, so, after due examination of the billiard-table
and its appurtenances, I should probably think it likely that the effect of
the rebound was expected and intended no less than that of the immediate
impulse. And a similar inspection of arrangements and results in Nature
would raise at least an equal presumption of design.

You allow that the rebound might have been intended, but you require proof
that it was. We agree that a single such instance affords no evidence
either way. But how would it be if you saw the men doing the same thing
over and over? and if they varied it by other arrangements of the balls or
of the blow, and these were followed by analogous results? How if you at
length discovered a profitable end of the operation, say the winning of a
wager? So in the counterpart case of natural selection: must we not infer
intention from the arrangements and the results? But I will take another
case of the very same sort, though simpler, and better adapted to
illustrate natural selection; because the change of direction--your
necessity--acts gradually or successively, instead of abruptly.
Suppose I hit a man standing obliquely in my rear, by throwing forward a
crooked stick, called a boomerang. How could he know whether the blow was
intentional or not? But suppose I had been known to throw boomerangs
before; suppose that, on different occasions, I had before wounded persons
by the same, or other indirect and apparently aimless actions; and suppose
that an object appeared to be gained in the result--that definite ends were
attained--would it not at length be inferred that my assault, though
indirect, or apparently indirect, was designed?

To make the case more nearly parallel with those it is brought to
illustrate, you have only to suppose that, although the boomerang thrown by
me went forward to a definite place, and at least appeared to subserve a
purpose, and the bystanders, after a while, could get traces of the mode or
the empirical law of its flight, yet they could not themselves do anything
with it. It was quite beyond their power to use it. Would they doubt, or
deny my intention, on that account? No: they would insist that design on my
part must be presumed from the nature of the results; that, though design
may have been wanting in any one case, yet the repetition of the result,
and from different positions and under varied circumstances, showed that
there must have been design.

Moreover, in the way your case is stated, it seems to concede the most
important half of the question, and so affords a presumption for the rest,
on the side of design. For you seem to assume an actor, a designer,
accomplishing his design in the first instance. You--a bystander--infer
that the player effected his design in sending the first ball to the pocket
before him. You infer this from observation alone. Must you not from a
continuance of the same observation equally infer a common design of the two
players in the complex result, or a design of one of them to frustrate the
design of the other? If you grant a designing actor, the presumption of
design is as strong, or upon continued observation of instances soon
becomes as strong, in regard to the deflection of the balls, or variation
of the species, as it was for the result of the first impulse or for the
production of the original animal, etc.

But, in the case to be illustrated, we do not see the player. We see only
the movement of the balls. Now, if the contrivances and adaptations
referred to really do "prove a designer as much as the palace or the watch
proves an architect or a watchmaker"--as Paley and Bell argue, and as your
skeptic admits, while the alternative is between design and chance--then
they prove it with all the proof the case is susceptible of, and with
complete conviction. For we cannot doubt that the watch had a watchmaker.
And if they prove it on the supposition that the unseen operator acted
immediately--i.e., that the player directly impelled the balls in the
directions we see them moving, I insist that this proof is not impaired by
our ascertaining that he acted mediately--i.e., that the present state or
form of the plants or animals, like the present position of the
billiard-balls, resulted from the collision of the individuals with one
another, or with the surroundings. The original impulse, which we once
supposed was in the line of the observed movement, only proves to have been
in a different direction; but the series of movements took place with a
series of results, each and all of them none the less determined, none the
less designed.

Wherefore, when, at the close, you quote Laplace, that "the discoveries of
science throw final causes farther back," the most you can mean is, that
they constrain us to look farther back for the impulse. They do not at all
throw the argument for design farther back, in the sense of furnishing
evidence or presumption that only the primary impulse was designed, and
that all the rest followed from chance or necessity.

Evidence of design, I think you will allow, everywhere is drawn from the
observation of adaptations and of results, and has really nothing to do with
anything else, except where you can take the word for the will. And in that
case you have not argument for design, but testimony. In Nature we have no
testimony; but the argument is overwhelming.

Now, note that the argument of the olden time--that of Paley, etc., which
your skeptic found so convincing--was always the argument for design in the
movement of the balls after deflection. For it was drawn from animals
produced by generation, not by creation, and through a long succession of
generations or deflections. Wherefore, if the argument for design is
perfect in the case of an animal derived from a long succession of
individuals as nearly alike as offspring is generally like parents and
grandparents, and if this argument is not weakened when a variation, or
series of variations, has occurred in the course, as great as any
variations we know of among domestic cattle, how then is it weakened by the
supposition, or by the likelihood, that the variations have been twice or
thrice as great as we formerly supposed, or because the variations have been
"picked out," and a few of them pre served as breeders of still other
variations, by natural selection?

Finally let it be noted that your element of necessity has to do, so far as
we know, only with the picking out and preserving of certain changing
forms, i. e., with the natural selection. This selection, you may say, must
happen under the circumstances. This is a necessary result of the collision
of the balls; and these results can be predicted. If the balls strike so
and so, they will be deflected so and so. But the variation itself is of
the nature of an origination. It answers well to the original impulse of the
balls, or to a series of such impulses. We cannot predict what particular
new variation will occur from any observation of the past. Just as the
first impulse was given to the balls at a point out of sight, so the
impulse which resulted in the variety or new form was given at a point
beyond observation, and is equally mysterious or unaccountable, except on
the supposition of an ordaining will. The parent had not the peculiarity of
the variety, the progeny has. Between the two is the dim or obscure region
of the formation of a new individual, in some unknown part of which, and in
some wholly unknown way, the difference is intercalated. To introduce
necessity here is gratuitous and unscientific; but here you must have it to
make your argument valid.

I agree that, judging from the past, it is not improbable that variation
itself may be hereafter shown to result from physical causes. When it is so
shown, you may extend your necessity into this region, but not till then.
But the whole course of scientific discovery goes to assure us that the
discovery of the cause of variation will be only a resolution of variation
into two factors: one, the immediate secondary cause of the changes, which
so far explains them; the other an unresolved or unexplained phenomenon,
which will then stand just where the product, variation, stands now, only
that it will be one step nearer to the efficient cause. This line of
argument appears to me so convincing, that I am bound to suppose that it
does not meet your case. Although you introduced players to illustrate what
design is, it is probable that you did not intend, and would not accept,
the parallel which your supposed case suggested. When you declare that the
proof of design in the eye and the hand, as given by Paley and Bell, was
convincing, you mean, of course, that it was convincing, so long as the
question was between design and chance, but that now another alternative is
offered, one which obviates the force of those arguments, and may account
for the actual results without design. I do not clearly apprehend this
third alternative.

Will you be so good, then, as to state the grounds upon which you conclude
that the supposed proof of design from the eye, or the hand, as it stood
before Darwin's theory was promulgated, would be invalidated by the
admission of this new theory?

D.T.--As I have ever found you, in controversy, meeting the array of your
opponent fairly and directly, without any attempt to strike the body of his
argument through an unguarded joint in the phraseology, I was somewhat
surprised at the course taken in your answer to my statement on Darwin's
theory. You there seem to suppose that I instanced the action of the
billiard balls and players as a parallel, throughout, to the formation of
the organic world. Had it occurred to me that such an application might be
supposed to follow legitimately from my introduction of this action, I
should certainly have stated that I did not intend, and should by no means
accede to, that construction. My purpose in bringing the billiard-table
upon the scene was to illustrate, by example, design and necessity, as
different and independent sources from which results, it might indeed be
identical results, may be derived All the conclusions, therefore, that you
have arrived at through this misconception or misapplication of my
illustration, I cannot take as an answer to the matter stated or intended
to be stated by me. Again, following this misconception, you suppose the
skeptic (instanced by me as revealing through the evidence of design,
exhibited in the structure of the eye, for its designer, God) as bringing to
the examination a belief in the existence of design in the construction of
the animals as they existed up to the moment when the eye was, according to
my supposition, added to the heart, stomach, brain, etc. By skeptic I, of
course, intended one who doubted the existence of design in every organic
structure, or at least required proof of such design. Now, as the watch may
be instanced as a more complete exhibition of design than a flint knife or
an hour-glass, I selected, after the example of Paley, the eye, as
exhibiting by its complex but harmonious arrangements a higher evidence of
design and a designer than is to be found in a nerve sensitive to light, or
any mere rudimentary part or organ. I could not mean by skeptic one who
believed in design so far as a claw, or a nerve sensitive to light, was
concerned, but doubted all above. For one who believes in design at all
will not fail to recognize it in a hand or an eye. But I need not extend
these remarks, as you acknowledge in the sequel to your argument that you
may not have suited it to the case as I have stated it.

You now request me to "state the grounds upon which I conclude that the
supposed proof of design from the eye and the hand, as it stood before
Darwin's theory was promulgated, is invalidated by the admission of that
theory." It seems to me that a sufficient answer to this question has
already been made in the last part of my former paper; but, as you request
it, I will go over the leading points as there given, with more minuteness
of detail.

Let us, then, suppose a skeptic, one who is yet considering and doubting of
the existence of God, having already concluded that the testimony from any
and all revelation is insufficient, and having rejected what is called the
a priori arguments brought forward in natural theology, and pertinaciously
insisted upon by Dr. Clark and others, turning as a last resource to the
argument from design in the organic world. Voltaire tells him that a palace
could not exist without an architect to design it. Dr. Paley tells him
that a watch proves the design of a watchmaker. He thinks this very
reasonable, and, although he sees a difference between the works of Nature
and those of mere human art, yet if he can find in any organic body, or
part of a body, the same adaptation to its use that he finds in a watch,
this truth will go very far toward proving, if it is not entirely
conclusive, that, in making it, the powers of life by which it grew were
directed by an intelligent, reasoning master. Under the guidance of Paley he
takes an eye, which, although an optical, and not a mechanical instrument
like the watch, is as well adapted to testify to design. He sees, first,
that the eye is transparent when every other part of the body is opaque.
Was this the result of a mere Epicurean or Lucretian "fortuitous concourse"
of living "atoms"? He is not yet certain it might not be so. Next he sees
that it is spherical, and that this convex form alone is capable of changing
the direction of the light which proceeds from a distant body, and of
collecting it so as to form a distinct image within its globe. Next he sees
at the exact place where this image must be formed a curtain of nerve-work,
ready to receive and convey it, or excite from it, in its own mysterious
way, an idea of it in the mind. Last of all, he comes to the crystalline
lens. Now, he has before learned that without this lens an eye would by the
aqueous and Vitreous humors alone form an image upon the retina, but this
image would be indistinct from the light not being sufficiently refracted,
and likewise from having a colored fringe round its edges. This last effect
is attributable to the refrangibility of light, that is, to some of the
colors being more refracted than others. He likewise knows that more than a
hundred years ago Mr. Dollond having found out, after many experiments,
that some kinds of glass have the power of dispersing light, for each degree
of its refraction, much more than other kinds, and that on the discovery of
this fact he contrived to make telescopes in which he passed the light
through two object-glasses successively, one of which he made of crown and
one of flint glass, so ground and adapted to each other that the greater
dispersion produced by the substance of one should be corrected by the
smaller dispersion of the other. This contrivance corrected entirely the
colored images which had rendered all previous telescopes very imperfect. He
finds in this invention all the elements of design, as it appeared in the
thought and action of a human designer. First, conjecture of certain laws
or facts in optics. Then, experiment proving these laws or facts. Then, the
contrivance and formation of an instrument by which those laws or facts
must produce a certain sought result.

Thus enlightened, our skeptic turns to his crystalline lens to see if he
can discover the work of a Dollond in this. Here he finds that an eye,
having a crystalline lens placed between the humors, not only refracts the
light more than it would be refracted by the humors alone, but that, in
this combination of humors and lens, the colors are as completely corrected
as in the combination of Dollond's telescope. Can it be that there was no
design, no designer, directing the powers of life in the formation of this
wonderful organ? Our skeptic is aware that, in the arts of man, great aid
has been, sometimes, given by chance, that is, by the artist or workman
observing some fortuitous combination, form, or action, around him. He has
heard it said that the chance arrangement of two pairs of spectacles, in
the shop of a Dutch optician, gave the direction


67

for constructing the first telescope. Possibly, in time, say a few
geological ages, it might in some optician's shop have brought about a
combination of flint and crown glass which, together, should have been
achromatic. But the space between the humors of the eye is not an optician'
s shop where object-glasses of all kinds, shapes, and sizes, are placed by
chance, in all manner of relations and positions. On the hypothesis under
which our skeptic is making his examination--the eye having been completed
in all but the formation of the lens--the place which the lens occupies
when completed was filled with parts of the humors and plane membrane,
homogeneous in texture and surface, presenting, therefore, neither the
variety of the materials nor forms which are contained in the optician's
shop for chance to make its combinations with. How, then, could it be cast
of a combination not before used, and fashioned to a shape different from
that before known, and placed in exact combination with all the parts
before enumerated, with many others not even mentioned? He sees no
parallelism of condition, then, by which chance could act in forming a
crystalline lens, which answers to the condition of an optician's shop,
where it might be possible in many ages for chance to combine existing forms
into an achromatic object-glass.

Considering, therefore, the eye thus completed and placed in its bony case
and provided with its muscles, its lids, its tear-ducts, and all its other
elaborate and curious appendages, and, a thousand times more wonderful
still, without being encumbered with a single superfluous or useless part,
can he say that this could be the work of chance? The improbability of this
is so great, and consequently the evidence of design is so strong, that he
is about to seal his verdict in favor of design, when he opens Mr. Darwin's
book.
There he finds that an eye is no more than a vital aggregation or growth,
directed, not by design nor chance, but moulded by natural variation and
natural selection, through which it must, necessarily, have been developed
and formed. Particles or atoms being aggregated by the blind powers of
life, must become under the given conditions, by natural variation and
natural selection, eyes, without design, as certainly as the red
billiard-ball went to the west pocket, by the powers of inertia and
elasticity, without the design of the hand that put it in motion. (See
Darwin, p. 169.)

Let us lay before our skeptic the way in which we may suppose that Darwin
would trace the operation of life, or the vital force conforming to these
laws. In doing this we need not go through with the formation of the
several membranes, humors, etc., but take the crystalline lens as the most
curious and nicely arranged and adapted of all the parts, and as giving,
moreover, a close parallel, in the end produced, to that produced by
design, by a human designer, Dollond, in forming his achromatic
object-glass. If it can be shown that natural variation and natural
selection were capable of forming the crystalline lens, it will not be
denied that they were capable of forming the iris, the sclerotica, the
aqueous humors, or any and all the other parts. Suppose, then, that we have
a number of animals, with eyes yet wanting the crystalline. In this state
the animals can see, but dimly and imperfectly, as a man sees after having
been couched. Some of the offspring of these animals have, by natural
variation, merely a portion of the membrane which separates the aqueous
from the vitreous humor a little thickened in its middle part, a little
swelled out. This refracts the light a little more than it would be
refracted by a membrane in which no such swelling existed, and not only so,
but, in combination with the humors, it corrects the errors of dispersion
and makes the image somewhat more colorless. All the young animals that
have this swelled membrane see more distinctly than their parents or
brethren. They, therefore, have an advantage over them in the struggle for
life. They can obtain food more easily; can find their prey, and escape
from their enemies with greater facility than their kindred. This thickening
and rounding of the membrane goes on from generation to generation by
natural variation; natural selection all the while "picking out with
unerring skill all the improvements, through countless generations," until
at length it is found that the membrane has become a perfect crystalline
lens. Now, where is the design in all this? The membrane was not thickened
and rounded to the end that the image should be more distinct and colorless;
but, being thickened and rounded by the operation of natural variation,
inherent in generation, natural selection of necessity produced the result
that we have seen. The same result was thus produced of necessity, in the
eye, that Dollond came at, in the telescope, with design, through painful
guessing, reasoning, experimenting, and forming.

Suppose our skeptic to believe in all this power of natural selection; will
he now seal up his verdict for design, with the same confidence that he
would before he heard of Darwin? If not, then "the supposed proof from
design is invalidated by Darwin's theory."

A.G.--Waiving incidental points and looking only to the gist of the
question, I remark that the argument for design as against chance, in the
formation of the eye, is most convincingly stated in your argument. Upon
this and upon numerous similar arguments the whole question we are
discussing turns. So, if the skeptic was about to seal his verdict in favor
of design, and a designer, when Darwin's book appeared, why should his
verdict now be changed or withheld? All the facts about the eye, which
convinced him that the organ was designed, remain just as they were. His
conviction was not produced through testimony or eyewitness, but design was
irresistibly inferred from the evidence of contrivance in the eye itself.

Now, if the eye as it is, or has become, so convincingly argued design why
not each particular step or part of this result? If the production of a
perfect crystalline lens in the eye--you know not how--as much indicated
design as did the production of a Dollond achromatic lens--you understand
how--then why does not "the swelling out" of a particular portion of the
membrane behind the iris--caused you know not how--which, by "correcting
the errors of dispersion and making the image somewhat more colorless,"
enabled the "young animals to see more distinctly than their parents or
brethren," equally indicate design--if not as much as a perfect
crystalline, or a Dollond compound lens, yet as much as a common
spectacle-glass?
Darwin only assures you that what you may have thought was done directly and
at once was done indirectly and successively. But you freely admit that
indirection and succession do not invalidate design, and also that Paley
and all the natural theologians drew the arguments which convinced your
skeptic wholly from eyes indirectly or naturally produced.

Recall a woman of a past generation and show her a web of cloth; ask her
how it was made, and she will say that the wool or cotton was carded, spun,
and woven by hand. When you tell her it was not made by manual labor, that
probably no hand has touched the materials throughout the process, it is
possible that she might at first regard your statement as tantamount to the
assertion that the cloth was made without design. If she did, she would not
credit your statement. If you patiently explained to her the theory of
carding-machines, spinning-jennies, and power-looms, would her reception of
your explanation weaken her conviction that the cloth was the result of
design? It is certain that she would believe in design as firmly as before,
and that this belief would be attended by a higher conception and reverent
admiration of a wisdom, skill, and power greatly beyond anything she had
previously conceived possible.

Wherefore, we may insist that, for all that yet appears, the argument for
design, as presented by the natural theologians, is just as good now, if we
accept Darwin's theory, as it was before that theory was promulgated; and
that the skeptical juryman, who was about to join the other eleven in a
unanimous verdict in favor of design, finds no good excuse for keeping the
court longer waiting.[II-1]



III

NATURAL SELECTION

NOT INCONSISTENT WITH

NATURAL THEOLOGY

(Atlantic Monthly for July, August, and October, 1860, reprinted in 1861)


I


Novelties are enticing to most people; to us they are simply annoying. We
cling to a long-accepted theory, just as we cling to an old suit of
clothes. A new theory, like a new pair of breeches (the Atlantic still
affects the older type of nether garment), is sure to have hard-fitting
places; or, even when no particular fault can be found with the article, it
oppresses with a sense of general discomfort. New notions and new styles
worry us, till we get well used to them, which is only by slow degrees.

Wherefore, in Galileo's time, we might have helped to proscribe, or to
burn--had he been stubborn enough to warrant cremation--even the great
pioneer of inductive research; although, when we had fairly recovered our
composure, and bad leisurely excogitated the matter, we might have come to
conclude that the new doctrine was better than the old one, after all, at
least for those who had nothing to unlearn.

Such being our habitual state of mind, it may well be believed that the
perusal of the new book "On the Origin of Species by Means of Natural
Selection" left an uncomfortable impression, in spite of its plausible and
winning ways. We were not wholly unprepared for it, as many of our
contemporaries seem to have been. The scientific reading in which we
indulge as a relaxation from severer studies had raised dim forebodings.
Investigations about the succession of species in time, and their actual
geographical distribution over the earth's surface, were leading up from all
sides and in various ways to the question of their origin. Now and then we
encountered a sentence, like Prof. Owen's "axiom of the continuous
operation of the ordained becoming of living things," which haunted us like
an apparition. For, dim as our conception must needs be as to what such
oracular and grandiloquent phrases might really mean, we felt confident that
they presaged no good to old beliefs. Foreseeing, yet deprecating, the
coming time of trouble, we still hoped that, with some repairs and
makeshifts, the old views might last out our days. Apres nous le deluge.
Still, not to lag behind the rest of the world, we read the book in which
the new theory is promulgated. We took it up, like our neighbors, and, as
was natural, in a somewhat captious frame of mind.

Well, we found no cause of quarrel with the first chapter. Here the author
takes us directly to the barn-yard and the kitchen-garden. Like an
honorable rural member of our General Court, who sat silent until, near the
close of a long session, a bill requiring all swine at large to wear pokes
was introduced, when he claimed the privilege of addressing the house, on
the proper ground that he had been "brought up among the pigs, and knew all
about them"--so we were brought up among cows and cabbages; and the lowing
of cattle, the cackle of hens, and the cooing of pigeons, were sounds native
and pleasant to our ears. So "Variation under Domestication" dealt with
familiar subjects in a natural way, and gently introduced "Variation under
Nature," which seemed likely enough. Then follows "Struggle for
Existence"--a principle which we experimentally know to be true and
cogent--bringing the comfortable assurance, that man, even upon Leviathan
Hobbes's theory of society, is no worse than the rest of creation, since all
Nature is at war, one species with another, and the nearer kindred the more
internecine--bringing in thousandfold confirmation and extension of the
Malthusian doctrine that population tends far to outrun means of
subsistence throughout the animal and vegetable world, and has to be kept
down by sharp preventive checks; so that not more than one of a hundred or a
thousand of the individuals whose existence is so wonderfully and so
sedulously provided for ever comes to anything, under ordinary
circumstances; so the lucky and the strong must prevail, and the weaker and
ill-favored must perish; and then follows, as naturally as one sheep
follows another, the chapter on "Natural Selection," Darwin's cheval de
bataille, which is very much the Napoleonic doctrine that Providence favors
the strongest battalions--that, since many more individuals are born than
can possibly survive, those individuals and those variations which possess
any advantage, however slight, over the rest, are in the long-run sure to
survive, to propagate, and to occupy the limited field, to the exclusion or
destruction of the weaker brethren. All this we pondered, and could not
much object to. In fact, we began to contract a liking for a system which at
the outset illustrates the advantages of good breeding, and which makes the
most "of every creature's best."

Could we "let by-gones be by-gones," and, beginning now, go on improving
and diversifying for the future by natural selection, could we even take up
the theory at the introduction of the actually existing species, we should
be well content; and so, perhaps, would most naturalists be. It is by no
means difficult to believe that varieties are incipient or possible
species, when we see what trouble naturalists, especially botanists, have
to distinguish between them--one regarding as a true species what another
regards as a variety; when the progress of knowledge continually increases,
rather than diminishes, the number of doubtful instances; and when there is
less agreement than ever among naturalists as to what is the basis in
Nature upon which our idea of species reposes, or how the word is to be
defined. Indeed, when we consider the endless disputes of naturalists and
ethnologists over the human races, as to whether they belong to one species
or to more, and, if to more, whether to three, or five, or fifty, we can
hardly help fancying that both may be right--or rather, that the
uni-humanitarians would have been right many thousand years ago, and the
multi-humanitarians will be several thousand years later; while at present
the safe thing to say is, that probably there is some truth on both sides.

"Natural selection," Darwin remarks, "leads to divergence of character; for
the more living beings can be supported on the same area, the more they
diverge in structure, habits, and constitution" (a principle which,
by-the-way, is paralleled and illustrated by the diversification of human
labor); and also leads to much extinction of intermediate or unimproved
forms. Now, though this divergence may "steadily tend to increase," yet
this is evidently a slow process in Nature, and liable to much counteraction
wherever man does not interpose, and so not likely to work much harm for
the future. And if natural selection, with artificial to help it, will
produce better animals and better men than the present, and fit them better
to the conditions of existence, why, let it work, say we, to the top of its
bent There is still room enough for improvement. Only let us hope that it
always works for good: if not, the divergent lines on Darwin's lithographic
diagram of "Transmutation made Easy," ominously show what small deviations
from the straight path may come to in the end.

The prospect of the future, accordingly, is on the whole pleasant and
encouraging. It is only the backward glance, the gaze up the long vista of
the past, that reveals anything alarming. Here the lines converge as they
recede into the geological ages, and point to conclusions which, upon the
theory, are inevitable, but hardly welcome. The very first step backward
makes the negro and the Hottentot our blood-relations--not that reason or
Scripture objects to that, though pride may. The next suggests a closer
association of our ancestors of the olden time with "our poor relations" of
the quadrumanous family than we like to acknowledge. Fortunately,
however--even if we must account for him scientifically --man with his two
feet stands upon a foundation of his own. Intermediate links between the
Bimana and the Quadrumana are lacking altogether; so that, put the
genealogy of the brutes upon what footing you will, the four-handed races
will not serve for our forerunners--at least, not until some monkey, live
or fossil, is producible with great-toes, instead of thumbs, upon his nether
extremities; or until some lucky geologist turns up the bones of his
ancestor and prototype in France or England, who was so busy "napping the
chuckie-stanes" and chipping out flint knives and arrow-heads in the time
of the drift, very many ages ago--before the British Channel existed, says
Lyell [III-1]--and until these men of the olden time are shown to have worn
their great-toes in the divergent and thumblike fashion. That would be
evidence indeed: but, until some testimony of the sort is produced, we must
needs believe in the separate and special creation of man, however it may
have been with the lower animals and with plants.

No doubt, the full development and symmetry of Darwin's hypothesis strongly
suggest the evolution of the human no less than the lower animal races out
of some simple primordial animal--that all are equally "lineal descendants
of some few beings which lived long before the first bed of the Silurian
system was deposited." But, as the author speaks disrespectfully of
spontaneous generation, and accepts a supernatural beginning of life on
earth, in some form or forms of being which included potentially all that
have since existed and are yet to be, he is thereby not warranted to extend
his inferences beyond the evidence or the fair probability. There seems as
great likelihood that one special origination should be followed by another
upon fitting occasion (such as the introduction of man), as that one form
should be transmuted into another upon fitting occasion, as, for instance,
in the succession of species which differ from each other only in some
details. To compare small things with great in a homely illustration: man
alters from time to time his instruments or machines, as new circumstances
or conditions may require and his wit suggest. Minor alterations and
improvements he adds to the machine he possesses; he adapts a new rig or a
new rudder to an old boat: this answers to Variation. "Like begets like,"
being the great rule in Nature, if boats could engender, the variations
would doubtless be propagated, like those of domestic cattle. In course of
time the old ones would be worn out or wrecked; the best sorts would be
chosen for each particular use, and further improved upon; and so the
primordial boat be developed into the scow, the skiff, the sloop, and other
species of water-craft--the very diversification, as well as the successive
improvements, entailing the disappearance of intermediate forms, less
adapted to any one particular purpose; wherefore these go slowly out of
use, and become extinct species: this is Natural Selection. Now, let a great
and important advance be made, like that of steam navigation: here, though
the engine might be added to the old vessel, yet the wiser and therefore
the actual way is to make a new vessel on a modified plan: this may answer
to Specific Creation. Anyhow, the one does not necessarily exclude the
other. Variation and natural selection may play their part, and so may
specific creation also. Why not?

This leads us to ask for the reasons which call for this new theory of
transmutation. The beginning of things must needs lie in obscurity, beyond
the bounds of proof, though within those of conjecture or of analogical
inference. Why not hold fast to the customary view, that all species were
directly, instead of indirectly, created after their respective kinds, as
we now behold them--and that in a manner which, passing our comprehension,
we intuitively refer to the supernatural? Why this continual striving after
"the unattained and dim?" why these anxious endeavors, especially of late
years, by naturalists and philosophers of various schools and different
tendencies, to penetrate what one of them calls "that mystery of
mysteries," the origin of species?

To this, in general, sufficient answer may be found in the activity of the
human intellect, "the delirious yet divine desire to know," stimulated as
it has been by its own success in unveiling the laws and processes of
inorganic Nature; in the fact that the principal triumphs of our age in
physical science have consisted in tracing connections where none were
known before, in reducing heterogeneous phenomena to a common cause or
origin, in a manner quite analogous to that of the reduction of supposed
independently originated species to a common ultimate origin--thus, and in
various other ways, largely and legitimately extending the domain of
secondary causes. Surely the scientific mind of an age which contemplates
the solar system as evolved from a common revolving fluid mass--which,
through experimental research, has come to regard light, heat, electricity,
magnetism, chemical affinity, and mechanical power as varieties or
derivative and convertible forms of one force, instead of independent
species--which has brought the so-called elementary kinds of matter, such
as the metals, into kindred groups, and pertinently raised the question,
whether the members of each group may not be mere varieties of one
species--and which speculates steadily in the direction of the ultimate
unity of matter, of a sort of prototype or simple element which may be to
the ordinary species of matter what the Protozoa or what the component
cells of an organism are to the higher sorts of animals and plants--the
mind of such an age cannot be expected to let the old belief about species
pass unquestioned. It will raise the question, how the diverse sorts of
plants and animals came to be as they are and where they are and will allow
that the whole inquiry transcends its powers only when all endeavors have
failed Granting the origin to be super natural or miraculous even, will not
arrest the inquiry All real origination the philosophers will say, is
supernatural, their very question is, whether we have yet gone back to the
origin and can affirm that the present forms of plants and animals are the
primordial, the miraculously created ones. And, even if they admit that,
they will still inquire into the order of the phenomena, into the form of
the miracle You might as well expect the child to grow up content with what
it is told about the advent of its infant brother Indeed, to learn that the
new comer is the gift of God, far from lulling inquiry, only stimulates
speculation as to how the precious gift was bestowed That questioning child
is father to the man--is philosopher in short-clothes.

Since, then questions about the origin of species will be raised, and have
been raised--and since the theorizings, however different in particulars,
all proceed upon the notion that one species of plant or animal is somehow
derived from another, that the different sorts which now flourish are
lineal (or unlineal) descendants of other and earlier sorts--it now
concerns us to ask, What are the grounds in Nature, the admitted facts,
which suggest hypotheses of derivation in some :shape or other? Reasons
there must be, and plausible ones, for the persistent recurrence of
theories upon this genetic basis. A study of Darwin's book, and a general
glance at the present state of the natural sciences, enable us to gather
the following as among the most suggestive and influential. We can only
enumerate them here, without much indication of their particular bearing.
There is--

1. The general fact of variability, and the general tendency of the variety
to propagate its like--the patent facts that all species vary more or less;
that domesticated plants and animals, being in conditions favorable to the
production and preservation of varieties, are apt to vary widely; and that,
by interbreeding, any variety may be fixed into a race, that is, into a
variety which comes true from seed. Many such races, it is allowed, differ
from each other in structure and appearance as widely as do many admitted
species; and it is practically very difficult, even impossible, to draw a
clear line between races and species. Witness the human races, for
instance. Wild species also vary, perhaps about as widely as those of
domestication, though in different ways. Some of them apparently vary
little, others moderately, others immoderately, to the great bewilderment
of systematic botanists and zoologists, and increasing disagreement as to
whether various forms shall be held to be original species or strong
varieties. Moreover, the degree to which the descendants of the same stock,
varying in different directions, may at length diverge, is unknown. All we
know is, that varieties are themselves variable, and that very diverse
forms have been educed from one stock.

2. Species of the same genus are not distinguished from each other by equal
amounts of difference. There is diversity in this respect analogous to that
of the varieties of a polymorphous species, some of them slight, others
extreme. And in large genera the unequal resemblance shows itself in the
clustering of the species around several types or central species, like
satellites around their respective planets. Obviously suggestive this of
the hypothesis that they were satellites, not thrown off by revolution,
like the moons of Jupiter, Saturn, and our own solitary moon, but gradually
and peacefully detached by divergent variation. That such closely-related
species may be only varieties of higher grade, earlier origin, or more
favored evolution, is not a very violent supposition. Anyhow, it was a
supposition sure to be made.

3. The actual geographical distribution of species upon the earth's surface
tends to suggest the same notion. For, as a general thing, all or most of
the species of a peculiar genus or other type are grouped in the same
country, or occupy continuous, proximate, or accessible areas. So well does
this rule hold, so general is the implication that kindred species are or
were associated geographically, that most trustworthy naturalists, quite
free from hypotheses of transmutation, are constantly inferring former
geographical continuity between parts of the world now widely disjoined, in
order to account thereby for certain generic similarities among their
inhabitants; just as philologists infer former connection of races, and a
parent language, to account for generic similarities among existing
languages. Yet no scientific explanation has been offered to account for
the geographical association of kindred species, except the hypothesis of a
common origin.

4. Here the fact of the antiquity of creation, and in particular of the
present kinds of the earth's inhabitants, or of a large part of them, comes
in to rebut the objection that there has not been time enough for any
marked diversification of living things through divergent variation--not
time enough for varieties to have diverged into what we call species.

So long as the existing species of plants and animals were thought to have
originated a few thousand years ago, and without predecessors, there was no
room for a theory of derivation of one sort from another, nor time enough
even to account for the establishment of the races which are generally
believed to have diverged from a common stock. Not so much that five or six
thousand years was a short allowance for this; but because some of our
familiar domesticated varieties of grain, of fowls, and of other animals,
were pictured and mummified by the old Egyptians more than half that number
of years ago, if not earlier. Indeed, perhaps the strongest argument for
the original plurality of human species was drawn from the identification
of some of the present races of men upon these early historical monuments
and records.

But this very extension of the current chronology, if we may rely upon the
archaeologists, removes the difficulty by opening up a longer vista. So does
the discovery in Europe of remains and implements of prehistoric races of
men, to whom the use of metals was unknown--men of the stone age, as the
Scandinavian archaeologists designate them. And now, "axes and knives of
flint, evidently wrought by human skill, are found in beds of the drift at
Amiens (also in other places, both in France and England), associated with
the bones of extinct species of animals." These implements, indeed, were
noticed twenty years ago; at a place in Suffolk they have been exhumed from
time to time for more than a century; but the full confirmation, the
recognition of the age of the deposit in which the implements occur, their
abundance, and the appreciation of their bearings upon most interesting
questions, belong to the present time. To complete the connection of these
primitive people with the fossil ages, the French geologists, we are told,
have now "found these axes in Picardy associated with remains of Elephas
primigenius, Rhinoceros tichorhinus, Equus fossilis, and an extinct species
of Bos."[III-2] In plain language, these workers in flint lived in the time
of the mammoth, of a rhinoceros now extinct, and along with horses and
cattle unlike any now existing--specifically different, as naturalists say,
from those with which man is now associated.  Their connection with
existing human races may perhaps be traced through the intervening people
of the stone age, who were succeeded by the people of the bronze age, and
these by workers in iron.[III-3] Now, various evidence carries back the
existence of many of the present lower species of animals, and probably of a
larger number of plants, to the same drift period. All agree that this was
very many thousand years ago. Agassiz tells us that the same species of
polyps which are now building coral walls around the present peninsula of
Florida actually made that peninsula, and have been building there for many
thousand centuries.

5. The overlapping of existing and extinct species, and the seemingly
gradual transition of the life of the drift period into that of the present,
may be turned to the same account. Mammoths, mastodons, and Irish elks, now
extinct, must have lived down to human, if not almost to historic times.
Perhaps the last dodo did not long outlive his huge New Zealand kindred.
The aurochs, once the companion of mammoths, still survives, but owes his
present and precarious existence to man's care. Now, nothing that we know
of forbids the hypothesis that some new species have been independently and
supernaturally created within the period which other species have survived.
Some may even believe that man was created in the days of the mammoth,
became extinct, and was recreated at a later date. But why not say the same
of the aurochs, contemporary both of the old man and of the new? Still it
is more natural, if not inevitable, to infer that, if the aurochs of that
olden time were the ancestors of the aurochs of the Lithuanian forests, so
likewise were the men of that age the ancestors of the present human races.
Then, whoever concludes that these primitive makers of rude flint axes and
knives were the ancestors of the better workmen of the succeeding stone
age, and these again of the succeeding artificers in brass and iron, will
also be likely to suppose that the Equus and Bos of that time, different
though they be, were the remote progenitors of our own horses and cattle.
In all candor we must at least concede that such considerations suggest a
genetic descent from the drift period down to the present, and allow time
enough--if time is of any account-- for variation and natural selection to
work out some appreciable results in the way of divergence into races, or
even into so-called species. Whatever might have been thought, when
geological time was supposed to be separated from the present era by a
clear line, it is now certain that a gradual replacement of old forms by
new ones is strongly suggestive of some mode of origination which may still
be operative. When species, like individuals, were found to die out one by
one, and apparently to come in one by one, a theory for what Owen
sonorously calls "the continuous operation of the ordained becoming of
living things" could not be far off.

That all such theories should take the form of a derivation of the new from
the old seems to be inevitable, perhaps from our inability to conceive of
any other line of secondary causes in this connection. Owen himself is
apparently in travail with some transmutation theory of his own conceiving,
which may yet see the light, although Darwin's came first to the birth.
Different as the two theories will probably be, they cannot fail to exhibit
that fundamental resemblance in this respect which betokens a community of
origin, a common foundation on the general facts and the obvious suggestions
of modern science. Indeed--to turn the point of a pungent simile directed
against Darwin--the difference between the Darwinian and the Owenian
hypotheses may, after all, be only that between homoeopathic and heroic
doses of the same drug.

If theories of derivation could only stop here, content with explaining the
diversification and succession of species between the teritiary period and
the present time, through natural agencies or secondary causes still in
operation, we fancy they would not be generally or violently objected to by
the savants of the present day. But it is hard, if not impossible, to find
a stopping-place. Some of the facts or accepted conclusions already
referred to, and several others, of a more general character, which must be
taken into the account, impel the theory onward with accumulated force.
Vires (not to say virus) acquirit eundo. The theory hitches on wonderfully
well to Lyell's uniformitarian theory in geology--that the thing that has
been is the thing that is and shall be--that the natural operations now
going on will account for all geological changes in a quiet and easy way,
only give them time enough, so connecting the present and the proximate
with the farthest past by almost imperceptible gradations--a view which
finds large and increasing, if not general, acceptance in physical geology,
and of which Darwin's theory is the natural complement.

So the Darwinian theory, once getting a foothold, marches; boldly on,
follows the supposed near ancestors of our present species farther and yet
farther back into the dim past, and ends with an analogical inference which
"makes the whole world kin." As we said at the beginning, this upshot
discomposes us. Several features of the theory have an uncanny look. They
may prove to be innocent: but their first aspect is suspicious, and high
authorities pronounce the whole thing to be positively mischievous. In this
dilemma we are going to take advice. Following the bent of our prejudices,
and hoping to fortify these by new and strong arguments, we are going now
to read the principal reviews which undertake to demolish the theory--with
what result our readers shall be duly informed.


II


"I can entertain no doubt, after the most deliberate study and
dispassionate judgment of which I am capable, that the view which most
naturalists entertain, and which I formerly entertained, namely, that each
species has been independently created, is erroneous. I am fully convinced
that species are not immutable; but that those belonging to what are called
the same genera are lineal descendants of some other and generally extinct
species, in the same manner as the acknowledged varieties of any one species
are the descendants of that species. Furthermore, I am convinced that
Natural Selection has been the main, but not exclusive, means of
modification."


This is the kernel of the new theory, the Darwinian creed, as recited at
the close of the introduction to the remarkable book under consideration.
The questions, "What will he do with it?" and "How far will he carry it?"
the author answers at the close of the volume:


"I cannot doubt that the theory of descent with modification embraces all
the members of the same class." Furthermore, "I believe that all animals
have descended from at most only four or five progenitors, and plants from
an equal or lesser number."


Seeing that analogy as strongly suggests a further step in the same
direction, while he protests that "analogy may be a deceitful guide," yet
he follows its inexorable leading to the inference that--

"Probably all the organic beings which have ever lived on this ear have
descended from some one primordial form, into which life was first
breathed."[III-4]


In the first extract we have the thin end of the wedge driven a little way;
in the last, the wedge driven home.

We have already sketched some of the reasons suggestive of such a theory of
derivation of species, reasons which gave it plausibility, and even no small
probability, as applied to our actual world and to changes occurring since
the latest tertiary period. We are well pleased at this moment to find that
the conclusions we were arriving at in this respect are sustained by the
very high authority and impartial judgment of Pictet, the Swiss
paleontologist. In his review of Darwin's book[III-5] -- the fairest and
most admirable opposing one that has appeared--he freely accepts that
ensemble of natural operations which Darwin impersonates under the now
familiar name of Natural Selection, allows that the exposition throughout
the first chapters seems "a la fois prudent et fort," and is disposed to
accept the whole argument in its foundations, that is, so far as it relates
to what is now going on, or has taken place in the present geological
period--which period he carries back through the diluvial epoch to the
borders of the tertiary.[III-6] Pictet accordingly admits that the theory
will very well account for the origination by divergence of nearly-related
species, whether within the present period or in remoter geological times;
a very natural view for him to take, since he appears to have reached and
published, several years ago, the pregnant conclusion that there most
probably was some material connection between the closely-related species of
two successive faunas, and that the numerous close species, whose limits are
so difficult to determine, were not all created distinct and independent.
But while thus accepting, or ready to accept, the basis of Darwin's theory,
and all its legitimate direct inferences, he rejects the ultimate
conclusions, brings some weighty arguments to bear against them, and is
evidently convinced that he can draw a clear line between the sound
inferences, which he favors, and the unsound or unwarranted theoretical
deductions, which he rejects. We hope he can.

This raises the question, Why does Darwin press his theory to these extreme
conclusions? Why do all hypotheses of derivation converge so inevitably to
one ultimate point? Having already considered some of the reasons which
suggest or support the theory at its outset--which may carry it as far as
such sound and experienced naturalists as Pictet allow that it may be
true--perhaps as far as Darwin himself unfolds it in the introductory
proposition cited at the beginning of this article--we may now inquire after
the motives which impel the theorist so much farther. Here proofs, in the
proper sense of the word, are not to be had. We are beyond the region of
demonstration, and have only probabilities to consider. What are these
probabilities? What work will this hypothesis do to establish a claim to be
adopted in its completeness? Why should a theory which may plausibly enough
account for the diversification of the species of each special type or
genus be expanded into a general system for the origination or successive
diversification of all species, and all special types or forms, from four
or five remote primordial forms, or perhaps from one? We accept the theory
of gravitation because it explains all the facts we know, and bears all the
tests that we can put it to. We incline to accept the nebular hypothesis,
for similar reasons; not because it is proved--thus far it is incapable of
proof--but because it is a natural theoretical deduction from accepted
physical laws, is thoroughly congruous with the facts, and because its
assumption serves to connect and harmonize these into one probable and
consistent whole. Can the derivative hypothesis be maintained and carried
out into a system on similar grounds? If so, however unproved, it would
appear to be a tenable hypothesis, which is all that its author ought now
to claim. Such hypotheses as, from the conditions of the case, can neither
be proved nor disproved by direct evidence or experiment, are to be tested
only indirectly, and therefore imperfectly, by trying their power to
harmonize the known facts, and to account for what is otherwise
unaccountable. So the question comes to this: What will an hypothesis of
the derivation of species explain which the opposing view leaves
unexplained?

Questions these which ought to be entertained before we take up the
arguments which have been advanced against this theory. We can barely
glance at some of the considerations which Darwin adduces, or will be sure
to adduce in the future and fuller exposition which is promised. To display
them in such wise as to indoctrinate the unscientific reader would require
a volume. Merely to refer to them in the most general terms would suffice
for those familiar with scientific matters, but would scarcely enlighten
those who are not. Wherefore let these trust the impartial Pictet, who
freely admits that, "in the absence of sufficient direct proofs to justify
the possibility of his hypothesis, Mr. Darwin relies upon indirect proofs,
the bearing of which is real and incontestable;" who concedes that "his
theory accords very well with the great facts of comparative anatomy and
zoology--comes in admirably to explain unity of composition of organisms,
also to explain rudimentary and representative organs, and the natural
series of genera and species--equally corresponds with many paleontological
data--agrees well with the specific resemblances which exist between two
successive faunas, with the parallelism which is sometimes observed between
the series of paleontological succession and of embryonal development,"
etc.; and finally, although he does not accept the theory in these results,
he allows that "it appears to offer the best means of explaining the manner
in which organized beings were produced in epochs anterior to our own."

What more than this could be said for such an hypothesis? Here, probably,
is its charm, and its strong hold upon the speculative mind. Unproven
though it be, and cumbered prima facie with cumulative improbabilities as
it proceeds, yet it singularly accords with great classes of facts
otherwise insulated and enigmatic, and explains many things which are thus
far utterly inexplicable upon any other scientific assumption.

We have said that Darwin's hypothesis is the natural complement to Lyell's
uniformitarian theory in physical geology. It is for the organic world what
that is for the inorganic; and the accepters of the latter stand in a
position from which to regard the former in the most favorable light.
Wherefore the rumor that the cautious Lyell himself has adopted the
Darwinian hypothesis need not surprise us. The two views are made for each
other, and, like the two counterpart pictures for the stereoscope, when
brought together, combine into one apparently solid whole.

If we allow, with Pictet, that Darwin's theory will very well serve for all
that concerns the present epoch of the world's history--an epoch in which
this renowned paleontologist includes the diluvial or quaternary
period--then Darwin's first and foremost need in his onward course is a
practicable road from this into and through the tertiary period, the
intervening region between the comparatively near and the far remote past.
Here Lyell's doctrine paves the way, by showing that in the physical geology
there is no general or absolute break between the two, probably no greater
between the latest tertiary and the quaternary period than between the
latter and the present time. So far, the Lyellian view is, we suppose,
generally concurred in. It is largely admitted that numerous tertiary
species have continued down into the quaternary, and many of them to the
present time. A goodly percentage of the earlier and nearly half of the
later tertiary mollusca, according to Des Hayes, Lye!!, and, if we mistake
not, Bronn, still live. This identification, however, is now questioned by
a naturalist of the very highest authority. But, in its bearings on the new
theory, the point here turns not upon absolute identity so much as upon
close resemblance. For those who, with Agassiz, doubt the specific identity
in any of these cases, and those who say, with Pictet, that "the later
tertiary deposits contain in general the debris of species very nearly
related to those which still exist, belonging to the same genera, but
specifically different," may also agree with Pictet, that the
nearly-related species of successive faunas must or may have had "a
material connection." But the only material connection that we have an idea
of in such a case is a genealogical one. And the supposition of a
genealogical connection is surely not unnatural in such cases--is
demonstrably the natural one as respects all those tertiary species which
experienced naturalists have pronounced to be identical with existing ones,
but which others now deem distinct For to identify the two is the same
thing as to conclude the one to be the ancestor of the other No doubt there
are differences between the tertiary and the present individuals,
differences equally noticed by both classes of naturalists, but differently
estimated By the one these are deemed quite compatible, by the other
incompatible, with community of origin But who can tell us what amount of
difference is compatible with community of origin? This is the very
question at issue, and one to be settled by observation alone Who would have
thought that the peach and the nectarine came from one stock? But, this
being proved is it now very improbable that both were derived from the
almond, or from some common amygdaline progenitor? Who would have thought
that the cabbage, cauliflower, broccoli kale, and kohlrabi are derivatives
of one species, and rape or colza, turnip, and probably ruta-baga, of
another species? And who that is convinced of this can long undoubtingly
hold the original distinctness of turnips from cabbages as an article of
faith? On scientific grounds may not a primordial cabbage or rape be
assumed as the ancestor of all the cabbage races, on much the same ground
that we assume a common ancestry for the diversified human races? If all
Our breeds of cattle came from one stock why not this stock  from the
auroch, which has had all the time between the diluvial and the historic
periods in which to set off a variation perhaps no greater than the
difference between some sorts of domestic cattle?

That considerable differences are often discernible between tertiary
individuals and their supposed descendants of the present day affords no
argument against Darwin's theory, as has been rashly thought, but is
decidedly in its favor. If the identification were so perfect that no more
differences were observable between the tertiary and the recent shells than
between various individuals of either, then Darwin's opponents, who argue
the immutability of species from the ibises and cats preserved by the
ancient Egyptians being just like those of the present day, could
triumphantly add a few hundred thousand years more to the length of the
experiment and to the force of their argument.

As the facts stand, it appears that, while some tertiary forms are
essentially undistinguishable from existing ones, others are the same with
a difference, which is judged not to be specific or aboriginal; and yet
others show somewhat greater differences, such as are scientifically
expressed by calling them marked varieties, or else doubtful species; while
others, differing a little more, are confidently termed distinct, but
nearly-related species. Now, is not all this a question of degree, of mere
gradation of difference? And is it at all likely that these several
gradations came to be established in two totally different ways--some of
them (though naturalists can't agree which) through natural variation, or
other secondary cause, and some by original creation, without secondary
cause? We have seen that the judicious Pictet answers such questions as
Darwin would have him do, in affirming that, in all probability, the
nearly-related species of two successive faunas were materially connected,
and that contemporaneous species, similarly resembling each other, were not
all created so, but have become so. This is equivalent to saying that
species (using the term as all naturalists do, and must continue to employ
the word) have only a relative, not an absolute fixity; that differences
fully equivalent to what are held to be specific may arise in the course of
time, so that one species may at length be naturally replaced by another
species a good deal like it, or may be diversified into two, three, or more
species, or forms as different as species. This concedes all that Darwin has
a right to ask, all that he can directly infer from evidence. We must add
that it affords a locus standi, more or less tenable, for inferring more.

Here another geological consideration comes in to help on this inference.
The species of the later tertiary period for the most part not only
resembled those of our days--many of them so closely as to suggest an
absolute continuity--but also occupied in general the same regions that
their relatives occupy now. The same may be said, though less specially, of
the earlier tertiary and of the later secondary; but there is less and less
localization of forms as we recede, yet some localization even in palaeozoic
times. While in the secondary period one is struck with the similarity of
forms and the identity of many of the species which flourished apparently
at the same time in all or in the most widely-separated parts of the world,
in the tertiary epoch, on the contrary, along with the increasing
specialization of climates and their approximation to the present state, we
find abundant evidence of increasing localization of orders, genera and
species, and this localization strikingly accords with the present
geographical distribution of the same groups of species Where the imputed
forefathers lived their relatives and supposed descendants now flourish All
the actual classes of the animal and vegetable kingdoms were represented in
the tertiary faunas and floras and in nearly the same proportions and the
same diversities as at present The faunas of what is now Europe, Asia
America and Australia, differed from each other much as they now differ: in
fact--according to Adolphe Brongniart, whose statements we here
condense[III-7]--the inhabitants of these different regions appear for the
most part to have acquired, before the close of the tertiary period, the
characters which essentially distinguish their existing faunas. The Eastern
Continent had then, as now, its great pachyderms, elephants, rhinoceros,
hippopotamus; South America, its armadillos, sloths, and anteaters;
Australia, a crowd of marsupials; and the very strange birds of New Zealand
had predecessors of similar strangeness.

Everywhere the same geographical distribution as now, with a difference in
the particular area, as respects the northern portion of the continents,
answering to a warmer climate then than ours, such as allowed species of
hippopotamus, rhinoceros, and elephant, to range even to the regions now
inhabited by the reindeer and the musk-ox, and with the serious disturbing
intervention of the glacial period within a comparatively recent time. Let
it be noted also that those tertiary species which have continued with
little change down to our days are the marine animals of the lower grades,
especially mollusca. Their low organization, moderate sensibility, and the
simple conditions of an existence in a medium like the ocean, not subject
to great variation and incapable of sudden change, may well account for
their continuance; while, on the other hand, the more intense, however
gradual, climatic vicissitudes on land, which have driven all tropical and
subtropical forms out of the higher latitudes and assigned to them their
actual limits, would be almost sure to extinguish such huge and unwieldy
animals as mastodons, mammoths, and the like, whose power of enduring
altered circumstances must have been small.

This general replacement of the tertiary species of a country by others so
much like them is a noteworthy fact. The hypothesis of the independent
creation of all species, irrespective of their antecedents, leaves this
fact just as mysterious as is creation itself; that of derivation
undertakes to account for it. Whether it satisfactorily does so or not, it
must be allowed that the facts well accord with that hypothesis. The same
may be said of another conclusion, namely, that the geological succession
of animals and plants appears to correspond in a general way with their
relative standing or rank in a natural system of classification. It seems
clear that, though no one of the grand types of the animal kingdom can be
traced back farther than the rest, yet the lower classes long preceded the
higher; that there has been on the whole a steady progression within each
class and order; and that the highest plants and animals have appeared only
in relatively modern times. It is only, however, in a broad sense that this
generalization is now thought to hold good. It encounters many apparent
exceptions, and sundry real ones. So far as the rule holds, all is as it
should be upon an hypothesis of derivation.

The rule has its exceptions. But, curiously enough, the most striking class
of exceptions, if such they be, seems to us even more favorable to the
doctrine of derivation than is the general rule of a pure and simple
ascending gradation. We refer to what Agassiz calls prophetic and synthetic
types; for which the former name may suffice, as the difference between the
two is evanescent.


"It has been noticed," writes our great zoologist, "that certain types,
which are frequently prominent among the representatives of past ages,
combine in their structure peculiarities which at later periods are only
observed separately in different, distinct types. Sauroid fishes before
reptiles, Pterodactyles before birds, Ichthyosauri before dolphins, etc.
There are entire families, of nearly every class of animals, which in the
state of their perfect development exemplify such prophetic relations.

The sauroid fishes of the past geological ages are an example of this kind
These fishes which preceded the appearance of reptiles present a
combination of ichthyic and reptilian characters not to be found in the
true members of this class, which form its bulk at present. The
Pterodactyles, which preceded the class of birds, and the Ichthyosauri,
which preceded the Cetacea, are other examples of such prophetic
types."--(Agassiz, "Contributions, Essay on Classification," p. 117.)


Now, these reptile-like fishes, of which gar-pikes are the living
representatives, though of earlier appearance, are admittedly of higher rank
than common fishes. They dominated until reptiles appeared, when they
mostly gave place to (or, as the derivationists will insist, were resolved
by divergent variation and natural selection into) common fishes, destitute
of reptilian characters, and saurian reptiles--the intermediate grades,
which, according to a familiar piscine saying, are "neither fish, flesh,
nor good red-herring," being eliminated and extinguished by natural
consequence of the struggle for existence which Darwin so aptly portrays.
And so, perhaps, of the other prophetic types. Here type and antitype
correspond. If these are true prophecies, we need not wonder that some who
read them in Agassiz's book will read their fulfillment in Darwin's.

Note also, in this connection, that along with a wonderful persistence of
type, with change of species, genera, orders, etc., from formation to
formation, no species and no higher group which has once unequivocally died
out ever afterward reappears. Why is this, but that the link of generation
has been sundered? Why, on the hypothesis of independent originations, were
not failing species recreated, either identically or with a difference, in
regions eminently adapted to their well-being? To take a striking case.
That no part of the world now offers more suitable conditions for wild
horses and cattle than the pampas and other plains of South America, is
shown by the facility with which they have there run wild and enormously
multiplied, since introduced from the Old World not long ago. There was no
wild American stock. Yet in the times of the mastodon and megatherium, at
the dawn of the present period, wild-horses--certainly very much like the
existing horse--roamed over those plains in abundance. On the principle of
original and direct created adaptation of species to climate and other
conditions, why were they not reproduced, when, after the colder
intervening era, those regions became again eminently adapted to such
animals? Why, but because, by their complete extinction in South America,
the line of descent was there utterly broken? Upon the ordinary hypothesis,
there is no scientific explanation possible of this series of facts, and of
many others like them. Upon the new hypothesis, "the succession of the same
types of structure within the same areas during the later geological
periods ceases to be mysterious, and is simply explained by inheritance."
Their cessation is failure of issue.

Along with these considerations the fact (alluded to on page 98) should be
remembered that, as a general thing, related species of the present age are
geographically associated. The larger part of the plants, and still more of
the animals, of each separate country are peculiar to it; and, as most
species now flourish over the graves of their by-gone relatives of former
ages, so they now dwell among or accessibly near their kindred species.

Here also comes in that general "parallelism between the order of
succession of animals and plants in geological times, and the gradation
among their living representatives" from low to highly organized, from
simple and general to complex and specialized forms; also "the parallelism
between the order of succession of animals in geological times and the
changes their living representatives undergo during their embryological
growth," as if the world were one prolonged gestation. Modern science has
much insisted on this parallelism, and to a certain extent is allowed to
have made it out. All these things, which conspire to prove that the
ancient and the recent forms of life "are somehow intimately connected
together in one grand system," equally conspire to suggest that the
connection is one similar or analogous to generation. Surely no naturalist
can be blamed for entering somewhat confidently upon a field of speculative
inquiry which here opens so invitingly; nor need former premature endeavors
and failures utterly dishearten him.

All these things, it may naturally be said, go to explain the order, not
the mode, of the incoming of species. But they all do tend to bring out the
generalization expressed by Mr. Wallace in the formula that "every species
has come into existence coincident both in time and space with preexisting
closely-allied species." Not, however, that this is proved even of existing
species as a matter of general fact. It is obviously impossible to prove
anything of the kind. But we must concede that the known facts strongly
suggest such an inference. And--since species are only congeries of
individuals, since every individual came into existence in consequence of
preexisting individuals of the same sort, so leading up to the individuals
with which the species began, and since the only material sequence we know
of among plants and animals is that from parent to progeny--the presumption
becomes exceedingly strong that the connection of the incoming with the
preexisting species is a genealogical one.

Here, however, all depends upon the probability that Mr. Wallace's
inference is really true. Certainly it is not yet generally accepted; but a
strong current is setting toward its acceptance.

So long as universal cataclysms were in vogue, and all life upon the earth
was thought to have been suddenly destroyed and renewed many times in
succession, such a view could not be thought of. So the equivalent view
maintained by Agassiz, and formerly, we believe, by D'Orbigny, that
irrespectively of general and sudden catastrophes, or any known adequate
physical cause, there has been a total depopulation at the close of each
geological period or formation, say forty or fifty times or more, followed
by as many independent great acts of creation, at which alone have species
been originated, and at each of which a vegetable and an animal kingdom
were produced entire and complete, full-fledged, as flourishing, as
wide-spread, and populous, as varied and mutually adapted from the
beginning as ever afterward--such a view, of course, supersedes all
material connection between successive species, and removes even the
association and geographical range of species entirely out of the domain of
physical causes and of natural science. This is the extreme opposite of
Wallace's and Darwin's view, and is quite as hypothetical. The nearly
universal opinion, if we rightly gather it, manifestly is, that the
replacement of the species of successive formations was not complete and
simultaneous, but partial and successive; and that along the course of each
epoch some species probably were introduced, and some, doubtless, became
extinct. If all since the tertiary belongs to our present epoch, this is
certainly true of it: if to two or more epochs, then the hypothesis of a
total change is not true of them.

Geology makes huge demands upon time; and we regret to find that it has
exhausted ours--that what we meant for the briefest and most general sketch
of some geological considerations in favor of Darwin's hypothesis has so
extended as to leave no room for considering "the great facts of
comparative anatomy and zoology" with which Darwin's theory "very well
accords," nor for indicating how "it admirably serves for explaining the
unity of composition of all organisms, the existence of representative and
rudimentary organs, and the natural series which genera and species
compose." Suffice it to say that these are the real strongholds of the new
system on its theoretical side; that it goes far toward explaining both the
physiological and the structural gradations and relations between the two
kingdoms, and the arrangement of all their   forms in groups subordinate to
groups, all within a few great types; that it reads the riddle of abortive
organs and of morphological conformity, of which no other theory has ever
offered a scientific explanation, and supplies a ground for harmonizing the
two fundamental ideas which naturalists and philosophers conceive to have
ruled the orga

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