The Theories of Darwin and Their Relation to Philosophy, Religion, and Morality
by Rudolf Schmid · English · Gutenberg #22150 · 691,354 chars · public domain (US)
The Project Gutenberg eBook of The Theories of Darwin and Their Relation to Philosophy, Religion, and Morality
This eBook is for the use of anyone anywhere in the United States and
most other parts of the world at no cost and with almost no restrictions
whatsoever. You may copy it, give it away or re-use it under the terms
of the Project Gutenberg License included with this eBook or online
at www.gutenberg.org. If you are not located in the United States,
you will have to check the laws of the country where you are located
before using this eBook.
Title: The Theories of Darwin and Their Relation to Philosophy, Religion, and Morality
Author: Rudolf Schmid
Translator: G. A. Zimmermann
Release date: July 26, 2007 [eBook #22150]
Most recently updated: January 2, 2021
Language: English
Other information and formats: www.gutenberg.org/ebooks/22150
Credits: Produced by Marilynda Fraser-Cunliffe, Keith Edkins and
the Online Distributed Proofreading Team at
https://www.pgdp.net (This file was made using scans of
public domain works from the University of Michigan Digital
Libraries.)
*** START OF THE PROJECT GUTENBERG EBOOK THE THEORIES OF DARWIN AND THEIR RELATION TO PHILOSOPHY, RELIGION, AND MORALITY ***
Produced by Marilynda Fraser-Cunliffe, Keith Edkins and
the Online Distributed Proofreading Team at
https://www.pgdp.net (This file was made using scans of
public domain works from the University of Michigan Digital
Libraries.)
Transcriber's note: A few typographical errors have been corrected: they
are listed at the end of the text.
THE THEORIES OF DARWIN.
HALL, STUTTGART, April 5, 1880.
We hereby authorize the Rev. Dr. G. A. Zimmermann to translate into English
the book entitled
_Die Darwin'schen Theorien und ihre Stellung zur Philosophie, Religion und
Moral von Rudolf Schmid_.
We declare that we know of no other translation of the said book and that
Dr. Zimmermann's translation will be the only one authorized by us for the
United States as well as for the British Empire and its Dominions.
(_The Author_) RUDOLF SCHMID.
(_The Publisher_) PAUL MOSER.
* * * * *
THE
THEORIES OF DARWIN
AND THEIR RELATION TO
PHILOSOPHY, RELIGION AND MORALITY.
By RUDOLF SCHMID, President of the Theological Seminary at Schönthal,
Würtemberg.
TRANSLATED FROM THE GERMAN BY G. A. ZIMMERMANN, PH.D.
WITH AN INTRODUCTION BY THE DUKE OF ARGYLL
CHICAGO:
JANSEN McCLURG. & COMPANY
1883.
* * * * *
COPYRIGHT
BY JANSEN, MCCLURG & CO.
A.D. 1882.
R. R. DONNELLEY & SONS, PRINTERS.
* * * * * {1}
AUTHOR'S PREFACE
* * * * *
The movement which received its impulse as well as its name from Darwin,
seems to have recently passed its distinctest phase; but the more prominent
points of opposition, religious, ethical, and scientific, which have been
revealed through it, remain as sharply contrasted as before. The author of
this book desires, in the first place, to be of service to such readers as
feel the need of setting themselves right upon these questions, which touch
the highest interests of mankind, but who lack time and opportunity to
investigate independently a realm in which so many and so heterogeneous
sciences come into mutual contact. The illogical and confused manner in
which some noisy leaders confound these sciences and their problems and
consequences, renders it still more difficult to arrive at a satisfactory
result; and thus perhaps many readers will look with interest upon an
investigation designed to simplify the different problems and the different
attempts at their solution, and to treat them not only in their relations
to each other, but also separately. But with this primary object, the
author combines another: to render a service to some among the many who
perceive the harmony between their scientific conviction and their
religious need threatened or shaken by the results of science, and who are
unwilling to lose this harmony, or, having lost it, desire to regain it.
Those voices are indeed becoming louder, and more generally and willingly
heard, which proclaim an irreconcilability between faith and {2} knowledge,
between the religious and the scientific views of the world; which declare
that peace between the two can only be had at the price either of
permitting the religious impulses of the heart to be stifled in favor of
science, of satisfying the religious need of the mind with a nourishment
which in the light of science proves to be an illusion, or, as sceptics in
theory and eclectics in practice, of renouncing with resignation a logical
connection and foundation to their former view of the world. The most
striking proof of the extent to which these voices are heard, is the fact
that it has been possible for a one-sided pessimism to become the
fashionable system of philosophy in a Christian nation. The most effective
means for opposing such discordant voices, and for making amends for the
disagreements which they have occasioned, undoubtedly consists in the
actual proof of the contrary of their theories, in the clear presentation
of a standpoint from which not only the most unrestricted freedom of
investigation and the most unreserved acknowledgment of its results shall
be in perfect harmony with the undiminished care of our entire religious
possession, but in which this peace is preserved and forever established by
the very fact that one function of the mind directly requires the other,
one possession directly guarantees the other. This is the standpoint of the
author, and from it he has endeavored to treat all the questions which are
to be taken into consideration. Should he, by his exposition of this
standpoint, succeed in helping even a few readers in reaching the
conviction of the actual harmony between the scientific, religious, and
ethical acquisitions of mankind, or in confirming them anew in such
conviction, he would find himself amply rewarded for this first extended
venture before the public.
R. S.
{3}
AUTHOR'S PREFACE TO AMERICAN EDITION.
Six years have elapsed since I wrote the book which is now going forth in
English dress. The great leader of the theories in question has passed
away; the waves of thought he set in motion are assuming smoother shape;
and I can only add to what I have already written, that not only have I had
no occasion to retract any of the statements or views laid down in the
book, but I perceive the religious as well as the scientific world growing
more and more into accord with the views I have maintained, and which were
at first so vehemently opposed.
I owe so much to the literary men of the English tongue on both sides of
the Atlantic, that I shall be glad if, through the devoted labors of the
translator, I am enabled to pay them a tribute of gratitude by aiding them
in clearing the way for thought in these much disputed fields, or in
reconciling in their minds the conflict between faith and science.
R. S.
SCHÖNTHAL, WÜRTEMBERG, _September_, 1882.
* * * * *
{5}
INTRODUCTION TO AMERICAN EDITION,
BY THE DUKE OF ARGYLL.
* * * * *
It is well known that Mr. Darwin's theory on the Origin of Species has been
accepted in Germany more widely, with more absolute faith, and with more
vehement enthusiasm, than in the country of its birth. In Germany, more
conspicuously than elsewhere, it has itself become the subject of
developments as strange and as aberrant as any which it assumes in the
history of Organic Life. The most extravagant conclusions have been drawn
from it--invading every branch of human thought, in Science, in Philosophy,
and in Religion. These conclusions have been preached, too, with a
dogmatism as angry and as intolerant as any of the old theologies. It is
the fate of every idea which is new and fruitful, that it is ridden to the
death by excited novices. We can not be surprised if this fate has
overtaken the idea that all existing animal forms have had their ancestry
in other forms which exist no longer, and have been derived from these by
ordinary generation through countless stages of descent. Although this is
an idea which, whether true or not, is entirely subordinate to the larger
idea of creation, it usurps in many minds the character of a substitute.
This is natural enough. The theory, or at least the language, of
Evolutionists, puts forward a visible order of phenomena as a complete and
all-sufficient account of its own origin and cause. However unsatisfactory
this may be to the higher faculties of the mind, it is eminently {6}
satisfactory to those other faculties which are lower in the scale. It
dismisses as needless, or it postpones indefinitely, all thought of the
agencies which are ultimate and unseen. Just as in the physical world, some
trivial object which is very near us may shut out the whole of a wide
horizon, so in the intellectual world, some coarse mechanical conception
may shut out all the kingdom of Nature and the glory of it.
Two great subjects of investigation lie before us. The first is to
ascertain how far the Theory of Evolution represents an universal fact, or
only one very partial and fragmentary aspect of a great variety of facts
connected with the origin and development of Organic Life. The second and
by far the most important inquiry, is to estimate aright, or as nearly as
we can, the relative place and importance of these facts in the Philosophy
of Nature.
Subjects of investigation so rich and manifold as these may well attract
all the most varied gifts of the human mind. This they have already done,
and there is every indication that they will continue to do so for
generations yet to be. Already an immense literature is devoted to them;
and every fresh effort of observation and of reasoning seems to open out
new and fruitful avenues of thought. The work which is here introduced to
the English reader contains an excellent review of this literature, so far
as it is represented in the English and German languages. Knowing the
author personally, as I have done for many years, I recognize with pleasure
in his work all the carefulness of inquiry, and all the conscientiousness
of reasoning, which belong to a singularly candid and patient mind.
ARGYLL.
INVERARY CASTLE, SCOTLAND,
_September, 1882._
* * * * *
{7}
NOTE BY THE TRANSLATOR.
The consideration which this work has received from the leaders of
religious and philosophic thought in Germany, and, indeed, wherever it has
been read in its original form, has led the translator to believe that an
English version of it would be acceptable. Especially in America, where
religious problems and religious thought are so intimately connected with
the processes of scientific and philosophic investigation, and where the
agitation of these problems is so peculiarly active and violent, it has
seemed that a work marked by so much scholarship, profundity, and
comprehensiveness and originality of treatment, must serve an important
purpose to the cause of religious no less than of scientific truth. It may
be explained here, that the author resided for some years in the family of
the Duke of Argyll, and there breathed, to a certain extent, the scientific
air of Darwinism in its very origin; and thus his familiarity with all the
results of modern scientific research, added to his theological and
philosophical acquirements, enable him, with a most admirable blending of
the spirit of fairness and toleration with logical severity of treatment,
to bring these different domains into their proper relation with each other
and to establish between them that essential harmony in which consists the
solution of these most profound and vital problems of man's welfare.
Of the translation it may properly be said that, while the aim has been to
give the work the clearest possible form consistent with that strict
fidelity to the original which is {8} especially demanded by the character
of its material, the translator has not hoped to make the work altogether
"easy" reading. Peculiarities of the author's style have been, it is
believed, largely preserved; and occasional difficulties of apprehension
are no doubt to be expected, both from the method of treatment and from the
profound and abstruse character of the topics treated. The translator will
be well satisfied if it shall be found that he has succeeded in performing
his task without adding unduly to the seeming obscurities of certain
passages--obscurities which, however, will no doubt vanish before that
degree of mental application without which such works may not be read at
all intelligibly.
Acknowledgments are properly due and are gladly rendered to George C.
Dawson, Esq., of Chicago, and to Mr. Francis F. Browne, editor of _The
Dial_, for valuable assistance in revising and perfecting this version.
G. A. Z.
CHICAGO, _October_, 1882.
* * * * *
{9}
CONTENTS.
INTRODUCTION ... 17
_PART FIRST:_
_THE DARWINIAN THEORIES_.
BOOK I.
THE PURELY SCIENTIFIC THEORIES.
The Scientific Problem, ... 23
CHAPTER I.
RISE OF THE DARWINIAN THEORIES.
§1. Direct Predecessors, ... 30
§2. Indirect Preparations, ... 33
CHAPTER II.
HISTORY OF THE DARWINIAN THEORIES.
§1. Darwin, ... 38
§2. The Followers of Darwin.--Ernst Häckel, ... 45
§3. Modifications of the Theory.--Moriz Wagner. Wigand, ... 52
CHAPTER III.
PRESENT STATE OF THE DARWINIAN THEORIES.
§1. The Theory of Descent, ... 61
§2. The Theory of Evolution.--Archæology, Ethnography, Philology, ... 77
§3. The Theory of Selection, ... 100
{10}
BOOK II.
THE PHILOSOPHIC COMPLETIONS AND CONSEQUENCES
OF THE DARWINIAN THEORIES.
The Philosophic Problems, ... 108
CHAPTER I.
THE NATURO-PHILOSOPHIC SUPPLEMENTS OF THE DARWINIAN THEORIES.
§1. The Origin of Self-Consciousness and of Free Moral
Self-Determination, ... 115
§2. The Origin of Sensation and of Consciousness, ... 127
§3. The Origin of Life, ... 132
§4. The Elements of the World; the Theory of Atoms, and the Mechanical
View of the World, ... 140
CHAPTER II.
METAPHYSICAL CONCLUSIONS DRAWN FROM THE DARWINIAN THEORIES.
§1. Elimination of the Idea of Design in the World.--Monism, ... 158
{11}
_PART SECOND:_
_THE POSITION OF THE DARWINIAN THEORIES
IN REFERENCE TO RELIGION AND MORALITY._
BOOK I.
HISTORICAL AND CRITICAL.
Plan of Treatment, ... 185
_A. THE DARWINIAN THEORIES AND RELIGION._
CHAPTER I.
MORE OR LESS NEGATIVE POSITION IN REFERENCE TO RELIGION.
§1. Extreme Negation: L. Büchner and Consistent Materialism, ... 188
§2. Replacement of Religion Through a Religious Worship of the
Universe.--Strauss. Oskar Schmidt. Häckel, ... 190
§3. Pious Renunciation of the Knowability of God. Wilhelm Bleek. Albert
Lange. Herbert Spencer, ... 193
§4. Spinoza and Hegel in the Garb of Darwin.--Carneri, Ed. von Hartmann,
... 203
§5. Reëcho of Negation on the Side of the Christian View of the World,
... 206
CHAPTER II.
REFORM OF RELIGION, OR AT LEAST OF THE SCIENCE OF RELIGION, THROUGH
DARWINISM.
§1. Heinrich Lang. Friedrich Vischer. Gustav Jäger, ... 210
CHAPTER III.
PEACE BETWEEN RELIGION AND DARWINISM.
§1. Darwin. Wallace. Owen. Asa Gray. Mivart. McCosh. Anderson. K. E. von
Baer. Alexander Braun. Braubach, and others, ... 217
{12}
_B. THE DARWINIAN THEORIES AND MORALITY_.
Preliminary View, ... 228
CHAPTER IV.
ANTAGONISM BETWEEN DARWINISM AND MORALITY.
§1. Objections to Darwinism from an Ethical Standpoint, ... 230
CHAPTER V.
REFORM OF MORALITY THROUGH DARWINISM.
§1. The Materialists and Monists. Darwin and the English Utilitarians.
Gustav Jäger, ... 233
CHAPTER VI.
NEUTRALITY AND PEACE BETWEEN DARWINISM AND MORALITY.
§1. Mivart. Alexander Braun, and others, ... 245
BOOK II.
ANALYTICAL.
Preliminary View, ... 249
_A. THE DARWINIAN THEORIES AND RELIGION_.
CHAPTER I.
THE DARWINIAN THEORIES AND THE THEISTIC VIEW OF THE WORLD.
_a. The Position of Purely Scientific Darwinism in Reference to Theism_.
§1. Scientific Investigation and Theism.--The Idea of Creation, ... 252
{13}
§2. The Descent Theory and Theism, ... 259
§3. The Evolution Theory and Theism, ... 263
§4. The Selection Theory and Theism, ... 270
_b. The Darwinistic Philosophies in their Position Regarding Theism_.
§5. The Naturo-Philosophic Supplements of Darwinism and Theism, ... 273
§6. Elimination of the Idea of Design, or its Acknowledgment and Theism,
... 284
CHAPTER II.
THE DARWINIAN THEORIES AND POSITIVE CHRISTIANITY.
§1. The Creation of the World, ... 290
§2. The Creation of Man, ... 314
§3. The Primitive Condition of Man.--Paradise, the Fall of Man, and
Primitive History, ... 321
§4. Providence, Hearing of Prayer, and Miracles, ... 345
§5. The Redeemer and the Redemption, the Kingdom of God, and the
Receiving of Salvation, ... 373
§6. Eschatology, ... 375
_B. THE DARWINIAN THEORIES AND MORALITY_.
CHAPTER III.
DARWINISM AND MORAL PRINCIPLES.
§1. Darwinistic Naturalism and Moral Principles, ... 379
§2. Scientific Darwinism and Moral Principles, ... 386
CHAPTER IV.
DARWINISM AND MORAL LIFE.
§1. Darwinistic Naturalism and Moral Life, ... 391
§2. Scientific Naturalism and Moral Life, ... 396
CONCLUSION, ... 399
* * * * *
{14}
AUTHORS CITED.
* * * * *
Agassiz, Louis, 35, 37, 50, 320.
Anderson, 225.
Anonymus, "the Unconscious," etc., 128, 129, 131, 134, 159.
Anonymus, "Vestiges," etc., 33.
Argyll, Duke of, 50, 91, 92, 135, 172, 202, 288.
Ausland, 159, 240, 281.
Baer, Karl Ernst von, 36, 54, 56, 71, 74, 81, 83, 106, 132, 149, 160,
177, 226, 259, 281, 288, 320.
Barrande, 54.
Baumgärtner, Heinrich, 57, 176.
Blanchard, Emil, 54, 106.
Bleek, Wilhelm, 17, 96, 97, 194, 197, 234, 236.
Boerhave, 36.
Braubach, 226.
Braun, Alexander, 55, 176, 226, 246, 397.
Braun, Julius, 17.
Buch, Leopold von, 52.
Buckle, 17.
Büchner, Ludwig, 42, 118, 141, 158, 188, 205, 219, 233, 396.
Buffon, 31.
Carneri, 203, 238.
Carns, 36.
Christy, 90.
Condillac, 96.
Cotta, Bernhard von, 51.
Curtius, 96.
Cuvier, 31, 32, 34, 37, 320.
Darwin, 17, 18, 25, 27, 38, 118, 171, 177, 217, 240, 320, 389.
Descartes, 127.
Dillman, 295, 301.
Dohrn, 84.
DuBois-Reymond, Emil, 124, 125, 127, 130, 134, 149.
Ebrard, 159, 209.
Ecker, 56.
Escher, von der Linth, 54.
Farrar, 96.
Fechner, Gustav Theodor, 135, 146.
Fichte, Immanuel Hermann, 142, 175.
Fraas, Oskar, 55, 90.
Frohschammer, 175.
Gegenbaur, 56.
Geiger, Lazar, 17, 96.
Geoffrey St. Hilaire, Etienne, 32, 34.
Gerhard, 197.
Giebel, 54.
Göppert, 54.
Göthe, 33, 34, 35, 320.
Gray, Asa, 222.
Grusebach, 55.
Grimm, Jacob, 17, 95.
Häckel, 35, 42, 43, 45, 75, 78, 106, 123, 130, 133, 149, 159, 160, 166,
170, 204, 219, 234, 237, 281, 395.
Hartmann, Eduard von, 56, 60, 106, 131, 142, 168, 176, 191, 205, 334,
376.
Heer, Oswald, 56, 176.
Hegel, 126, 136, 204.
Helmholtz, 136, 159.
Heyse, 96.
Hilgendorf, 82.
His, Wilhelm, 56, 81, 106.
Huber, 175.
Humboldt, Wilhelm von, 17, 95.
Huxley, Thomas, 42, 50, 177, 198, 222, 279.
Jäger, Gustav, 51, 124, 214, 243.
Jellinghaus, 94.
{15}
Kant, 195, 282.
Keim, 18, 337.
Kölliker, 56, 81, 176.
Köstlin, Julius, 175, 187.
Köstlin, Otto. 149.
Kowalewsky, A., 42.
Kowalewsky, W., 83.
Kurz, Johann Heinrich, 306.
Lamarck, 27, 30, 31, 33, 320.
Lang, Heinrich, 197, 210.
Lange, Friedrich Albert, 112, 168, 173, 176, 194, 196.
Lartet, 96.
Leibnitz, 127, 217.
Leidy, 83.
Lessing, 405, 407.
Linnaeus, 30.
Livingstone, 93.
Lotze, 142, 145, 149.
Lubbock, Sir John, 18, 91, 93, 242.
Lyell, Sir Charles, 18, 36, 55, 89, 90, 222.
Mädler, 177, 252.
Malthus, 39.
Marsh, 83.
Martensen, 187.
Mayer, Robert von, 37, 129, 149, 155.
McCosh, 224.
Mill, John Stuart, 242.
Mivart, 55, 106, 223, 245.
Moleschott, 42.
Müller, Fritz, 79.
Müller, Max, 18, 96, 98.
Murchison, Sir Roderick, 54.
Nägeli, 56.
Nitzsch, Karl Immanuel, 361.
Noiré, Ludwig, 281.
Oken, 34, 320.
Owen, Richard, 35, 56, 164, 176, 221, 223, 320.
Peschel, Oskar, 279.
Pfaff, 54.
Pfleiderer, Otto, 187.
Planck, Carl Ch., 105, 110.
Preyer, 136, 146, 153.
Rathke, Heinrich, 81.
Reichenbach, 42.
Renan, 18.
Réville, Albert, 334.
Ritschl, 364.
Rütimeyer, 56, 83.
Sandberger, 55, 82.
Schaaffhausen, 56, 85, 177.
Schelling, 109.
Schiller, 180.
Schleicher, 17, 96.
Schleiden, 42, 51.
Schleiermacher, 190.
Schmidt, Oskar, 33, 35, 51, 75, 124, 159, 164, 191, 234.
Schopenhauer, 128, 190.
Schrader, Eberhard, 345.
Seidlitz, 51, 159, 238.
Semper, Karl, 84, 131.
Snell, Karl, 42, 262.
Spencer, Herbert, 128, 139, 194, 242, 279.
Spinoza, 204.
Stael, Madame de, 234.
Steffens, 109.
Steinthal, 17, 96.
Strauss, David Friedrich, 18, 112, 125, 128, 159, 163, 174, 175, 190,
213, 234, 337, 376, 394.
Swammerdam, 36.
Tait, 138.
Thomson, Sir William, 138.
Trümpelmann, 209.
Tübingen School, 18.
Tylor, 91.
Ulrici, 142, 144, 149, 175, 235.
Virchow, 56, 85.
Vischer, Friedrich, 175, 176, 213, 264.
Vogt, Karl, 42, 56.
Volkmann, A. W., 56, 105, 177.
Wagner, Moriz, 52, 56.
Wallace, Alfred Russell, 37, 101, 177, 221, 262.
Wedgewood, 96.
Weismann, 56.
Wigand, Albert, 26, 52, 56, 57, 106, 135, 149, 170, 226.
Wundt, 142.
Würtemberger, 82.
Zittel, 56.
Zöllner, 128, 129, 131, 138, 139.
* * * * *
{17}
THE THEORIES OF DARWIN,
AND THEIR RELATION TO
PHILOSOPHY, RELIGION, AND MORALITY.
* * * * *
INTRODUCTION.
With the appearance of Darwin's "Origin of Species," on the 24th of
November, 1859, a new impulse began in the intellectual movement of our
generation. It is true, the whole theory advocated and inaugurated by
Darwin is, in the first place, only one of the many links in the long chain
of phenomena in the realm of the intellectual development of our century,
all of which have the same character, and give their stamp to the entire
mental work of the last decades. This stamp consists in the tendency of
science, which has nearly become universal, not only to consider all
phenomena, both of the physical and the mental life, in connection with
their preceding conditions in space and time, but to trace them back more
or less exclusively to these conditions, and to explain them exclusively by
means of the same. What a Wilhelm von Humboldt, and, still more, a Jacob
Grimm, prepared the way for in the realm of philology, a Lazar Geiger and a
Steinthal, and (under direct influence of Darwin) a Schleicher and a
Wilhelm Bleek further developed; what Julius Braun did in the realm of the
history of art; what a Buckle and a Sir {18} John Lubbock tried to do in
the realm of the history of civilization; what a Max Müller did in the
realm of the history of religion; what the Tübingen School began and its
disciples carried out in the realm of the exegesis of the Bible; what a
Strauss and a Renan, and in a certain sense also a Keim, did in the realm
of christology; what, finally--without being so closely connected with
individual names--was also done in the realm of the world's history: this,
Darwin did in the realm of the history of the organic kingdoms, seconded by
the geological principles of Sir Charles Lyell and by the investigations in
biology and comparative anatomy of a number of scientists. From this point
of view, the movement which was inaugurated by Darwin seems to us but the
reflex of the universal spirit of the present time upon a particular realm;
namely, that of natural science. But since, soon after the appearance of
the before-mentioned work and long before the publication of Darwin's
"Descent of Man," man also was included in the consequences of the
evolution theory, and his existence was explained as a wholly natural
development out of lower animal forms; since Darwin himself unreservedly
adopted this theory of the descent of man from the animal world as an
entirely natural consequence of his doctrine of the origin of species, the
evolution question has gone far beyond the proportionately narrow and
limited bounds of natural philosophy and of merely theoretical scientific
interest--has surpassed in interest all the before-mentioned
investigations, however lively this interest was and is to-day, and has
stirred up the minds of all most thoroughly, not only in their scientific
but also in their religious and ethical depths, some in {19} acknowledgment
and admiration, others in aversion and repugnance, and only a few in sober
and unprejudiced judgment. While some see in Darwinism the flambeau which
now lights mankind to entirely new paths of truth, and also to spiritual
and moral perfection, others see in it only an unproved hypothesis,
threatening to become the torch which might change the noblest and greatest
acquirements of the culture of past centuries into a heap of ashes; while
some date from it a new period of culture, others see in it a deep descent
of the present from the scientific, religious, and moral height which
mankind has ascended.
Under these circumstances, it has become an impossibility for religion and
the moral interest as guardians of the highest and most sacred acquisitions
of mankind, and still more for theology and ethics as the scientific
representations of religion and morality, to remain idle spectators. It
would certainly be more agreeable to them, and more profitable, if they
could delay their judgment until the question became better cleared up. For
the whole question presented by Darwin has not yet passed beyond the stage
of problems and attempts at solution; and there is always something
unsatisfactory in being compelled to deal with theories which in their
fundamentals are still hypotheses. But since all tendencies of the present
which are hostile to Christianity and to the theistic view of the world,
from the most extreme materialism up to the most sublime monism (as
pantheism and materialism of to-day have begun to call themselves),
seemingly with the confidence of complete victory, take possession of
Darwinism as the solid ground from which they hope to destroy all and every
belief {20} connected with faith in a living creator and master of the
world, it has also become impossible for those to whom the religious and
ethical acquisitions of mankind are a sacred sanctuary to take any longer a
reserved and expectant position. Silence now would be looked upon only as
an inglorious retreat; and thus nothing remains but openly to face the
question: What position must religion and morality take in reference to the
Darwinian theories?
In order to treat of the question with that objectivity which it requires,
we have to begin with a synopsis of the theories themselves. In this
representation we have to discriminate strictly between the merely
scientific theories and the naturo-philosophical and metaphysical
supplements and conclusions which have been brought into connection with
them. For precisely in the mixing of the most different problems which are
to be considered here, lies the main cause of the confused and superficial
judgment which is so often heard upon these questions.
* * * * * {21}
PART I.
* * * * *
THE THEORIES OF DARWIN.
* * * * *
{23}
BOOK I.
THE PURELY SCIENTIFIC THEORIES.
* * * * *
THE SCIENTIFIC PROBLEM.
The interesting problem which underlies Mr. Darwin's theories is the answer
to the question: _How did the different species of organic beings on the
earth originate?_ We find ourselves in the midst of an endless variety of
organic beings, animals and plants; we see ourselves, so far as regards the
entire physical part of our being, in relationship with this organic
world--especially with the organization and physical functions of the
animal body. The organic individuals come and go. They originate by being
begotten by and born of individuals of the same kind, or they spring up
through the formation of germs and buds; and they produce in the same way
new individuals, that resemble them in all essential characteristics. Like
always begets like, so far as our observations go. But not only the
individuals, but even the species to which they belong, must have
originated at some definite period of time--and, indeed, as geology tells
us, not all at once, but in a long series, which stretched through
immeasurable epochs of the earth's history. Thus we come face to face with
the question, already put, which we can now formulate more {24} precisely:
_How did the first individuals of each organic species come into
existence?_
No human being ever has observed, nor ever could observe, the origination
of a new species, because man, as it seems, did not appear on the earth
until all the other organisms were in existence. For this reason, the
scientists for a long time thought it unprofitable to occupy themselves
with this question; and even in our time a great many of them declare the
question to be absolutely insolvable, and every attempt at answering it to
be an unjustifiable use of hypotheses. But the impulse toward investigation
admits of no limitation so long as there is any probability of extending
its field of action. Especially in the province of nature, so many things
which could not be discovered by mere observation have been traced
indirectly, and so many important and established facts have been added to
our stores of knowledge, by first starting from hypothetical premises, that
man has again and again endeavored to approximate an answer to the question
of the origin of species by taking the indirect course of hypothesis and
induction, whenever the direct way of observation did not lead to any
result. Religion of course gives a solution to the problem by stating that
the species have been originated by the creative act of God. It is wrong to
say that this solution is opposed to the above-mentioned impulse toward
investigation; for this solution suffices for religion, whether a natural
progress in the origination of species be established or not. For, to the
believer in religion, the whole universe, with all its objective phenomena
and growth, is the work of God as well as the individuals of the already
existing species; and a {25} closer acquaintance with the manner of their
origin is not only no disturbance to his ground of belief, but, on the
contrary, an addition to his knowledge of the method of God's action. In
every man of sound mind, the religious faith is not antagonistic or even
indifferent to the scientific impulse toward investigation, but stands upon
a most intimate footing with it. Hence the human intellect again and again
makes the attempt to find an answer to the problem of the origin of species
in a scientific way, and each endeavor of this kind necessarily ends with
the dilemma that either the first individuals of a species, no matter
whether it be the highest or the lowest, have been evolved out of inorganic
matter, or they originated by descent from the most closely related species
of their predecessors. The denial of the first part of our dilemma, and the
affirmation of the second, is the "Theory of Descent."
But this theory of descent leads us at once into another dilemma. If the
species originated by descent from the most closely related lower species,
and under certain circumstances also from species of the same rank, and
even by degeneration from the next higher, it must have occurred in one of
two ways: either by leaps--called by naturalists "metamorphosis of germs"
or "heterogenetic conception"--or by a succession of imperceptibly small
alterations of the individuals from generation to generation. Each of these
changes would have been no greater than the differences we observe to-day
between the individuals of the very same species, but became in the course
of time so massed and strengthened in one direction that new species have
been evolved. This hypothesis is called the "Theory of Development," {26}
or "Evolution." We retain this name, although well aware of the fact that
the authors do not agree in their use of the term "evolution." Professor
Wigand, who adopts only the theory of a descent from one primordial cell to
another, and who positively rejects the idea of a progress from one fully
developed species to another, claims among other things that one value of
his own theory is that he secures for the idea of evolution its full
meaning. The expression still has a meaning for those who reject the real
descent of the species or their primordial germs one from another, and
acknowledge only the ideal bond of a common plan in their successive
manifestations. But as soon as we examine more closely the literal and
logical meaning of the word, we shall find it of most weight when we
understand by it the before-mentioned gradual evolution in opposition to
the theory of progress by leaps or new creations. Moreover, it is well
known that long before this no other term than evolution was used to
designate the growth of a single organic individual from the primordial
cell and egg to its fully developed form and vital function. Besides, we
find ourselves also in harmony with most of the authors, so far as they
have distinct conceptions of the different scientific problems, if we use
the term "theory of evolution" for the gradual development of one species
from another, in opposition to the hypothesis of a metamorphosis of germs,
or even of a genealogy of primordial cells.
But each evolution theory leads again to new theories, as soon as it has to
be proved in a scientific way. For it can claim a scientific worth only
when sustained by earnest attempts to find and prove the {27} productive
power, agencies and laws of such an evolution of species. Those attempts
can be made in various ways. As a philosophical question, many attempts at
solution have been made, both in ancient and modern times; but being mainly
in the realm of metaphysics, they do not come within the limits of our
scientific essay. As a question for investigators of natural phenomena,
only two attempts of sufficient importance to be mentioned have been made.
The first one was made by Lamarck, who, taking the really different ideas
of descent and evolution as one, made use of the hypothesis of
transmutation; thus becoming the pioneer of Darwinism. The other attempt
was made by Darwin in his theory of natural selection, or struggle, for
existence, and is called the "Theory of Selection."
In defining our problem, therefore, we find ourselves under the influence
of a scientific law of development. The simple problem which we started
from has developed into a trinity of problems and attempts at solution. The
simple question of the origin of species led us into the dilemma of a
_generatio æquivoca_, or a descent; the hypothesis of a descent led to the
dilemma of a heterogenetic conception, or an evolution; and the hypothesis
of an evolution rendered necessary the attempt at explaining this
evolution, and showed Darwin's method of explaining it by his selection
theory. It will be well for the reader to keep distinctly in mind the
difference between these problems and theories, in following our
investigations, even if we cannot arrange our historical sketch according
to the natural principle of division arising from these differences.
For it lies in the nature of the question itself, that {28} these theories,
in their historical progress, did not appear singly, but together. Those
who inclined to the theory of a descent of species could claim for it the
attention of scientific investigators only after having also made the
attempt at conceiving this descent in a concrete way, and according to
certain analogies of observation. The only analogy of the kind appeared in
the sphere of individual development and individual differences on the one
hand, and in that of closely related characters of allied species on the
other; and thus led of itself to the evolution theory. As soon as the
naturalists thought they had found the causes of such an evolution of the
species, they naturally placed these causes in the foreground of their
demonstrations, and erected upon them the structure of their entire theory;
thus treating descent, evolution and selection as one single and
indissolubly connected theory. But this manner of treating the question had
also its dangers, which have already caused a great deal of confusion and
misunderstanding, as well as much unprofitable controversy. Often friends
and enemies of the theories placed that which was in favor of the theory of
descent to the credit of the evolution or selection theory; and, on the
other hand, that which seemed opposed to the selection theory was often
held to be a weakening of the evolution and descent theory; and this was
done, not only by amateurs, but often enough by the highest authorities
also. In reality, however, it is quite conceivable that the idea of a
descent may prove correct, and possibly the idea of an evolution of the
species will have to be replaced by that of a heterogenetic generation, or
by the theory that certain groups in the organic system are originated {29}
by heterogenetic generation, and others by evolution; and so the evolution
theory must share with the theory of heterogenetic generation, or of a
metamorphosis of germs. On the other hand, it is conceivable that even
where the evolution theory is confirmed, the evolution can be accounted for
wholly or partly by other reasons than those derived from the selection
theory. And even this result of present investigations is not
inconceivable: that the reasons for and against the different theories will
be found to balance one another to such a degree that they will sooner or
later lead science, in answering the question of the origin of species, to
the old confession of Socrates--"_Ignoramus_."
We shall, therefore, have to arrange our historical sketch according to the
historical order of the appearance of the theories, and treat the problems
more or less as an undivided whole. But we shall keep in mind, during our
historical sketch, not only the logical separation of the problems in
question, in order not to lose clearness of judgment, but we shall also at
the end of our review, if we consider the present condition of the
problems, have to examine the same once more in detail, so far as regards
the above mentioned separation.
* * * * *
{30}
CHAPTER I.
RISE OF THE DARWINIAN THEORIES.
§ 1. _Direct Predecessors.--Lamarck._
The first man who gave direct expression to the idea of a successive
generation of the species through transmutation, and who attempted to
follow it up in a scientific way, was the French naturalist and
philosopher, Jean Lamarck, born 1744. In the year 1801, and subsequently,
he published his views, first in smaller essays and afterward more in
detail in his "_Philosophie Zoologique_," which appeared in 1809, and in
the first volume of his "_Histoire Naturelle des Animaux sans Vertèbres_,"
published in 1815. In these works Lamarck upholds fully the descent and
evolution theory, and maintains that the simplest organisms are generated
through a _generatio spontanea_, which is still taking place; but that all
the more developed organisms, including man, are descended through a
gradual change from other species. With this theory, he put himself in
direct and conscious opposition to the old doctrine of the immutability of
species and their characteristics, which had been ably maintained by
Linnæus, and also made some attempts at explanation which approach very
nearly the selection theory. A change in the physical conditions of life,
especially the force of habit in the use or disuse of the organs, the
inheritance of physical and psychical {31} qualities thus attained, and the
extension of the process of transmutation into extraordinarily long periods
of time with very slight changes, are also, in his view, the probable
causes of the variation and development of the species. He only lacks the
idea of a natural selection in the struggle for existence, and the
comparison of the processes in nature with the methodical selection of man
in the breeding of domestic animals and plants, to identify his views with
those of Darwin.
At first, Lamarck met only with violent opposition; but after a little
while his views ceased to attract attention. The time had not yet come to
make such an attempt at observing nature from the standpoint of evolution.
The sciences which favor such a mode of observation, and even demand
it--such as comparative anatomy and physiology and the history of the
development of the different plants and animals--were only in their
infancy, or were--like palæontology and the comparative geography of plants
and animals--not yet in existence. The influence of Linnæus, whose views
diametrically opposed those of Lamarck, predominated over all the
investigations of natural science; Buffon, who favored the ideas of
Lamarck, and loved to trace a unity in natural phenomena, was too instable
in his investigations and views to arrive at a comprehensive principle; and
even the eminent naturalist, Cuvier, of Montpellier, showed in his
observation of nature a predilection for analysis rather than synthesis,
and although his comprehensive mind inclined to generalize and explain, he
placed himself in decided opposition to a theory which was founded only on
a few decisive facts.
This last mentioned deficiency seems to have been {32} the main cause of
Lamarck's views soon being lost sight of. They nowhere found a support in
facts; the force of habit played in them an exaggerated and unnatural
_rôle_; the different illustrations of them--such as the long neck of the
giraffe explained by the permanent and inherited habit of browsing on the
branches of high trees, or the web on the toes of frogs, swimming-birds,
etc., explained by the habit of swimming--were talked about and laughed at
more as curiosities than as worthy of serious consideration.
Only twice after this did the question put by Lamarck attract wider
attention from the learned world. The first time was when, in 1830, the
bitter contest arose at the Academy of Paris, between Cuvier and Etienne
Geoffrey St. Hilaire, the father of Isidor G. St. Hilaire. Geoffrey St.
Hilaire had views similar to Lamarck's, but reached them from quite a
different standpoint--from the observation of the analogy and homology of
the organs; and accounted for the variation of species, not by the use or
disuse of the organs, but on the one hand by the common original type of
the organs, and on the other by the varied influence of the
surroundings--the _monde ambiant_. Lamarck himself seems not to have been
mentioned in this contest. The controversy turned much more on the question
whether in observing nature we can proceed by synthesis and find in the
analogies of the organisms the principles for explaining the real
connection between the different organic forms, or whether the analytical
process is the only correct one, and the synthetical should be discarded.
The solution of it will probably be, that the one process must be
supplemented by the {33} other, as Goethe has already shown in his account
of this controversy; but at that time it was decided in favor of the
analytical principle, and the question was for the time dropped. It came up
for a second time, but created little excitement, in 1844, when an
anonymous work, "Vestiges of the Natural History of Creation," directed the
attention and the interest of scientists again to Lamarck and his doctrine.
But this interest also soon came to an end, until through Darwin's first
publication the half-forgotten man again suddenly attained great honor.
Those who wish to form a closer acquaintance with the different advocates
of the evolution theory before Darwin's appearance, will find them
carefully arranged in the historical sketch which Darwin gives in the
introduction to his work on "The Origin of Species"; and the most important
extracts of Lamarck's "_Philosophie Zoologique_" are to be found in Oscar
Schmidt's "Descent and Darwinism."[1]
§ 2. _Indirect Preparations._
While thus the ideas of Lamarck gradually fell into partial oblivion, yet
contemporaneous with and following them arose several other series of
thoughts, views, and investigations, which, although they only indirectly
prepared for the revival of the evolution theory, yet exercised a deeper
and more lasting influence on the minds of scientists. We refer to the
ideas in regard to natural phenomena held during the first decades of our
century; further, to the principles of comparative anatomy which, up to the
present time, partly dependent {34} and partly independent of natural
philosophy, have been expressed, valued, and admired as leading thoughts;
and, lastly, to the empiric results of comparative anatomical and
biological investigations in palæontology and geology, as attained by the
help of those very principles. And even physics and astronomy had to
coöperate in preparing the way for the idea of evolution.
The philosophical ideas referred to, together with the points of view and
results of comparative anatomy, led more and more decisively to the idea of
an _original form_, or _type_, which retains its identity in all the
modifications of form in plants and animals; and of a _ground-plan_, which
is realized in the systems of the plant and animal world in higher and
higher differentiations and in more and more developed modifications,
diverging farther and farther from the prototype until it reaches its
highest form, still reducible to the prototypes, in the most highly
organized dicotyledons in plants, and in the animal world in the mammalia,
and lastly in man.
Men like Cuvier and Geoffrey St. Hilaire, who otherwise stand diametrically
opposed to each other, unite in these and kindred ideas. The naturalist
Oken attains the same result, tinged with the views of Schelling; the poet
Goethe, from an intuitive knowledge of nature, arrived at the same
conclusion. The former, during a journey in the Hartz Mountains, at the
sight of a bleached deer's skull, and the latter, upon picking up a sheep's
skull in the Jewish cemetery at Venice, were struck by the same thought:
the skull is only a modified vertebra. Oken founded upon this idea and
kindred analogies his profound philosophy of the system of animals and
plants which comes very near to the evolution {35} theory, and in his
cosmogony traces all organisms to a protoplasm in such a way as to bring
him in this respect also very near to Darwinism. Goethe, in his
metamorphosis of plants, develops ideas in which, in all seriousness, he
makes a concrete application of his thought of a prototype to the leaf of a
plant; and proved for zoölogy the fruitfulness of his idea of a type by his
well known discovery of the mid-jaw bone in man. Although Oscar Schmidt
seems to be decidedly right in supposing, in opposition to Ernst Häckel,
that Goethe did not intend to have his idea of unity and development taken
in a real but in an ideal sense, and hence could not be called a direct
representative of the evolution theory, still he is all the more decidedly
a predecessor of that theory in directing attention to the unity in plan
and metamorphosis of plants and animals. Louis Agassiz, who, on the other
hand, continued up to his death in opposition to the entire doctrine of
descent, made the idea of _types_ the principle of his whole
classification, and said: "Man is the purpose toward which the whole animal
creation tends from the first appearance of the first paleozoic fish."
Richard Owen, who rejected the selection theory and favored that of
descent, published, long before Darwin's appearance, some most interesting
results of his anatomical and palæontological investigations from the point
of view of the prototype and its modifications. "Man, from the beginning of
organisms, was ideally present upon the earth," is a sentence which we
quote from Owen's works.
In short, this ideal momentum in the observation of the organic kingdoms is
not only the most beautiful blossom and the ripest fruit of the union
between {36} laborious and comprehensive detailed investigations and a
generalizing philosophic penetration, but it was also a very efficient
preparation of the mind for the evolution problem, so far as the summing up
of the organisms under a type and plan is only the ideal reverse of its
realistic reduction to a common pedigree.
We have yet to add the investigations in regard to the history of evolution
of the single organisms, as well as those in comparative anatomy, which in
former centuries were begun by scientists like Swammerdam and Boerhave and
carried more nearly to completion by K. E. von Baer, Carus, and others. In
reducing all the tissues of plants and animals to one cell, and tracing
back also their individual developments to the first differentiation of the
simplest cell, they followed out the unity of the plan of the organic
kingdoms--which hitherto had been maintained only ideally and proclaimed as
a philosophic postulate--farther and deeper into the sphere of empiric
reality. We must mention, moreover, the great palæontological discoveries
which, from the first foraminifera of the Cambrian formations up to the
historical period of man, showed a great progressive scale in the
appearance of the organisms and a very wide relationship between this scale
and the natural systems of botany and zoölogy; and, finally, the principles
of geology, which, under the leadership of Sir Charles Lyell, starting from
the idea of an identity of the powers which were active in former times
with those of the present, attempted to explain the most violent of the
changes in the earth's crust in former times by causes active to-day. This
often explains prodigious effects--such as the elevation and settling of
entire mountains {37} and continents--by the constant and related action of
the slightest causes and most gradual steps; it opens the perspective into
vast epochs of long and numerous geological periods; and sometimes, where
scientists like Cuvier and Agassiz have supposed the most complete
cataclysms and the most universal revolutions of the globe, there prove to
have been only gradual changes with revolutions very partially and locally
limited.
Finally, if we take into consideration the grand discoveries which
strikingly illustrate the connection in extent and quality between the
universe and all its agencies and powers--such as Robert von Mayer's
discovery of the conservation of force and of the mechanical equivalent of
heat, or the spectrum analysis and the information which it gives us by
ever-increasing evidences of the identity of the cosmic and telluric
substances--we may venture to say that the scientific and intellectual
ground was well prepared for a theory which takes the origin of organisms
into this common relationship of the essential unity and development of the
universe.
Only one thing more remained to complete the hypothesis offered by Lamarck,
of the _fact_ of a development of species by a new and more satisfactory
answer to the question as to the _manner_ of their development. The task of
answering in a more comprehensive and scientific way the question as to the
manner of development has been undertaken by Darwin in his selection
theory. Alfred Russell Wallace, who arrived at the same results
contemporaneously with and independently of Darwin, has, with praiseworthy
modesty, renounced his claim to priority of the discovery, as Darwin had
been longer engaged in working out his theories and had begun to collect
materials for proof.
* * * * * {38}
CHAPTER II.
HISTORY OF THE DARWINIAN THEORIES.
§ 1. _Darwin._
In order to explain the development of higher species from lower ones in a
natural way, Darwin starts from two facts. The first fact is, that all
individuals of the same species show, besides their specific similarity,
individual differences: a fact which we call the _law of individual
variability_. The other fact is, that each individual inclines to transmit
to his offspring all his qualities--not only the characteristics of the
species, but also those of the individual: a fact which we call the _law of
heredity_.
To show how the whole basis of explanation of the evolution of one species
from another is given in these two facts, Darwin calls attention to the
rules according to which the often extraordinarily great varieties of
domestic animals and cultivated plants are obtained and preserved; namely,
the rules of _artificial breeding_. The breeder simply selects from a
species those individuals having such individual qualities as he wishes to
preserve and to increase, and refrains from breeding those individuals
which do not possess the characteristics he wants or which possess them
only in a small degree. He continues the same process with the next
generation; and by the constant and effectual agency of the two {39}
before-mentioned laws, he will, after the lapse of a few generations, have
breeded a variety in which the characteristics originally belonging only to
a single individual have become common and permanent.
It is now important to consider whether nature, in _natural selection_
(whence the name "Selection Theory") does not act unconsciously according
to the same rules, and attain the same results, as man with his artificial
and intentional selection; and, furthermore, whether she does not reach
results which, according to that principle of natural selection, finally
explain the origin of all, even of the highest and most complicated
organisms, from one single original form or a few original and simplest
forms. Darwin finds these questions answered in the affirmative; and
arrives at this answer through the following conclusions.
The English political economist Malthus (1766-1834), in his "Essay on the
Principles of Population," established a law in regard to the growth of the
human race, which may be applied just as well to all the species of the
entire organic world: that population tends to increase in a geometrical
ratio, although the conditions of life for the individual remain the same
or at most increase in an arithmetical ratio. The consequence is that if
the species is to be preserved and the individuals of future generations
are to continue to find sufficient food and other means for sustaining
life, a great many individuals of each generation must perish very early,
and even as germ and seed, and only a minority will be preserved and
reproduced. This exuberant prodigality of life-germs, of which
proportionately only a few are preserved and reproduced, takes place in the
plant and {40} animal world in a very marked degree. There a continual
_struggle for existence_ prevails; each individual has to get access to his
conditions of life by wresting them from a whole series of other
individuals of his own or other species; and now the question arises: which
individuals will survive in this struggle? which will more probably be
preserved and procreate offspring? Evidently, the answer is, those
individuals which possess individual characteristics more favorable to the
preservation of the individual than those possessed by other individuals.
These individual characteristics are transmitted to the next generation. In
this there will be again individuals that have in a still higher degree the
characteristics thus transmitted and favorable for the preservation of the
individual, or that add to these favorable characteristics new
characteristics favorable in another direction to the survival of the
individual in the struggle for existence. While these individuals, with
more probability than the others, are thus preserved and reproduced, they
transmit to their offspring not only the old favorable characteristics
increased, but also those newly added. Among the favorable individual
qualities, Darwin reckons the divergence of character, the perfection of
organization, and the law of correlation; the latter, however, can not be
explained by natural selection, since according to this law a variation in
an organ brings about a corresponding variation in entirely different
organs (_e.g._, cats with white fur and blue eyes are also deaf).
This is _natural selection by means of the survival of the fittest in the
struggle for existence_. Changes in the conditions and surroundings of
life, and more or less {41} perfect adaptation of the organisms to the new
conditions of form, color, food and habit, are the main causes of those
individual variations, the accumulation of which through many generations
produces so great effects. If we only have behind us periods long enough to
permit us to imagine each step in the development as an extremely small and
hardly appreciable one, natural selection offers us not the exclusive but
the main means of explaining the evolution of the whole animal and plant
world out of one or a few simple organized original forms.
This is the outline of the selection theory, as given by Darwin in 1859,
and still retained in all its essentials. It is true, in his work on the
origin of man he added as supplemental the _sexual_ to the common natural
selection, and made it of special importance for the presentation of the
_beautiful_ in nature--for the production of beautiful forms, colors, and
tones, and for the development of power and intelligence. And in the same
work he said that there are many circumstances of structure which seem to
be neither beneficial nor detrimental to the individual, and that to have
overlooked this fact was one of his greatest mistakes in his former
publications. But for the rest, he maintains the selection theory
unchanged, with the single modification that it explains, if not the whole
development of the species through descent, at least that which is of most
importance in it.
That it was only one step in the course of reasoning to extend the
selection theory to the descent of man, was seen by many as soon as
Darwin's work on the origin of species was published and began to attract
{42} attention; although not a syllable upon this question was presented in
this work. Various persons manifested their presentiment or perception
according to their point of view--partly by the most violent opposition to
the new doctrine, partly by scientific development or modification of their
anthropogonic views, partly also by revelling in imagination in the
consequences hostile to religious faith which they thought could be drawn
from this doctrine. We remind the reader of the itinerant lectures of Karl
Vogt about the ape-pedigree of man, and of the echo they found by assent or
dissent in press and public; also of Huxley in England, Karl Snell,
Schleiden, Reichenbach, and others; of the materialists, L. Büchuer and
Moleschott, and of the publications of Ernst Häckel. Finally, Darwin
himself made us fully certain of the importance which from the beginning he
had attributed to his theory, by publishing his work on the "Descent of
Man," in the year 1870.
In this work he explained the descent of man fully from the before-named
principles of the descent, evolution, and selection theories, of which we
have given all the essentials in the foregoing presentation. He carefully
enumerates everything in the structure of the human body that reminds us of
our relationship with the animals--especially those embryonic phenomena and
rudimentary organs in man which are still to be found in use and in a more
developed state in different animal species, and which led him to imagine
our ancestors now with a tail, then with sharp ears, now living in the
water, then being hermaphrodites. He reviews the spiritual qualities of
man, and finds for them all analogous qualities in the animal world. He
finds in his work on {43} "Expression of the Emotions in Man and Animals,"
published in 1872, new confirmation of the genealogical relationship of
both. He looks over the whole course of the zoölogical system and of
palæontological discoveries, and searches for the points where the branches
and twigs of the animal pedigree of man must have diverged. To begin with
the lowest branches, he thinks the most important divergence took place
where the series of vertebrates may have been developed out of the
invertebrates. Here he adopts the investigations of A. Kowalewsky, and the
deductions of Häckel founded upon them, concerning the larva of the
ascidiæ, a genus of marine mollusca of the order tunicata, and sees in a
cord, to be found in this larva, most decided relationship to the spine of
the lancelet fish or amphioxus, the lowest of all the vertebrates, it being
yet doubtful whether it belongs at all to the vertebrates. In the
transition that once took place from one species of ascidian larva to a
form similar to the lancelet fish, he sees the new branch diverging in the
series of vertebrates. Out of the fish he concludes that the amphibia were
developed, and out of those the reptilia, out of one of them the
marsupialia, and from them the lemurs or half-apes, the representatives of
which yet live in Madagascar and the southern part of Asia. From these
there branched off on the one side the platyrrhini, or apes with a flat
nose, on the new continent; on the other, the catarrhini, or apes with a
narrow nose, on the old. Among the ancestor of the last, he searches for
the common progenitors, from which again two branches started--on the one
hand the ignoble branches of the catarrhine species of apes, always
remaining lower in {44} development, to which also belong the
anthropomorphous apes, like the orang outang and gibbon in Asia, the
gorilla and chimpanzee in Africa; on the other hand, that branch which
represents the ascent of animals to man.
The refining agencies which finally raise the animal up to the man are
essentially the same that on the lowest scales of the pedigree have caused
the development of the lower organisms into the higher, namely: favorable
individual variations, inheritance, acclimatization, survival of the
fittest in the struggle for existence, natural, and especially, sexual
selection. These are, if not the exclusive, still the main agencies which
finally led the primate of the earthly creation upon the stage and
furnished him with his superior faculties. But it is particularly by means
of his social life, and of the forces which determine, transmit, increase
and ennoble the various impulses and instincts promoting it, that man has
become what he is. Through the need and faculty of reciprocal help, through
sexual selection--which of course is a very essential factor of social
life--there originated language, and reflection, and all the intellectual
qualities; and through these again originated the moral qualities, which
are most important in constituting the specific worth of man, and which
were finally developed into self-consciousness and free moral
responsibility.
But with the description of this attempt to explain more in detail these
specific characteristics of man, we leave the ground of pure natural
science and enter the region of philosophy, in which we have to take up the
{45} question again (in Book II, Ch. I) at the same point where we here
leave it.
§ 2. _The Followers of Darwin.--Ernst Häckel._
Darwin's theory soon found an enthusiastic corps of followers--on the
continent, and especially in Germany, almost more than in his own country.
The outlook into an entirely new explanation of the origin of man, and the
probable use of this theory for attacks upon faith in a Creator and Master
of the world, called wide-spread attention to it; and the theory opened to
natural science itself entirely new impulses and paths, and promised the
solution of many problems before which it had hitherto been compelled to
stand in silence. To be sure, it threatened likewise to allure the mind
from the slow but sure ways of solid study to the entertaining but insecure
and aimless paths of imagination and hypothesis.
Among all the German followers of Darwin who adopted not only the idea of
an origin of species through descent and evolution, but also the
explanation of evolution by natural selection, and extended it so as to
make the principle of selection of exclusive value, Ernst Häckel occupies
the most prominent rank.
In his "General Morphology," published in 1866, and in his "Natural History
of the Creation," the first edition of which appeared in 1868, and finally
in his "Anthropogeny"[2] (why he does not say Anthropogony, we are nowhere
informed), 1874, this scientist brought the new theory, which had been
presented by Darwin in an almost bewildering flood of details, into
connection and order, and, analyzing the powers active in natural
selection, combined them into an entire system of laws. He {46} at once
drew the origin of man also into the course of reasoning on the new theory,
and sustained the theory by the discovery of the _monera_ and other low
organisms of one cell, as well as by special investigations of the
calcareous sponges. For these labors, he was rewarded by the warm and
unreserved acknowledgment which Darwin made to him in his work upon the
origin of man, which was published subsequently to the "Natural History of
the Creation." There Darwin says: "If this work had appeared before my
essay had been written, I should probably never have completed it. Almost
all the conclusions at which I have arrived, I find confirmed by this
naturalist, whose knowledge on many points is much fuller than mine."
Häckel's labors rendered still greater service to the Darwinian theory by
dividing the organic world into three kingdoms: the protista kingdom, the
vegetable kingdom, and the animal kingdom,--a division which solves in a
most simple way the difficulty that was felt more and more of securing for
the lowest organisms a place among the animals or plants. He further aided
the theory by leaving the choice open to adopt either a uniform or
multiform pedigree of the organisms and their kingdoms and classes, and by
treating each class under both points of view; and finally, by fascinating
experiments to bring before us in detail the hypothetical pedigrees of all
classes of organisms from the protista kingdom up to man.
We will try to reproduce briefly the pedigree which is of most
interest--the hypothetical _pedigree of man_. Häckel divides it into
twenty-two stages, eight of them belonging to the series of the
invertebrates, and fourteen to that of the vertebrates. On this ladder of
{47} twenty-two rounds, he leads us from the lowest form of the living
being, in slight and mostly plausible transitions, continually higher and
higher, up to man; and makes our steps easy by mentioning at each stage, on
the one hand the corresponding state in the embryonic development, on the
other the still living creature through which, in his opinion, the former
organisms of the corresponding round of the ladder are still represented,
and which accordingly has been a creature that remained on its round, while
other members of its family have been developed up to man and to many other
genera and species.
He begins with the monera, the organisms of the lowest form, discovered by
himself, which have not so much as the organic rank of a cell, but are only
corpuscules of mucus, without kernel or external covering, called by him
cytod, and arising from an organic carbon formation. The lowest and most
formless moneron is the bathybius, discovered by Thomas Huxley, a network
of recticular mucus, which in the greatest depths of the sea, as far down
as 7,000 metres, covers stone fragments and other objects, but are also
found in less depths, in the Mediterranean Sea, for instance. From the
moneron he proceeds to the amoeba--a simple cell, with a kernel, which
still corresponds to the egg of man in its first state. The third stage is
formed by the communities of amoebæ (synamoebæ), corresponding to the
mulberry-yolk in the first development of the fecundated egg, and to some
still living heaps of amoebæ. To the fourth stage he assigns the planæa,
corresponding to the embryonic development of an albumen and the planula or
ciliated {48} larva. When these ciliated larvæ are developed, they contract
themselves so as to form a cavity; and this fifth stage--especially
important for his theory--he calls gastræa. In this form, he says, the
progaster is already developed, and its wall is differentiated for the
first time into an animal or dermal layer (ectoblast), and into a
vegetative or intestinal layer (hypoblast). At the sixth stage, there
branched off the prothelmis, or worms, with the first formations of a
nervous system, the simplest organs of sense, the simplest organs for
secretion (kidneys) and generation (sexual organs), represented to-day by
the gliding worms or turbellaria; as the seventh stage, the soft worms, as
he called them at first--the blood worms, or coelomati, as he describes
them in his "Anthropogeny"--a purely hypothetical stage, on which a true
body-cavity and blood were formed; the eighth stage are the chorda-animals
with the beginning of a spinal rod, corresponding to the larva of the
ascidiæ. At the ninth stage, called the skull-less animals (acrania), and
corresponding to the still living lancelet, we enter the series of the
vertebrates. The importance of the eighth and ninth stages for the theory,
we have already pointed out in our remarks upon Darwin, p. 43. The tenth
stage is formed by those low fishes in which the spinal rod is
differentiated into the skull--and the vertebral-column, called the
single-nostriled animals (monorrhini), and represented by the cyclostoma of
today (hag and lampreys). The eleventh stage is formed by the primæval fish
or selachii (sharks); the twelfth by the mud fish, of which there still
live the protopterus in Africa, the lepidosiren in the tributaries of the
Amazon, and the ceratodus in the swamps of Southern {49} Australia. On the
thirteenth stage, there are the gilled amphibians (sozobranchia), proteus
and axolotl; on the fourteenth, the tailed amphibians (sozura), newt and
salamander; on the fifteenth, the purely hypothetical primæval amniota or
protamnia (amnion is the name given to the chorion which surrounds the
germ-water and embryo of the three higher classes of vertebrates) on the
sixteenth, the primary mammals (promammalia), to which the present
monotremes (ornithorhynchus and echidna) stand nearest; on the seventeenth,
the pouched animals or marsupialia; on the eighteenth, the semi-apes or
prosimiæ (loris and maki); on the nineteenth, the tailed apes, or menocerca
(nose-apes and slender-apes, or semnopithecus); on the twentieth, the
man-like apes (anthropoides) or tail-less catarrhini (gorilla, chimpanzee,
orang outang and gibbon). And now we come to twenty-one--ape-like men or
speechless primæval men (alali)--of whom we are reminded to-day by the
deaf, and dumb, the cretins and the microcephali; and number twenty-two is
_homo sapiens_, the man. The Australians and the Papuans are supposed to be
the only remaining representatives of his first stage-development. In like
manner, Häckel also gives us the stem-branches of all the types, classes
and orders of the organisms, and forms from them a very acceptable
hypothetical pedigree; or--if we prefer to suppose a polyphyletic rather
than a monophyletic origin of species--hypothetical pedigrees of the whole
organic world.
The perspicuity and clearness of Häckel's deductions, the extent of his
knowledge, and the singleness of his aim, to which he makes them all
subservient, lend {50} to his works a great charm. But on the other hand we
dare not conceal that, even on the ground of explanations belonging purely
to natural history, the character of hypothesis is often lost in that of
arbitrariness and of the undemonstrable. Even the unlearned in natural
science often enough get this impression when reading his works, and will
find it confirmed by scientists who not only contradict his assertions in
many cases, but disclose plain errors in his drawings--errors, indeed,
exclusively in favor of the unity-hypothesis; and in other cases they show
that drawings which are given as pictures of the real, represent merely
hypothetical opinions. There is especially evident in his works an
extremely strong tendency to impress on his hypotheses the character of an
established and proved fact, by giving them the alluring name of laws.
Entire systems of laws of the selection theory are produced, and all
imaginable assertions are also immediately called laws. For example,
Huxley, in his anatomical investigations of apes and men, arrives at the
conclusion that the differences between the highest and the lowest apes are
greater than the differences between the highest apes and man. This purely
anatomical comparison, Häckel calls repeatedly "Huxley's Law." We are well
aware that the idea of law is capable of great extension in meaning, and in
that respect we can refer to nothing more instructive than the
well-meditated inquiry upon this idea in the "Reign of Law" of the Duke of
Argyll (London, Strahan & Co.). But if we may venture to call purely
anatomical comparisons of this nature _laws_, such a use of language
destroys all logical reasoning; and this mistake appears again in Häckel's
philosophic {51} discussions, of which we shall have to speak hereafter. We
shall have to refer also hereafter to an additional embellishment, which
Häckel thinks himself obliged to give to his works--namely, that he makes
on every occasion the strongest attacks upon faith in a personal God, a
Creator and Lord of the world; that he traces all the motives of human
action to self-interest; that he denies the liberty of man and the moral
system of the world; that he makes consent to his view of things the
criterion of the intellectual development of a man; and that he thinks to
render a service to civilization by such a view of the world and of ethics.
In the consequent carrying out of the selection principle as the
satisfactory key in explaining the origin of all species and also of man,
Häckel is indeed, in spite of the approval of his works by the British
master, more Darwinian than Darwin himself, who expressly refuses to give
exclusive value to this theory of explanation. Hence there are among
scientists only a few who go with him to this extent. In Germany, aside
from the materialists, we only know of Seidlitz and Oskar Schmidt--who in
the thirteenth volume of the "International Scientific Series" treats of
"The Theory of Descent and Darwinism," and advocates not only the autocracy
of the selection theory, but also all the monistic and atheistic
consequences which are deduced from it. Perhaps Gustav Jäger, Schleiden,
Bernhard Cotta--at least judging from their earlier publications--should be
mentioned as followers of the pure selection theory; although they do not
all draw from it the before-mentioned philosophic consequences. On the
other hand, the number of those is very great who, although inspired {52}
by Darwin to adopt the idea of an origin of species through descent and
evolution, yet have more or less modified, laid aside, or entirely refused
the very doctrine which is especially new in Darwin's theory--the selection
theory. In the following section we shall briefly give an account of them.
§ 3. _Modifications of the Theory--Moriz Wagner. Wigand._
One of the most prominent objections to the selection theory, which strikes
us at once from the standpoint of natural history, is the following: The
varieties of a domesticated species, obtained by artificial breeding, are
lost, and return to the original wild form of the species as soon as they
are crossed long enough with other varieties or are left to themselves and
to the crossing with individuals of the original form of their species; and
hence we can not see how individual characteristics, even if favorable to
the individual, will not be lost again by the crossing which is inevitable
in a state of nature, with such individuals as do not possess those
characteristics. Besides, it is an established fact, confirmed by all our
observations stretching over thousands of years, that the characteristics
of species are preserved in spite of all individual modifications, and that
this preservation of the characteristics of species has its cause
essentially in the free crossing of individuals.
This objection induced Moriz Wagner to take up again an idea already
expressed by Leopold von Buch, and to complete the principle of a selection
through natural breeding by another, and partly, indeed, to supplant it by
the principle of _isolation by migration_. Isolated individuals, who, from
any reason naturally to {53} be accounted for, leave the mass of their
fellows, can from the very consequence of this isolation transmit to their
offspring common individual characteristics which are not destroyed again
by the crossing with other individuals. They will especially fix and
transmit these individual characteristics, when they are favorable to them
for the conditions of existence in their new place of living, and these
individual characteristics will so much the more be increased and developed
in a direction favorable to the subsistence of the individuals in their new
place of living, as there are more closely connected with this isolation
variations in the conditions of existence, in climate, geographical
surroundings, food, and so on. He very attractively applies this theory
also to the explanation of the origin of man. According to his opinion,
even the nearest animal progenitors of man were isolated, and the isolating
power was the rise of the great mountains of the Old World, which took
place previous to the glacial period. One pair, or perhaps a few pairs, of
those progenitors were driven away from the luxurious climate of the torrid
zone to the northern half of the globe, and found their return cut off by
glaciers and high mountains; in place of a comfortable life on the trees,
necessity urged them to gain support from conditions less favorable to
existence, and necessity, this mother of so many virtues and achievements,
finally made man what he is. In following out these ideas, Moriz Wagner has
gradually and more and more decidedly given up the selection theory, and
opposed it by sharp criticisms.
This _migration_ or _isolation theory_ also found a degree of favor, but
subordinate in its nature. For it {54} can not and will not pretend to
solve the main problems. It only tries to explain how the individual
variations, already in existence, might have been preserved and perhaps
increased, and how new conditions of existence could have roused latent
powers; but not how these variations and these powers originated. Just as
little is the selection theory able to explain this; but it pretends to do
it, and hence we can easily comprehend how during the last few years a
constantly increasing number of voices, and more important ones, have been
raised against the selection theory. This opposition came not only from
those who--like Agassiz, Barrande, Emil Blanchard, Escher von der Linth,
Göppert, Giebel, Sir Roderick Murchison, Pfaff, and others--directly reject
each and every idea of descent on account of the difficulty in defending
the selection theory; or who--like Karl Ernst von Baer,[3] (the {55}
pioneer in the region of the history of individual development), like Oskar
Fraas, Griesebach, Sandberger, and others--generally take a more reserved
and neutral position, because of the uncertainty of the facts and the
inaccessibility of the problems; but it comes especially from those
scientists who are inclined to adopt an origin of species through descent
and even through development, yet refuse to explain it by the selection
principle, and look for the essential cause of the development in the
organisms themselves, without claiming to have themselves found these
causes. Among the most prominent advocates of this view, we may name the
late Sir Charles Lyell, Mivart, and {56} Richard Owen, in England; and in
Germany, Alexander Braun, Ecker, Gegenbaur, Oswald Heer, W. His, Nägeli,
Rütimeyer, Schaaffhausen, Virchow, Karl Vogt, A. W. Volkmann, Weismann,
Zittel, and here also Moriz Wagner, and among the philosophers, Eduard von
Hartmann. Many of these men are but little aware of the difference between
the two questions: whether, on the one hand, the adoption of the origin of
species through descent does not of itself involve the idea of a gradual
development of one species from another, almost unobservable in its single
steps; or, on the other hand, whether a descent of species through
heterogenetic generation in leaps and through a metamorphosis of the germs,
could be imagined. They consider descent and evolution as identical; and
this identification is explainable so long as we are not in a condition to
come nearer to the eventual causes of the supposed variation of species.
But men are not wanting who put these questions clearly and plainly, and
separate them distinctly from one another. Among them we may mention K. E.
von Baer, Ed. von Hartmann and Wigand; of the latter we will have occasion
to speak more in detail hereafter. Among them we find also scientists who
answer the question in the sense of a new-modeling of the species, of a
heterogenetic generation, and of a metamorphosis of germs. To this class
belong especially Oswald Heer--"Urwelt der Schweitz" ("Antediluvian World
in Switzerland"), Zürich, 1865, p. 590-604; Kölliker--"Ueber die
Darwin'sche Schöpfungstheorie," ("Darwin's Theory of Creation"), Leipzig,
1864; "Morphologie und Entwicklungeschichte des Pennatulidenstammes nebst
allgemeinen Betrachtungen zur Descendenzlehre," {57} ("Morphology and
History of the Development of the Stem of the Pennatulidæ, together with
General Remarks on the Descent Theory"), Frankfurt, 1872; and Heinrich
Baumgärtner--"Natur und Gott" ("Nature and God"), Leipzig, Brockhaus, 1870.
Heer has introduced into scientific language the term "new-modeling of the
species," Kölliker that of a "heterogenetic generation," and Baumgärtner
that of a "transmutation of the types through a metamorphosis of germs."
Baer also is not averse to adopting the latter.
The botanist, Albert Wigand, of Marburg, takes a peculiar position. On one
hand, the observation of the relationship of organic beings with one
another leads him to adopt a common genealogy, a descent; on the other, the
objections to adopting a descent of the species one from another appear to
him insurmountable. In the first place, he sees all the species everywhere
strictly limited--although in the second volume of his work, which appeared
after the preceding lines were written, he again warns against a one-sided
emphasizing of the invariability of species. In the second place, he sees
so clearly, through the whole organic world, the differences, nay, the
contrasts, of the species, in their building plan, in the numbers and
conditions and positions of their parts, and in their mode of development,
that it appears to him impossible to assume in the perfected organism a
production of germs which in a course of generations, by a process even as
gradual as possible, would grow into such an entirely new phenomenon as a
new, even closely related, species would be. But if we adopt the theory of
a heterogenetic generation, we explain by it the variety but not the
similarity of species; {58} for a heterogenetic generation would in the new
species make everything different from the old one--a conclusion, the
necessity of which it would be difficult to show. For these reasons, he
refers the descent of the organic beings, not to the series of the species,
with their individuals already specified and defined, but to the series of
_primordial cells_ living free in the water. The earliest primordial cells
represented only the common character of the _whole organic world_, and out
of them the primordial cells of the _animal_ and those of the _vegetable
kingdom_ were produced by dividing the cells; so that the first ones
embraced only the general and primitive characteristics of the whole
animal, the last ones those of the whole vegetable kingdom. Out of these
primordial cells of the two kingdoms, those of the _main types_
proceeded--(for instance, the primordial cells of the radiated animals, the
vertebrates, etc., the gymnosperms, the angiosperms, etc.); out of them
those of the _classes_--(for instance, the mammalia, the dicotyledons); out
of them those of the _orders_--(for instance, the beasts of prey,
rosifloræ); out of them those of the _families_ (canina, rosaceæ); out of
them those of the _genus_ (canis, rosa); and out of them those of the
_species_ (canis lupus, rosa canina). Only when the primordial cells of the
species had been produced, were they developed into finished
representatives of the species; and when once these primordial cells of the
species had been developed into finished and full-grown individuals of the
species, their transmission took place in the manner well known to us.
Wigand published his criticism of the Darwinian Theories in his larger
work, "Der Darwinismus und die Naturforschung Newtons und Cuviers,"
("Darwinism {59} and the Natural Science of Newton and Cuvier"),
Braunschweig, Vieweg, Vol. I, 1874, Vol. II, 1876, and his own attempt at
explanation in a smaller book, published at the same place in 1872: "Die
Genealogie der Urzellen als Lösung des Descendenzproblems oder die
Entstehung der Arten ohne natürliche Zuchtwahl" ("Genealogy of the
Primordial Cells as a Solution of the Problem of Descent; or the Origin of
Species without Natural Selection").
Whether this _genealogy of the primordial cells_ found any followers, we do
not know. None of the hypotheses thus far mentioned are so very far from
having analogies in experience. The idea of a first development of the
higher organisms out of their specific primordial cell, through all kinds
of conditions of larvæ up to the finished form, demands of us the
acceptance of monstrous improbabilities--(think, for example, of the first
men, who, originating from a human primordial cell, grow in different
metamorphoses of larvæ, first in the water and then on the land, until they
appear as finished men). Moreover, the hypothesis, in claiming that a
heterogenetic generation of one species from another must necessarily
nullify all similarity between the organism of the child and that of the
mother, is so little convincing, and shows--in the necessity of conceiving
the universal type of organisms, the type of kingdoms, of main types, of
classes, of orders, of families, of genera, and of species, as but
individual existences which, in the form of cells and before the existence
of the developed species, partly through many thousands of years, lead a
real empiric and concrete life--such an abstract synthetical construction
of nature, that {60} we are not astonished that the theory of the genealogy
of primordial cells stands almost alone. On the other hand, Wigand's larger
critical work rendered great service in clearing up the problems. It is
true, his judgment appears in many single cases not at all convincing,
since he often enough fights his adversaries with sophisms and deduces from
the views of Darwin and Häckel conclusions to which they certainly do not
lead. But in the majority of cases, his work is full of real convincing
power, and with the breadth of its philosophical view and with the
sharpness of its definitions, as well as with its abundance of philosophic
and especially botanical teachings and their ingenious application, it is
directly destructive to the use of the selection theory as the principal
key to the solution of the problems. Eduard von Hartmann describes the work
in his publication, "Wahrheit und Irrthum im Darwinismus," ("Truth and
Error in Darwinism"), as a mile-stone which marks the limits where
Darwinism as such passed the summit of its influence in Germany.
* * * * * {61}
CHAPTER III.
PRESENT STATE OF THE DARWINIAN THEORIES.
§ 1. _The Theory of Descent._
The historical retrospect of the Darwinian theories, from their purely
scientific side, leads us of itself to a critical review of their present
state. We can briefly indicate in advance the result to which it will lead
us, viz.: that the descent theory has gained, the selection theory has lost
ground, the theory of development oscillates between both; but that all
three theories have not yet passed beyond the rank of hypotheses, although
they have very unequal hypothetical value. We can best arrange our review
by beginning with that theory which is the most common, and which perhaps
may still have value when both the others find their value diminished or
lost: _the theory of descent_. From that we proceed to the _theory of
evolution_, and from this to that of _selection_.
The theory of descent is indeed at first sight exceedingly plausible, and
will probably always be the _directive_ for all future investigations as to
the origin of species. The organic species show, besides the great variety
of their characteristics and the unchangeable nature of these
characteristics, many other qualities which are common to them; and these
common characteristics are precisely those which are most essential. {62}
Moreover the higher the structure of the organisms which are
differentiated, the more numerous and more valuable will become the
evidences of similarity, and the greater also will be their distance from
the inorganic and from the lowest organisms of their class, their type, or
their kingdom. For instance, rose and apple-tree, elder and ash, wolf and
dog, goat and sheep, ape and man, are not only a great deal farther removed
from the mode of existence of inorganic bodies than the algæ, the monera,
and other low organisms, but they have also, in spite of the great interval
which separates them from one another and especially which separates man
from every animal, much more numerous and important points of contact than,
for instance, two families or genera of algæ or of mosses, of polyps or of
infusoria, have among one another. Now our imagination refuses to accept
the theory that the Creator, or nature, or whatever we wish to call the
principle generating the species, in producing the new species, laid aside
all those points of contact which are continually becoming more numerous
and more important, and produced instead, by ever widening leaps, the new
and higher species from the inorganic, which lies farther and farther from
them. On the other hand, the theory appears to us all the more plausible,
that every new species came into existence on that stage which is the most
nearly related to it, and which was already in existence. If we add
further, that the two old maxims of the natural scientists, _omne vivum ex
ovo_ and _omne ovum ex ovario_, have not been invalidated, in spite of all
the searching for a _generatio æquivoca_, and that, even if the origination
of the lowest organisms out of the inorganic could in future be {63}
proved, yet the truth of these maxims for all the higher organized
individuals is established as a fact without exception. Moreover, if we
take into consideration the fact that we can not at all imagine either the
origin or the first development of a higher animal or a human organism
without the protecting integument and the nourishing help of a mother's
womb, we may venture to say that each and every attempt to render the
origin of the first individuals of the higher species conceivable, leads of
necessity to the descent theory. We have either to reject, once for all,
such an attempt, as an unscientific playing with impossibilities, or to
accept the idea of descent. It is certainly the lasting merit of Darwin,
even if his whole structure of proofs should in the course of time show
itself weak, that he not only had the courage (as others had before him),
but also inspired scientists with the courage to trace the idea of a
descent of species in a scientific way.
To be sure, so long as we have no other proof of the descent theory than
the circumstance that we can imagine it, it will continue to be nothing
more than an ingenious hypothesis. We have, therefore, to look to the realm
of nature for more direct proofs; and we are there furnished with them.
They are presented to us by geology in connection with the botanical and
zoölogical systems, by geology in connection with vegetable and animal
geography, by comparative anatomy, and by the history of the embryonic
development of animals.
_Geology_ finds in the strata of the crust of the globe a large number of
extinct plants and animals of extraordinary variety; but all of them,
however much they {64} may differ from the organisms of to-day, are
completely in harmony with the _botanical_ and _zoölogical systems_ in
which we divide the still living organisms. Not only have by far the most
of the now extinct genera and species their family and stem-companions, and
many even their genera and species companions, in the living world, but
also those genera whose nearer relations are now extinct--as, for instance,
the club-moss-trees, the trilobites, the ammonites, the belemnites, the
sauria, the nummulites,--show still a very perceptible relationship with
living genera, and can be quite accurately included in the botanical and
zoölogical systems; nay, they even fill up gaps in it. The anatomical,
morphological, and, so far as we can judge, the physiological and
biological relationship of the fossil with living organisms, is so great
and comprehensive that in the present state of science a systematic botany
or zoölogy, that should only treat of the fossils or of living organisms
alone, would be imperfect. But the relationship of the fossil organisms
with the natural systems of botany and zoölogy is apparent not only in this
respect, but also in the fact that the single species during the long
periods of time which are shown by geology to have elapsed, came into
existence in a series, which again pretty closely corresponds to the
natural system of the organic kingdoms; and that the fossil representatives
of all classes and families, the nearer they come to the present world,
appear the more nearly related to the living organisms, so that the fauna
and flora of the ante-human time are lost in those of the human period by
transitions gliding from the one to the other. For instance, in the Miocene
formation of the tertiary epoch {65} we find thirty per cent. of species
still living to-day; in the Pliocene, even sixty to eighty per cent., and
toward its end even about ninety-six per cent. of species which are
identical with those now living.
A brief glance may still more closely illustrate this analogy between the
geological series and the organic systems. Plants and animals seem to have
appeared nearly at the same time, and at first in the form of the very
lowest organisms. The earliest plants found by geology belong also to the
lowest stage of the vegetable kingdom; they are the algæ. They are followed
again by higher cryptogamous plants, especially ferns and club-mosses. Only
at a later period flowering plants appear, among them being first the
plants with naked seeds standing lower in the systems, as the cycad-trees
and pine-forests; later, those with enclosed seeds, among them being again
first the monocotyledons, last the dicotyledons,--all of them precisely
corresponding to the botanical system. The same thing is true in the animal
kingdom. If the eozoon Canadense, found in the laurentian slate of the
Cambrian formation in North America, is really an organism and not an
inorganic form, the earliest vestiges of animal life we can find are the
rhizopodes or foraminifera; and these organisms belong to the lowest stage
of life--to that stage which forms a kind of undeveloped intermediate
member between the vegetable and animal kingdom, Häckel's kingdom of the
protista. The next oldest animal organisms found in the Cambrian formation
are the zoöphytes, and immediately above them the mollusca and the
crustacea. In the following Silurian period we find corals, radiata, worms,
mollusca, and crustacea, in {66} great number, also all the main-types of
the invertebrates; and in the highest Silurian strata there are also to be
found representatives of the lowest class of vertebrates, of fish, but
still of very low organization and little differentiated. That the five
main-types of the invertebrates seem to have appeared quite
contemporaneously, yet that the zoöphytes really appeared first, does not
contradict the before-mentioned law of a progress in the appearance of the
organisms from the lower to the higher. For in the zoölogical system also
these main-types of the invertebrates do not stand one above the other, but
by the side of each other: at most, the radiata, the worms, the mollusca,
and the articulata, take their places above the zoöphytes. Only within the
main-types, in the classes, orders, etc., do differences in rank take
effect; and even here, not without exception. What difference in rank, for
instance, is there between an oyster and a cuttle-fish? between a cochineal
and a bee or ant? and yet the first two belong to one and the same
type--the type of mollusca; and the last three to one and the same
class--the class of insects. The vertebrates rank decidedly above the
invertebrates; and in a manner wholly corresponding to this, the
vertebrates also appear after the invertebrates. Just as decidedly as to
their rank, the main classes of the vertebrates do not stand beside, but
above one another: above the fish stand the amphibia, above them the
reptiles, next the birds, and above them the mammalia. To this series of
succession also the geological facts seem to correspond pretty closely;
only long after the fish do the first amphibia and reptilia
appear--although it can not yet be decided which of these {67} two classes
has left its earliest traces. If the interpretation of the gigantic
foot-steps in the colored sandstone of North America, as belonging to the
cursorial birds, is correct, the first appearance of birds falls in the
time between the reptilia and mammalia; otherwise the first mammalia would
have appeared before the first birds. For if we find the first real bones
of birds only in the Jura and in the Chalk-formation, they are birds with
tail-spines and with teeth in the beak--hence still related to the reptilia
or the sauria. The first traces of mammalia to be found in the Upper Keuper
formation, and in the Jura, belong to the order of opossums or marsupialia;
_i.e._, to that order which (excepting the echidna and the ornithorhynchus
that, as so-called monotremeta, stand the very lowest in the class of the
mammalia, but are very scarce) occupies the lowest stage among the
multitude of mammalia. Only after them do the higher orders of mammalia
appear; and last of all organisms, man.
If we follow more in detail the appearance of the single organisms, some
remarkable modifications show themselves in the course of their appearance
and growth. We have heretofore mentioned the possibility of the appearance
of the mammalia before the bird. Another fact which deserves attention is,
that frequently the lowest representatives of a class or an order do not at
first appear where the highest representatives of the next lower class or
order are in existence, but with lower representatives of a preceding class
or order, viz.: such representatives of the same as are still less
differentiated and unite in themselves comparatively still more generic and
less specific characteristics--as for instance, the lowest and {68}
earliest amphibia, which do not appear at the same time and place with the
most highly organized fishes, but with fishes of still lower organization.
Moreover many groups of organisms show in earlier geological periods a
richness of development from which they have now fallen far away. For
instance, among the mammalia the pachydermata, among the reptilia the
salamander and newt, among the articulata the cephalopoda, are at present
remarkably reduced;--compare with the legions of ammonites and belemnites
of the secondary period the small number of nautilus and cuttle-fish of the
seas at the present day. A similar fortune was experienced by the ferns and
club-mosses which formed whole forests in the carboniferous period. Other
groups which once played a great _rôle_, are now wholly extinct; for
instance, the trilobites of the primary, the sauria of the secondary, the
nummulites of the tertiary periods. Now, all these modifications of
geological progress would entirely correspond to the idea of a pedigree to
which the descent theory traces back the whole abundance of forms of
organisms. As soon as we seriously accept the idea of a pedigree, each of
the two organic kingdoms would throughout form for its classes and species
not only one single straight line of descent, but a tree, the branches of
which are again ramified in a manifold way; a tree on which single
branches--as perhaps that of the class of birds--may leave the main-stem or
a main-branch, possibly being a branch destined to a higher development,
and on that account held back in the process of development; a tree,
finally, on which also branches and twigs can wholly or partly die off, as
those of the extinct or reduced groups of organisms. {69}
From the point where the geological formations approach the present time,
_plant_ and _animal geography_ also assists _geology_ in increasing the
weight of the reasons for an origin of organisms through descent. With the
tertiary period, the fauna and flora of the globe, which in former periods
had a nearly uniform character all over the earth and showed no climatic
differences, begin to separate according to climate, zones, and greater
continents. This separation becomes distinctly evident in the middle
tertiary formations, the Miocene, and much more distinctly in the higher
tertiary formations, the Pliocene. The animals, especially the higher
vertebrates, of the Pliocene formation on each continent or each larger
group of islands, correspond very closely to the now living animals of the
same geographical limit, with the exception of being generally of a much
larger size. The Pliocene animal world of mammalia of the three old
continents, for instance, corresponds exactly, through all its orders, to
the present fauna of Europe, Asia and Africa; and that on an average it was
built up more stupendously than that of to-day, we can see from the
cave-bear and the mammoth. South America is the home of a peculiar order of
mammalia--of the edentata, to which belong the sloth, the armadillo, and
the like. All its predecessors are to be found also in the Pliocene strata
of South America, and only there; and mostly in gigantic, but otherwise
completely related, forms. New Zealand has no indigenous mammalia, but in
their place great cursorial birds with but rudimentary wings. Exactly the
same thing is found by geology in its tertiary and post-tertiary strata:
nowhere a mammal, but gigantic birds with rudimentary {70} wings, down to
the dinornis, which probably died out in man's time. New Holland has merely
marsupial and some monotrematous, but no placental, mammalia; even its
tertiary strata give no placental mammalia, but marsupialia, in analogy
with all living genera, herbivorous, and carnivorous. Indeed, the analogy
goes so far that the same line which through the Indian Archipelago
separates the present Australian animal and plant world from the Asiatic,
forms also the separating line for the geological zones of the Pliocene
epoch. All these are facts which render quite inevitable the idea of an
origin of the higher organic species of to-day through descent.
But still, from another side, animal geography, though it does not yet
speak for a common pedigree of the whole animal world, as the facts just
mentioned also do not, still at least speaks for a descent of related,
though at present separated, genera and species from common forefathers.
The continents of the Old and New World are so constructed that toward the
North Pole they approach one another very closely, and toward the South
Pole they withdraw from one another. Without doubt there existed in the
North, through long periods of time, a land-connection of America with Asia
and with Europe. Now, both continents have their more or less
characteristic animal world, and these characteristics are distributed over
the two halves of the globe in the following extremely remarkable way: The
fauna of the Old and the New World, in those groups of animal genera which
live only in the warmer or tropic zones or only south of the equator, and
have no associates of genera or families in the higher North, is in each
hemisphere entirely characteristic, and differs in a {71} marked way from
the fauna of the other half of the globe. For instance, the rhinoceros, the
hippopotamus, the giraffe, the antelope with undivided horns, the hedgehog,
the mole proper, are only inhabitants of the Old World, whence also the
horse originally came, the striped ones in Africa and the non-striped in
Asia; on the other hand, the lemur, the ant-eater, the armadillo, and
others, are limited to South America. The apes of the Old World have five
molar teeth on each side of the jaw, narrow noses, tails usually short and
never prehensile, and fleshy protuberances for sitting; the apes of the New
World have six molar teeth, flat noses, and long prehensile tails. And on
the contrary, where closely related species are found on both parts of the
globe, they belong only to genera of which single species live or have
lived in the far North; as, for instance, the rein-deer, still common to
the Old and the New World in this very North which once formed a bridge
between the two halves of the earth. The same is true in regard to cattle,
the deer, the cat, the dog, the hare. Similar facts can also be shown of
other animal classes. The farther the different species of these genera
withdraw from the North Pole, the greater become the differences between
the species on the one half of the globe and the analogous species of the
other. Compare on this point K. E. von Baer's "Studien aus dem Gebiete der
Naturwissenchaften, über Darwin's Lehre," ("Studies from the Realm of
Natural Science upon Darwin's Teachings"), p. 356 f. If we add, further,
the before mentioned fact, that those genera which are exclusively peculiar
to one or the other continent, have their related predecessors in the
tertiary strata of these continents, {72} the hypothesis of a separate
origin for each single species, without genealogical connection with the
anatomically and physiologically related species, becomes neither more nor
less than a scientific impossibility.
Moreover, there are several facts of _comparative anatomy_ which have long
been the joy of all zoölogists and have rewarded the toilsome labors of
detailed investigations by a delightful view over the whole realm of the
organic world, but which find a scientific explanation only in the descent
theory. They are the _homology of the organs_, and to a certain degree also
the so-called _rudimentary organs_. By homology of organs we mean the fact
that within one and the same class-group of organisms all the organs, and
especially the organs in their most solid constituents, in the skeleton,
are built after one and the same fundamental plan, and therefore are even
in their most widely separated modifications varied after this one and the
same plan. This is especially true of the vertebræ and the limbs. This
homology goes so far within one class, particularly within the class of
mammalia, that, for instance, the hands and feet of man, the hands of the
ape, the paws of the beast of prey, the hoof of the horse and of the ox,
the paws of the mole, the fins of the seal and of the whale, the
wing-membranes of the flying-squirrel, correspond to one another in their
smallest parts and ossicles, and can all be registered with the same
numbers and letters; _i.e._, they are homologous to one another even to the
minutest detail. The _ideal_ plan and connection in the organisms,
disclosed by these facts, and long ago acknowledged and admired, receives
at the same time its simple _material_ basis through the acceptance of a
common descent. {73}
A similar relation is observed in _rudimentary organs_.
Many of them, as the nipples of males, point, if not to a common descent
from a lower form, at least to a common plan of the sexes. But when the
embryo of the whale still has its teeth in the jaw, the grown up whale its
hip-bones, when the eye of man still has its winking membrane, the ear and
many portions of the skin their rudimentary muscles of motion, the end of
the vertebral column its rudimentary tail, the intestinal canal its blind
intestine; when sightless animals, living in the dark, still have their
rudimentary eyes, blind worms their shoulder-blades; when in like manner
the plants, especially in their parts of fecundation, show in great number
such rudimentary organs as are entirely useless for the functions of life,
but which are never misleading in determining their relationship with other
plants:--how simply are all these facts explained by the descent theory,
how not at all without it!
Finally, if we now mention the _history of the development of animals_, we
shall have to postpone to the next section the consideration of the most
essential facts furnished by this science; for the individual development
of animals is a process which could speak not only for a descent of the
species, but also for a descent of them through gradual development. But
where, as in the present section, we treat the descent theory apart from
the evolution theory, we have also to think of the possibility that the
species or groups of species are not originated through gradual
development, but nevertheless do originate through descent--namely, in
leaps through metamorphosis of germs or a heterogenetic generation; and for
such an idea we find confirmation in the {74} observation of the history of
development of animals, which we call _change of generation_ or
_metagenesis_.[4] By this is meant the following phenomenon: Certain
animals, as the salpa and doliolum of the order of the tunicata, as well as
certain mites and many tape-worms, produce offspring which are wholly
dissimilar to the mother stock. These offspring have the capacity of
reproducing themselves--if not by sexual means, as at the first generation,
still by the formation of sprouts; and it is only the animals originated by
the second generation (with many species, even those by the third) which
return again to the form of the first generation. The plant-lice transmit
themselves through six, seven, even ten generations by means of sprouts,
until a generation appears which lays eggs. Now it is indeed true that the
change of generation forms a circle in which the form of the last
generation always returns to that of the first, and therefore leaves the
species, as species, wholly unchanged. But it is nevertheless a process
which shows that the natural law of an identity between generator and
product, observed in other relations, is not without exception; and if we
once have reason to suppose that the generation of new species took place
in past periods of the globe, but has ceased in the present, such processes
in the single period open to our direct observation--namely, the present
(in which, however, according to our knowledge, the species remain
constant)--are {75} nevertheless hints worthy of notice. For they refer us
to ways in which in those former times, when certainly new species did
originate, this formation of species might possibly have taken place.
This consideration leads us to treat of the main objection raised to every
descent theory: namely, that never yet has the origin of one species from
another been observed, but that, on the contrary, _all species_--so far as
our experience goes, stretching over thousands of years--_remain constant_.
We will give no weight to the fact that the constancy of species seems by
no means to be absolutely without exception; for on the whole, they
certainly remain constant. The only example which goes to prove such an
evolution of species as taking place to-day--viz: the natural history of
sponges--seems not to have this bearing. The transitions of form, proven by
O. Schmidt in the siliceous sponges and by Häckel in the chalk-sponges,
seem to show, not the genetic coming forth of a new species out of another,
and especially not the evolution of a higher species out of a lower, but
rather the uncertainty of the idea of species in general and the
worthlessness of the skeleton-forms, for this idea, in such low
organizations as the sponges. But that objection already loses its chief
force from the consideration that we have not only never observed the
origin of one species from another, but never even the origin of a species
itself; and that nevertheless all species have successively originated in
time. If we, therefore, are not able to observe directly their origination,
we have a right to make all possible attempts at approaching the knowledge
of it in an indirect way. But we see this objection invalidated by still
another {76} fact. From all observations, it seems to be evident that those
agencies which originated the species in general have ceased since man
appeared. Now this fact is inconvenient for all those who, on metaphysical
grounds, reject aim and purpose in the world and accept an aimless motion
in the universe, a circle in which only identical powers are ever active to
all eternity. From this standpoint, the scientists cannot, except by very
artificial hypotheses, escape the conclusion that, if new species once
originated through descent, new species ought still to originate through
descent. In like manner, it is true, they are also obliged to accept the
other conclusion: that if new species once originated through primitive
generation, new species ought still to originate through primitive
generation. On the other hand, those scientists who recognize aims in the
world for which the world and each part of it is destined, and which are
attained in the world through the processes of coming into existence, have
to expect in advance that the organic kingdoms are also planned with
reference to those aims. They naturally see the aim of the origin of
species attained, where in the organic world beings appear who combine with
the highest physical organization a self-conscious and responsible
spiritual life, and who are capable of conceiving the ideal, even the idea
of God. For, with the appearance of these beings, there enter upon the
theatre of the world beings who go beyond the value of a purely physical
organism and of a purely somato-psychical life, and in like manner
represent again a higher order of beings; just as the first appearance of
organic life on earth once introduced a new and higher stage of {77}
existence in contrast to the inorganic world. Scientists who take this
standpoint can readily adopt the fact that we do not now observe the
origination of new species; for it is in full harmony with their
metaphysical doctrines, without the same being on that account essentially
dependent upon the confirmation or rejection of the hypothesis of the
present constancy of species. With this very fact, the maxim that if new
species once originated through descent, new species must still originate
through descent, has lost for them its truth, and therefore its power of
demonstration. So we see even here, while in the midst of the discussion of
a purely scientific problem, in what close correlation metaphysics and
natural science stand, and moreover--since the metaphysical view is most
closely connected with the religious--in what close relationship religion
and natural science stand. At the same time we also see how little the
metaphysical interest, and much more how little the religious interest, has
reason to avoid the investigation of facts in nature.
§ 4. _The Theory of Evolution--Archæology, Ethnography, Philology._
The evolution theory teaches that the species have developed themselves one
from another in gradual transitions, each of which was as small as the
individual differences still observed to-day among the individuals of the
same species. It is not without support, especially in the _history of the
development of plants and animals_.
Each organic being becomes what it is by means of organic development. Each
plant, even the highest organized, begins in its seed-germ with a simple
cell, {78} and is differentiated in constant development up to the fully
perfected individual. Each animal, even the most highly organized (man
included), begins the course of its existence as an egg; and each egg has
no greater value of form than that of a single cell. This egg-cell is
differentiated, after fecundation, in gradual and imperceptible
transitions, farther and farther, higher and higher, until the individual
has reached its perfect organization. No organ, no function of the body, no
power or function of the soul or of the mind, appears suddenly, but all in
gradual development. Since we see all individuals thus originating by means
of gradual development, the possibility lies very near that the different
organic formations of all the organic kingdoms could also have been
originated by the same means.
In still another direction does the history of the development of single
plants and animals make this possibility plausible to us. In the animal
world, and partly also in the plant world, the single individuals of higher
species in their embryonic development pass through states of development,
in the former stages of which not only the individuals of the most
different species look confusingly similar to one another, but also the
embryos in their organization remind us of the perfected state of much
lower classes of beings. In order to give a clear idea of the first
mentioned facts, Häckel, for instance, in his "Natural History of Creation"
and in his "Anthropogeny," represents by engravings the embryos of
different vertebrates and also of man; representations which--although,
according to the judgment of competent scientists, unfortunately not exact,
but modified, after the manner of stencil plates, in favor of {79} greater
similarity--yet make it quite clear that the similarity of the different
embryos must be very great. We see, for instance, on one table the embryos
of a fish, a salamander, a turtle, a fowl; on a second, those of a pig, an
ox, a rabbit, a man; on a third, those of a turtle, a fowl, a man; and we
find the similarity really great. Examples of the second fact--that
individuals of higher classes or orders in former states of their embryonic
development represent an organization which corresponds to the full-grown
individuals of the lower classes--are: the tail of the human embryo, the
gill-arches of the embryos of reptilia, of birds, of mammalia, and of man.
Now Häckel here takes up again an idea first suggested by Fritz Müller, and
derives from these observations the "biogenetic maxim," as he calls it:
"The history of the germ is an epitome of the history of the descent; or,
in other words, ontogeny (the history of the germs or the individuals) is a
recapitulation of phylogeny (the history of the tribe); or, somewhat more
explicitly: that the series of forms through which the individual organism
passes during its progress from the egg-cell to its fully developed state,
is a brief, compressed reproduction of the long series of forms through
which the animal ancestors of that organism (or the ancestral forms of its
species) have passed from the earliest periods of so-called organic
creation down to the present time." In his latest publication, "Ziele und
Wege der heutigen Entwicklungsgeschichte," ("Aims and Methods of the
Present History of Evolution"), he admits into the formulation of his
biogenetic maxim also the consideration of those phenomena in the
ontogenetic development which are no recapitulation of the history {80} of
the stem, but originated by adapting the embryo to its surroundings. In the
description and explanation of this theory, he uses a term which throws
upon nature a peculiar reproach, never before made, namely: cenogeny, or
history of falsifications, in contrast to palingeny, or history of
abridgments. This amended formula now reads: The development of germs is an
abridgment of the development of stems, and is the more complete according
as the development of the abridgment is continued by inheritance, the less
complete according as the development of the false is introduced by
adaptation.
Now, we ask: Is this biogenetic maxim correct? and moreover, from the fact
of the organic individuals originating through development, are we entitled
to draw the conclusion that even the species must have originated through
development? To this question we can no longer get an answer from the
life-processes of living organisms; for we have already mentioned the fact
that, according to the present state of our knowledge, we can no longer
observe the origination of a new species. Moreover, the embryonic states of
development show also, in all their similarity, even in the very first
stages, and with especial distinctness in these first stages, many
differences between the single species; and this is true especially of
those species which, according to the followers of this so-called
biogenetic maxim, should lie in the same stem-line,--so that the direct
scientific value of the embryological results to the palæontological
investigation, or of the latter to the former, is so far very slight. Such
a problem, however, as the one contained in that biogenetic maxim, which
only gives to investigators the _direction_ in which possibly an {81}
interesting and profitable path can be opened, does not at all deserve the
name of a "_law_." K. E. von Baer, the founder of the whole present science
of the history of development, has certainly a most competent judgment of
the correctness of this so-called biogenetic maxim; and he convincingly
shows, in his essay on "Darwin's Doctrine," that the embryos never
represent a former animalic form, but that their development follows the
principle of representing first the common characteristics of the class,
then those of the order, etc., until finally the individual characteristics
appear in the formation. Those who wish more information about embryology
can find it in Heinrich Rathke's "Entwicklungsgeschichte der Wirbelthiere"
("History of the Development of Vertebrates"), edited by A. Kölliker,
Leipzig, Engelmann, 1861; and those who wish to inform themselves as to the
influence of the ontogenetic results of the solution of the phylogenetic
problems, will find, besides the before-mentioned work of Wigand, rich and
clearly elaborated material in the publication of Wilhelm His--"Unsere
Körperform und das physiologische Problem ihrer Entstehung, Briefe an einen
befreundeten Naturforscher" ("The Form of our Body and the Physiological
Problem of its Origin; Letters to an Associate Scientist"), Leipzig, Vogel,
1875. The latter writer, although he advocates the descent theory, rejects
the hasty assertions of Häckel with direct and convincing arguments.
Thus embryology, having from the simple fact of an origin of single plants
and animals through descent at least confirmed the idea of the
_possibility_ of an origin also of species through development, forsakes us
in the {82} inquiry as to the _reality_ of such a genealogy of development,
and refers us to other sciences.
Such a science, from which we certainly are entitled to expect a decided
answer, is _geology_. For if the evolution theory is right, those periods
of the history of our globe in which new species originated--namely, the
periods of geology--_must_ show us also the _forms of transition_ between
the different species. And, indeed, geology gives us an answer; but it
reads contradictorily: It says yes, and it says no.
Geology does show us forms of transition, and, indeed, most frequently in
the lower classes of animals. Who that has once studied petrifactions, does
not know the mass of forms of the terebratulæ, the belemnites, and the
ammonites, in the Jura formation? Würtemberger has brought light into the
perplexing division of species of the ammonites by simply showing their
temporary and systematic transitions into one another. In the fresh water
chalk formation of Steinheim, near Heidenheim, in Würtemberg, scientists
have found, on the same place, in an uninterrupted series of strata, the
snail valvata or paludina multiformis in all imaginable transitions--from
the flat winding, showing the form of a chess-board, up to the sharp form
of a tower. And it was not, as Hilgendorf thought, in a series which can be
traced in the strata according to time, but, as Sandberger says, in quite a
varied mixture, yet in all imaginable modifications. But even among the
higher and the highest classes of animals, we can trace the transitions.
The flying sauria, if not in their organs of flying, which remind us more
of the bat, at least in head, neck, and toes, are closely connected with
the {83} birds--the oldest birds of the Jura and chalk formations, with
their tail-spines similar to the reptilia and their teeth in the beak to
the sauria. The tertiary formations especially show the primitive history
of many vertebrates in very instructive forms of transitions--which, for
instance, Rütimeyer, a scientist who is very cautious in his conclusions,
very distinctly traced to the horse, to the ruminating animals, and lately
also to the turtles. Still more in detail, W. Kowalewsky has lately shown
us the primitive history of the horse, and Leidy and Marsh have further
completed it by the addition of American forms, the former having at the
same time described the forms which have led to the tapir.
But to such facts there are, on the other hand, experiences directly
contradictory. Many lower and higher forms of animals and plants appear in
the geological strata, so far as they have been explored, in a wholly
independent way. We have mentioned, in the foregoing section, that the main
types of the invertebrates appear somewhat contemporaneously and without
any traceable intermediate form. The trilobites, a quite highly organized
order of crustacea, appear in the strata of the silurian epoch almost
suddenly, in very many and very distinctly marked species. The uncertainty
of our knowledge shows itself most clearly when we ask for the geneologic
relationship of the vertebrates. In Chap. II, § 1 and § 2 we have already
referred to the value which Darwin, and more especially Häckel, lays on the
relationship of the larva of the ascidia to the lancelet fish. Now the
important testimony of K. E. von Baer, in his "Mémoires de l'Académie de
St. Pétersbourg," Ser. vii, Vol. 19, No. 2, tells us that the
nerve-ganglion {84} of the ascidia lies on the side of the stomach, and on
that account can not be homologous with the spine of the vertebrates, but
that the cord in the larva of the ascidia is nothing more than a support
for the tail in swimming, which afterwards disappears, as with many other
larvæ. As to the course of reasoning in reaching these genealogical
conclusions, he says: "The hypothesis is indeed flexible. According to
common reasoning, that which shows itself early in the development is an
inheritance of the first progenitors. Therefore the ascidæ ought to descend
from the vertebrates, and not the reverse. But it was necessary to show the
descent of the vertebrates from the lower forms. In order to respond to
such a necessity, men sometimes reverse their conclusions. Although
favorably disposed to the doctrine of the transmutation of the animalic
forms, I want a complete proof before I can believe in a transformation of
the vertebrate type into that of the mollusca." Moreover, the zoölogists
Semper and Dohrn find in the embryonic development of the sharks, the
scates, and other cartilaginous fishes, organs which would bring them
rather into a nearer relationship with the ringed worms than with the
crustacea. When, on the other hand, we look around in palæontology, the
oldest fossil fishes remind us neither of the crustacea nor of the ringed
worms, but of the crabs: a class of animals which lies entirely outside of
Häckel's stem-line of vertebrates. Also the first appearance of mammalia
does not show transitions. Thus far we have not found in the geological
strata any vestiges of the half-apes, which, according to the hypothesis of
the evolutionists, as a common stem-line for the lines of ape and man
development, once played such an {85} important _rôle_, and which have
quite numerous representatives.
But the answer which geology gives to our questions as to the probable
confirmation of the evolution theory, naturally becomes most interesting
where the _origin of man_ is treated of. Our attention is, therefore,
especially directed to the most recent formations of the globe which show
us the oldest remains of man. The most instructive are those parts of the
skeleton which allow us to draw the most convincing conclusions as to the
degree of mental development of an individual, namely: the parts of the
skull. Although human bones seem to have been less easily preserved than
those of animals, and are, comparatively speaking, very scarce, especially
more so than prehistoric implements, still there are not wanting such
remains, which go back far beyond historical time. The oldest known skull
is the celebrated one of the Neander cave near Düsseldorf, with its large
vault of the forehead, and its low height. Although Virchow finds on it
evidences of rachitis in youth and of gout in old age, as well as of
injuries, it nevertheless can not have been changed in its _fundamental
form_ by any sickness, even according to Virchow. This very skull now
indisputably shows a still lower formation, which, although quite
essentially different from the type of the ape, stands nearer to it than is
the case with the skulls of men in later times. Of a later date, and of a
correspondingly higher form, are the skull of Engis, of Cannstatt, the
skulls of the Belgian caves (especially Chauvaux), of France, and of
Gibraltar. According to the weighty authority of Schaaffhausen (note his
opening address at the Wiesbaden Congress of the {86} Anthropological
Society, 1873), the skulls and the remaining parts of the skeleton show
more indications of a lower formation the older they are. He especially
calls attention to a certain bone of the roof of the skull--the _Os
interparietale_ or the so-called _Os Incæ_--which has only recently been
recognized as a characteristic of a lower formation of skulls, standing
nearer to that of animals. As late as the summer of 1873, two human
skeletons were found at Coblenz in a volcanic sand, of which Schaaffhausen
says: "No less than eight anatomic marks of a lower formation, which
probably have not heretofore been found together, indicate the great age of
these remains." With all these traces of a difference between the former
and the present state of the physical condition of man, the differences
between the type of man and that of the animal are still great enough to
leave wide open the possibility of the origin of man through some other
means than that of gradual development. On the other hand, it is more or
less in favor of the evolution idea, that so far such old remains of man
have been found in places which certainly can not have been the cradle of
mankind, and that those parts of the earth which we would naturally suppose
to be the first dwelling place of the earliest human genera have been
little or not at all investigated. And also the hypothesis of Häckel, that
the cradle of mankind was a land between Africa and Asia, now sunk in the
sea, and called Lemuria, can be neither proved nor denied. Such vague
possibilities have indeed not the least scientific value.
In considering these contradictory results of geological investigation, we
dare not overlook three points: First, our knowledge of the crust of the
globe is still {87} very fragmentary, and does not yet extend over the
whole globe. Further, it lies in the nature of the case that the strata in
mountain formations can only give a very incomplete picture of the whole
variety of the real organic life which may have populated the earth and the
sea. What a poor picture of the present plant and animal life would be
offered, for instance, by the soil of our continents, the slime, sand, and
pebbles of our coasts and of the bottoms of our lakes and seas, if we had
to construct from them alone the fauna and flora of the present! A third,
but purely hypothetical, consideration is rendered of importance
particularly by Darwin and Häckel; namely, that the forms of transition
without doubt existed for a shorter period than those forms whose
organization has established itself in fully developed species.
Thus far we have directed our attention to inquiring how the organic
individuals were originated--and have throughout observed a successive
development; next, we have questioned geology--and here also have observed
a progress in the appearance of the species, but have received at the same
time contradictory answers to the question whether this progress presents
itself as a gradual development of one species from another or as a sudden
appearance. So the reasons for and against the evolution theory almost
balance one another; and it is not improbable that the hypothesis of an
origin of species through development will have to share its authority with
the hypothesis of a descent of species through heterogenetic generation, as
well as with the hypothesis of a primitive generation of lower organisms,
still repeating itself at a later time. Thus for the origination of {88}
groups lying nearer together, we have the evolution theory; for the other
groups, and especially for the origination of types where no transitions to
other types can be traced, the theory of the heterogenetic or primitive
generation recommends itself; and both theories thus far are of a purely
hypothetical nature.
But there is still a third realm, which is just as open to our observation
as the history of the development of organisms and as geology, and of which
we can also ask, whether it does not open for us an indirect way to the
knowledge of the origin of species, and especially of man--a knowledge
which we can no longer approach in the direct way of observation. This
realm is _natural history_ and the _history of the development of the human
race_. For mankind also is engaged in a process of development, and its
present members do not stand on the same height. Now the question is, to
what beginning can we trace backward the development of mankind, and to
what succeeding stages of development from this present condition? And do
we find in these earliest periods, and on these lowest stages, points that
are connected with still earlier conditions and organizations, and
especially points which could genealogically join together mankind and the
animal kingdom? Three sciences, still young, favorite children of the
present generation, participate in investigating this realm, namely,
_archæology_, _comparative ethnology_, and _comparative philology_.
_Archæology_ leads us back to far-off times. It is a fact that,
chronologically speaking, man lived in the glacial period--according to
French scientists, even before it; and that, palæontologically speaking,
man and {89} mammoth lived at the same time, and, according to a discovery
made some thirty years ago at Denise in Middle France, probably even man
and another older and defunct form of pachydermata, the elephas
meridionalis, in North America man and the mastodon. The reader may compare
the discoveries regarding the age of mankind, as they are described most
recently by Sir Charles Lyell in his work upon this subject, in the
publications of the Anthropological Congress at Brussels in the year 1873,
and in those of the fourth General Assembly of the German Society for
Anthropology, Ethnology and Primitive History, at Wiesbaden, in the year
1873.
Now, to be sure, from the oldest human _tools_ and _utensils_ that are
found, we can expect still less than from the oldest human bones that they
will throw direct light upon the answer to the question of the _origin_ of
man. For where man not only uses tools, but _manufactures_ the same for
use, a wide breach already exists between man and animal. Manufactured
articles, therefore, can only throw some light on the history of the
development of the already existing human race. And even this light is less
clear than we perhaps expected in view of the first interesting
prehistorical discoveries. It is true, all these discoveries show us an
ascent from the simplest and roughest forms to the more perfect; from the
split but unpolished stone to the polished, and from stone to bronze and
iron. But a progress of the human races in manufacturing and using
articles, from the simple and rough form to the more artificial, lies so
much in the nature of the case, and is so taken for granted with every
conception of the origin of man, even with that contradictory to Darwinism,
that from this simplicity of {90} the earliest tools we can not at all
conclude that there was a condition of mankind lying near that of animals;
and especially we can draw only general and uncertain conclusions as to
that which makes man _man_, as to the spiritual and moral qualities of
those prehistoric men. Moreover, in discoveries belonging to the very
oldest, we come upon drawings and engravings from which we recognize the
man of those primitive times as a creature whose life was not entirely
taken up in the animalic struggle for existence, but was already adorned
with those ideal pursuits and enjoyments which we are accustomed to ascribe
to the height of civilization. Examine, for instance, the drawing of a
mammoth on a mammoth tooth of Dordogne, which the French scientists Lartet
and Christy have reprinted in their Reliquiæ Aquitanicæ (1868), and which
Sir Charles Lyell has copied in his "Age of the Human Race." How much
spirit and life in this primitive work of art! Or read what Fraas, in the
"Journal of the German Society for Anthropology," March, 1874, reports
about the picture of a grazing reindeer, engraved on a knife handle made of
the horns of a reindeer, which was lately found in the cave of Thayngen
near Schaffhausen, and which surpasses in beauty all rough drawings thus
far found. The whole bearing of the animal--the muscles of the legs and the
head, the form of the many-branched antlers, with the wide-spread eyes, the
representation of the hair upon the body and under-jaw--all disclose a real
artist among those savages.
This is also to be taken into consideration: that those men, whose traces
we find, could possibly have been the descendants of more noble
predecessors, driven {91} off and degenerated, just as well as they could
have been representatives of the whole former condition of culture of
mankind. In England, where the questions of the first condition of culture
of mankind are very warmly discussed, the Duke of Argyll particularly, in
his "Primeval Man," advocates these views, and very forcibly calls
attention to the fact that thus far the places of the discovery of the
earliest traces of man undoubtedly lie very far from the original home of
the human race; while Sir John Lubbock, in his "Origin of Civilization" and
in his "Prehistoric Times," and also Tylor in his "Beginning of Culture"
and in his "Early History of Mankind," take the opposite view of a progress
of mankind from the most uncultivated beginnings.
Archæology, as a whole, seems to do no more than admit that its results can
be incorporated into the theory of an origin of the human race through
gradual development, _if_ this theory can be shown to be correct in some
other way, and that its results can just as well be brought into harmony
with a contradictory theory.
_Comparative ethnology_ gives us quite a similar result. It is true, there
are races of mankind in the lowest grades of human existence. It is well
known how Darwin, in his voyage on board the "Beagle," got one of his first
vivid impressions of the possibility of an evolution of man from the animal
world, by seeing the inhabitants of Tierra del Fuego; and it is remarkable
that the arms, tools, and furniture, used by the lowest savages, are very
similar to the earliest remains of civilized races found on earth. The
conclusion lies extremely near, that the savages simply remained in earlier
stages of human culture; and an ethnographic picture of mankind {92} at
present would in a similar way give an approximately correct view of its
former development, as the natural zoölogical and botanical system of the
present fauna and flora must give us at the same time the key to their
pedigree; supposing the Darwinian theory to be correct.
If it were so, ethnology would be an altogether inestimable help for the
exploration of the descent and development of the human race. For the
extremely few and rare fossil remains of man--which, moreover, do not give
us any answer to the most important questions in regard to the mental and
moral quality of the primitive man--would be rendered complete by living
examples of the kind, which remained at the old stages of development.
But much is still wanting, before the followers of an evolution theory dare
to use ethnology directly as a primitive history of the development of
mankind, prepared and preserved for them. Especially the before-mentioned
objection of the Duke of Argyll--that the lowest savages of our time can
just as well be depraved as be men who remained stationary in the process
of development--has here increased weight. Moreover, even with the savages
of to-day, a rude state of their tools and a low condition of their mental
and moral life are not so nearly parallel as to allow unrestricted
conclusions to be drawn. Finally, we still know too little about the state
of culture of the savages; and the deeper and higher the intellectual and
ethical possessions of mankind are, the presence of which among the savages
is in question, the more uncertain is our knowledge.
This is especially true of the most important question in this
connection--the question as to the existence {93} or absence of an idea of
God, and the different stages of development of religious ideas. While some
assume as an established fact, that there are savage tribes without any
idea of God or any religion, and even give the names of these tribes,
especially of some from the interior of South America; while Sir John
Lubbock systematically enumerates seven stages of religious development,
from atheism to the connection of religious with moral conceptions, and
lets each single race run through these stages in an identical series until
it either remains on one of the seven stages or arrives at the highest:
yet, on the contrary, other equally trustworthy scientists assert that
there is not a single human race without some idea of religion and of a
God--indeed, not a single race without a monotheistic presentiment--and
that all heathenism, down to its most degenerate stages, consists not so
much in a non-recognition of a God as in ignoring him. They call especial
attention to the difficulty of getting acquainted with the ideas of a
savage tribe without living with it through many years and being intimate
with its language and customs, and especially without enjoying the
unrestricted confidence of the tribe. Mutual misunderstandings, a
suspicious reserve, evasive and untrue answers to questions, are entirely
unavoidable without those conditions. At any rate, the fact deserves
attention, that those who have been longest and most active among savages,
and who enjoyed their confidence to the fullest extent, all reached this
result: they found them not only not without religion, but also not without
a presentiment of the monotheistic idea of God. Livingstone, for instance,
expressed this idea decidedly of all the African tribes {94} with which he
became acquainted; and Jellinghaus gives the same evidence in regard to the
Kols in South Asia.
The _anatomic_ results of ethnology are more favorable to the descent
theory, although they too lead no farther than to the conclusion that the
skull-forms of the lowest tribes represent a lower stage of formation than
those of the higher, and that these lower skull-forms are relatively nearer
to the ape-form than the higher, but that they are still separated from it
by a wide interval.
It appears, then, that even ethnology does not lead us essentially nearer
the solution of the question than archæology and geological anthropology.
The relatively strongest support to the evolution theory is given by
_comparative philology_; and since language is the most important and most
decisive of all the distinctive characteristics which separate man and
animal[5], this science deserves especial consideration.
In the realm of the natural sciences, the enormous progress of palæontology
on the one hand and of systematic zoölogy and botany on the other took
place step by step together, and thus prepared the way for Darwin's
idea--which, from the rich material of analytical investigations, only
tries to draw the simple synthesis, and to show at the same time in the
zoölogical and botanical _system_ a representation of the zoölogical and
botanical _history of development_. In quite an analogous way, a process
took place in the linguistic realm which in independent investigations
prepared the way for Darwinism, and now, since Darwin's theory has sought
{95} acknowledgment in the realm of natural history, brings again Darwin's
ideas to the support of philology.
Linguistic and ethnographic investigations, especially the linguistic works
of the missionaries, long ago resulted in gathering rich material from the
storehouse of the language of races now living, and the latest works in the
realm of historical, etymological, and comparative philology had traced the
branches and twigs of the better known languages to stems and roots lying
far back. The result of the comparison soon became the same as in the realm
of the organic world: what presented itself in the system of the living
languages as a lower form, seemed to represent itself as the older and more
original form also in the history of languages. Therefore, all the
prominent linguistic investigators found themselves more and more urged to
accept a theory which declares language, this entirely specific
characteristic of man, to be subject to the same laws of development from
the simpler and most simple forms as the world of the organic. Long ago so
celebrated a man as Jacob Grimm,--"Ueber den Ursprung der Sprache" ("The
Origin of Language"), Berlin, Dümmler--following the footsteps of Wilhelm
von Humboldt, had established a theory, according to which language is "not
created, but produced by the liberty of the human will;" and judging from
many of his Darwinistic utterances concerning the origin and development of
language, he had traced its development in such a way as to arrive at the
conclusion that artless simplicity in the unfolding of the senses is the
first period of its appearance.
The scientists divide all the languages of the earth into three great
groups: first, the monosyllabic, {96} isolating, radical, or asynthetic
languages; second, the agglutinant, terminational, or polysynthetic
languages; third, the inflectional languages. They are of the opinion that
even the languages of highest rank--the inflectional--very probably took a
starting-point from the asynthetic languages, and a course of development
through the agglutinants, and that in like manner the agglutinants have
behind them an asynthetic period. Thus they trace all the languages back to
certain _roots_, which are more or less common to the different groups of
languages.
To the question that now arises--_How did these roots originate?_--the
linguists give us three different answers. The onomatopoetic theory, called
by Max Müller the Wow-Wow Theory, traces them to imitations of the sound
(W. Bleek, G. Curtius, Schleicher, Wedgewood, Farrar); the interjectional
theory, called by Max Müller the Pooh-Pooh, or Pah-Pah Theory, traces them
to expressions of the senses (Condillac); a third theory declares the roots
to be phonetic types (Max Müller, Lazar Geiger, Heyse, Steinthal); while it
is still an open question, whether the attempts at explanation of these
types must here come to a stand-still for the present, as Max Müller
thinks, or whether, according to Lazar Geiger, we can trace the first
root-expressions especially to impressions of light and color.
The reasons from which Max Müller, in his "Lectures on the Science of
Languages" (Vol. I, Lect. IX), rejects the first two theories and proves
the third, are quite convincing. Even if, in a purely hypothetical way, a
language could be thought of _in abstracto_, the roots of which only
consist in imitations of sounds or interjections, still in the _really
existing_ languages, {97} so far as we can trace back and uncover their
roots, the roots imitating sounds and the interjectional roots form only a
small and entirely isolated minority, which neither shares in, nor is
capable of development; they stand like "dead sticks in a live hedge." By
far the greater number of roots, and all which are capable of development,
express abstractions from visible objects, conditions and activities, and
therefore presume a human intelligence, reflecting with self-consciousness,
which formed and used the roots.
Now Max Müller sees, back of this period, still open to science, in which
the root-elements of the human languages were fixed, a long period of
exuberant and unhindered growth of the elements of language, in which the
roots were separated from the multitude of nascent tones by elimination or
natural selection in the struggle for existence. In this realm, which is no
longer open to investigation, the naturalistic and the linguistic friends
of the evolution theory are now in entire accord. Wilhelm Bleek, in his
small, but very noteworthy essay, "Ueber den Ursprung der Sprache" ("Origin
of Language"), Weimar, Böhlau, 1868, p. 11, uses this ingenious figure:
what the animal world possesses analogous to language, takes about the same
position as, in the art of printing, the block-print does in relation to
printing with movable types. On page 12, he sees in the communication of
the emotions among animals the sources from which under favorable
conditions (in consequence of which the separation of language into
articulated parts became possible) human language might have originated.
This idea, which is closely joined to the interjectional theory, Darwin
meets {98} with a related idea, depending upon the onomatopoetical theory,
when he says, in his "Descent of Man": "Since monkeys certainly understand
much that is said to them by man, and when wild, utter signal-cries of
danger to their fellows, may not some unusually wise ape-like animal have
imitated the growl of a beast of prey, and thus told his fellow-monkeys the
nature of the expected danger? This would have been a first step in the
formation of language."
But philology, from the point where it goes farther back in search of the
roots of language, leaves the safe ground of knowledge and commits itself
to the fluctuating ocean of conjectures; and since also the scientific
evolution theory has only a hypothetical value, the support of a hypothesis
in the one science by a hypothesis in the other naturally adds no weight to
its probability, either for the one or the other. Besides, we must not
overlook the fact that the very point in the history of the development of
languages on which the investigation, as it looks backwards, must at
present pause--namely, the existence of linguistic roots--presumes a
faculty of abstraction which can not be thought of without
self-consciousness.
Therefore archæology, comparative ethnography, and comparative philology,
show us quite clearly a _development_, but not an _origin_ of mankind
through development. Yet they do show an already existing development of
mankind; for all three sciences lead back to starting-points, where mankind
already existed with all the essential attributes of mankind, and leave us
without answer to our questions as to the conditions lying still farther
back. Their results we can {99} without difficulty harmonize with a theory
which supposes mankind to have originated by evolution, provided such a
theory could be confirmed from another side; but they agree just as well
with a contrary theory, which excludes the origin of mankind by gradual
development.
Taking, thus, everything into consideration, we come to the conclusion that
the evolution theory, like the descent theory, is so far only a
hypothesis--and, indeed, a hypothesis which as such has a much more
problematical character than the descent theory. For while in regard to the
latter we had to say that we have either this explanation or none of the
origin of the higher species, with the evolution theory there is not even
room for this alternative. For even in case of its failure, a descent of
one species from another through heterogenetic generation is certainly very
possible. Besides, it is not only possible, but even probable, that both
theories--that of heterogenetic generation and that of gradual
development--may have to share with one another in the explanation of the
origin of species; and even that, especially for the lowest species and for
the beginnings of the main types, primitive generation also has its share
in the establishment of the paternity.
The evolution theory could only pass beyond the rank of a hypothesis, if we
should succeed in showing the impelling forces of such an origin of species
through development. Such an attempt can be made in two ways--the
metaphysical and the scientific-empirical. The first, the metaphysical,
although it may be justified in its general principles, will always, from
the point at which it attempts to approach the concrete questions as {100}
to the origin of single species, expose itself to the fate of being _a
priori_ rejected by science as unjustified, and of being _a posteriori_
confuted by facts--a fate which it has richly and clearly experienced in
the first half of our century. But the discussion of the metaphysical way
does not belong to the present purely scientific part of our investigation;
it will, however, be shortly taken up again in Book II. The other way, the
scientific-empirical, will have to be looked upon as correct when it can
show the impelling forces of development in such powers and laws as are
either still active to-day or at least have their points of connection in
powers and laws active to-day. Such an attempt is the selection theory. We
have already in Chap. II, § 1 and 2, given an outline of this theory, and
have only yet to discuss its present state of tenability.
§ 3. _The Theory of Selection._
The selection theory also is not entirely without support in the realm of
observed facts. How simply it explains the fixedness of the differences of
closely related species arising from their geographical and climatical
home! how simply the similarity of the color of many animals from the color
of their abode, through which they have protection against persecution! how
simply the so-called _mimicry_--_i.e._, the similarity of certain species
in form and color with form and color of entirely different species in the
midst of which they live, a similarity which often gives them protection
against persecution! The best known examples of this, in our regions, are
the spinning caterpillars, which in a state of rest look strikingly like a
twig of a tree or a shrub on which {101} they live. In other regions there
is a multitude of the most striking freaks of nature of this kind--for
instance, butterflies and other insects, which at rest look like the leaves
of plants under which they live; butterflies living among other butterflies
which, by an offensive odor, are protected against persecution, and
although they are themselves a favorite food for birds, carrying the form
and color of that badly-smelling family of butterflies. We can also add the
orchideæ, and their resemblance to bees, flies, butterflies, spiders, etc.
A. R. Wallace and Darwin themselves recur often to these striking
appearances.
But herewith we have mentioned nearly every support which the selection
theory has on the ground of observed facts. More numerous and more weighty
are the objections to it. First of all, we have to state that the selection
theory no longer enjoys that protection which the descent and evolution
theories can justly claim, against the main objection, mentioned in Chap.
III, § 1, to all the ideas of descent, development and selection. That main
objection is the permanence of species, observed through thousands of
years; and the defense with which the descent and evolution theories
successfully weaken it, is the statement of the fact that, since man
appeared, no new species has originated, and that therefore the principle
of the generation of species seems to have come to a stand-still. Now this
fact is no longer in favor of the selection theory, but directly repugnant
to it. For the selection theory expressly declares the origin of species
through agencies that are all active still, and, therefore, if they really
suffice to explain the origin of species, would not only have to generate
new species, {102} but also to develop _all_ the existing species. All
those circumstances which, according to the selection theory, have led to
change of species, are just as active to-day as they are supposed to have
been from the beginning of organic life; and the effect which we observe is
not change but permanence of species. The individuals still have individual
qualities; they still have the tendency to inherit, in addition to the
qualities of the species, those of the individual; the individuals still
change their abode, and therewith also their conditions of life; a natural
selection still takes place in the struggle for existence; and what is the
result? From an observation stretching over thousands of years, we find
nowhere an effect of natural selection going farther than alterations in
growth and color and purely external changes in form. All the dispositions
of organisms and their reciprocal action aim not at increasing the
individual differences, but at reducing them to the average character of
the species. When the species change their abode or their conditions of
life, they either perish or remain constant; at least, with the exception
of the slight modifications before mentioned. Even those alterations which
artificial breeding produces, have a tendency to return to the original
species: as soon as cultivated plants and domestic animals are left to
themselves, they run wild, _i.e._, they reassume their original qualities.
Even the bastard-formations either cease to be fertile, or, remaining
fertile, finally return to one or the other stem-form of the originally
crossed species. Nor can we oppose to these facts the consideration that
the period of time during which mankind has observed the organisms is too
short. For the permanence of very many {103} species can be traced through
thousands of years, and the shortness of the period of our observations is
amply counterbalanced on the one hand by the multitude of species from all
parts of the organic systems which come under our notice, on the other by
the immense alterations in the conditions of existence to which man submits
plants and animals. How great, for instance, are the alterations in the
conditions of existence which tropical plants undergo in our hot-houses and
gardens! And the only alteration they show is that they are stunted and
only bear blossoms with difficulty and fruits with still greater
difficulty.[6] Now, if the ever-active selection principle does not produce
in thousands of years even minimum alterations which can be observed,
science certainly is justified in doubting for the present the asserted
effect of that principle.
Thus not only are the _facts_ directly opposed to the autocracy of the
selection principle; but _logic_ is also none the less so. For, under the
most favorable circumstances, selection would only explain the
_preservation_ and perhaps also the _increase_ of useful qualities and
organs, _if_ the same are already in existence and have shown themselves
useful to the individual; but would not explain their _origination_. This
would rather most emphatically be left to _chance_. According to the strict
selection theory, it would be _pure chance_ that among the thousands and
thousands of individual qualities of the individuals of a species, such
qualities are always existing as offer advantages to the individual in his
struggle for existence. And it would be a second series of chances, which
from generation to generation would {104} have to coincide with the first,
that among the individual qualities advantageous to the individual and
making it victorious in the struggle for existence, there should be found
always just those qualities which develop the species and raise it to a
higher rank and order in the zoölogical and botanical systems. But the
total of improbabilities which would have to be overcome continually in
this theatre of chance, would in the course of generations necessarily
amount to infinity. Thus, in the very beginning, insuperable doubts arise
as to how we can explain from two causes the world of organisms which is so
richly, beautifully, and systematically arranged. The first of these causes
is the inclination to individual alteration, inherited indeed in the
organisms, but in itself absolutely indifferent, for the systematical idea
in the framework of the organic systems and for the progressive element in
the development. The other is the struggle for existence and natural
selection, which approaches the organisms purely from without like
individual variability, must as a whole appear a necessity, but in each
single case in the concrete mixture of coinciding circumstances, would seem
a work of chance for the individual which is to be changed.
Moreover, it is a demonstrable impossibility to explain the origin of just
those organs and members in the structure of organisms which are
systematically the most significant and functionally the most important, by
means of natural selection. It is true that many of these organs and
members, in their perfected state, offer to the organism an immense
advantage over lower organisms; but if they had been originated through
gradual development, they would have been in their first {105} beginnings
and earlier stages of development at least quite indifferent, often
directly obstructive to the individual in its struggle for existence, and
therefore would have been called into existence and developed by agencies
which had an effect directly counteracting natural selection. How high, for
instance, stand the vertebrates above the invertebrates! Yet how could the
first deviation from the ganglionic system of the nerves of the
invertebrates to the cerebro-spinal system of the vertebrates have
occurred?--and, especially, how could the first deposit of the vertebral
column have procured any benefit to the individual in the struggle for
existence? We quote this objection from Karl Planck's "Wahrheit und
Flachheit des Darwinismus," ("Truth and Platitude of Darwinism"),
Nördlingen, Beck, 1872.
Still more striking is the insufficiency of the selection theory for the
explanation of the origin of the organs of motion in the higher classes of
vertebrates. A. W. Volkman says of it, in his instructive lecture, "Zur
Entwickelung der Organismen," ("Development of the Organisms") Halle,
Schmidt, 1875, p. 3 ff.: "Without doubt, animals with extremities will come
from animals which lacked extremities. Now if the metamorphosis originated
in the course of one generation, the animals with extremities would have an
advantage over the rest, which ought to show itself in the natural
selection; but if the development of an extremity needs 10,000 generations,
the individual in which the process of the development begins produces
1/10000 of the extremity and the advantage, resulting therefrom is reduced
to zero. For an organ can only be of advantage when it performs its
functions; and on {106} the first of the 10,000 stages of development the
extremity can not perform its functions. Just think of the cetacea! Of the
hind extremity, only its carrier, the pelvis, has been developed; and even
this is only represented by the two hip-bones, hanging in the flesh. As to
the python, the hind extremities are more complete, but they lie hidden
under the skin, and therefore are of no use for local movement. Such
examples show that in the history of the development of an organ thousands
of years may pass, and numerous generations may arise and disappear, until
it reaches that grade of perfection where it is of use to its owner. How
therefore, can we look upon such an organ, when finally it is perfect, as a
product of selection in the sense of Darwin?"
We find the scientific objections to the selection theory collected in
detail in the before-mentioned works of Wigand, Blanchard, His, von Baer,
and especially in Mivart's "Genesis of Species," (London, MacMillan, 1871);
and it is a praiseworthy testimony of Darwin's love of truth, that lately
he himself, the originator of the selection theory, willingly admits these
weak points in his theory,[7] while Häckel and many of his followers {107}
in Germany still stoutly reject every doubt of the autocracy of the
selection principle.
In summing up all we have said thus far about the theories of descent, of
evolution, and of selection, we still find all three solutions of the
scientific problems to be hypotheses, but hypotheses of very different
value. The idea of descent has the most scientific ground; it will, as a
permanent presupposition, govern all scientific investigations as to the
origin of species, even if it does not exclude the idea of an
often-repeated primitive generation of organisms--especially of those that
stand still lower in development. More uncertain and less comprehensive is
the position of the evolution theory; in all likelihood, the idea of an
origin through development will have to share the sovereignty with the idea
of origin by leaps through metamorphosis of germs. Still more unfavorable
is the state of the selection theory. It possesses the merit of having
started the whole question as to the origin of species; it may explain
subordinary developments; natural selection may have coöperated as a
regulator in the whole progress and the whole preservation of organic life.
Ed. von Hartmann, in his essay, "Truth and Error of Darwinism," (Berlin,
Duncker, 1875), on page 111, compares its functions with those of the bolt
and coupling in a machine; but that the driving principle which called new
species into existence lay or originated _in_ the organisms, and did not
approach them from without, seems to be confirmed more and more decidedly
with every new step of exact investigation as well as of reflection.
* * * * * {108}
BOOK II.
THE PHILOSOPHIC SUPPLEMENTS AND CONSEQUENCES OF THE DARWINIAN THEORIES.
* * * * *
THE PHILOSOPHIC PROBLEMS.
Although, in accordance with the requirements of the task before us, we
have to restrict ourselves to giving the results of natural science only in
their general outlines, still we believe that we have not overlooked any
essential result which is of importance to the question of the origin of
species and of man. We have now finished our scientific review; and the
conclusion to which we see ourselves brought is that natural science, in
its investigation of the origin of species, has arrived at nothing but
problems which it is not able to solve. There is a very great probability
of an origin of species, at least of the higher organized species, through
descent; but whether through descent by means of gradual development or of
metamorphosis of germs, or whether with one group of organisms it is in
this way, with another in that, is not yet decided. The attempt to explain
their entire origin exclusively by the selection theory, must be regarded
as a failure; all indications rather show that, supposing the descent
principle correct, the deciding agencies which formed new species did not
approach the old species out of which the new ones originated from {109}
without, but that they originated or were already in existence within them.
But what these agencies were, natural science is at present unable to
state; and not only those scientists who reject every idea of a descent,
but also those who are favorable to the ideas of descent and of evolution,
rejecting only the selection theory, are at one in silent or open
acknowledgment of this limit of our knowledge, be it permanent or
temporary.
But now the question arises: does the search after these agencies
henceforth remain the exclusive task of natural science, and have we
therefore simply to wait and see whether it will succeed in finding them?
or have we to look for the answer to these questions, which natural science
can no longer give, in another science--namely, philosophy? The first
question we will have to answer in the affirmative, the second in the
negative. It is certainly understood that _metaphysical_ principles must
underlie all _physical_ appearances; and the right to define these
principles, so far as they can be known, is willingly conceded to
philosophy by the scientists, with the exception of those of materialistic
and naturalistic tendencies. This mutual re-approaching of philosophy and
natural science is one of the most gratifying, and, to both, most fruitful
evidences of the intellectual work of the present generation. But these
metaphysical principles themselves become cognizable only when the physical
effects, whose cause they are, become accessible to our knowledge; and
every attempt to find them _a priori_, or only to extend them _a priori_,
will always fail through the opposition of empirical facts; or even if this
attempt accommodates itself to the existing state of knowledge at a given
time, it will always be overcome by the {110} progress of the empirical
sciences. In the most favorable case, it can claim the value of a
hypothesis which has to be put to the proof, whether it can be empirically
confirmed and whether we can successfully operate with it in knowing the
world of realities. But herewith it leaves the realm of pure philosophy,
and makes the question of its right to exist dependent upon the decision of
natural science.
Since the decline of the doctrines of nature held by Schelling, Steffens,
and Hegel, there has come to our knowledge, from the domain of philosophy,
but one earnest attempt to explain the origin and development of organisms
down to the concrete differences between single types, classes, and even
orders and families, from one single metaphysical principle; and this
attempt has been made by an antagonist of the descent doctrine. K. Ch.
Planck, in "Seele und Geist, oder Ursprung, Wesen und Thätigkeitsform der
physischen und geistigen Organisation von den naturwissenschaftlichen
Grundlagen aus allgemein fasslich entwickelt" ("Soul and Spirit, or Origin,
Nature, and Form of Activity of Physical and Intellectual Organization,
Clearly Developed from a Scientific Basis"), Leipzig, Fues, 1871, and in
"Wahrheit und Flachheit des Darwinismus" ("Truth and Platitude of
Darwinism"), Nördlingen, Beck, 1872, makes the "inner concentration" the
moving principle of the whole development of the world. He thinks that what
belongs to the organism and to the soul has originated and developed up to
man and his spiritual nature thus: that the creating centrum of the earth
produces individual centra on its periphery, which tend more and more to
bring into view the principle of {111} centralization, in its contrast to
the purely peripheral form of existence, until it reaches its goal in man,
with his centralizing spirit. We have no reason to reject the idea of a
principle of concentration in the world and its parts; it is confirmed by
observation, and shows itself fruitful in many respects. But in spite of
the many ingenious and often suggestive ideas in the works of Planck, we
have some doubt about a system which tries to explain the whole concrete
abundance of the richness of formations and life-forms in the world, rising
higher and higher up to spiritual existence and moral action, from the
single idea of concentration, and makes this principle the mystical and
mysteriously acting cause of a whole world and its contents. We doubt at
the outset the success of this argument. We have especially the strongest
objections to a philosophical system which submits all the contending
physical theories of the present to the measure of that concentration
principle, and from these purely metaphysical reasons takes side
exclusively with the one or the other of the theories, or establishes new
theories--from the theories of atoms and ether, of light and heat, down to
geological questions as to whether universal revolutions of the world or a
continual development took place. The solution of all these questions, in
their full extent, we do not attribute to philosophy, but to natural
science; although to a natural science which permits philosophy to define
the ideas with which it operates and the general principles to which it
comes. For this renunciation--which philosophy, however, can not at all
escape--it will be the more richly rewarded in this, that it obtains the
more certainly for its own work sure and sifted material. But all attempts
which can not {112} submit to this renunciation, give only an apparent
right to that view which Albert Lange, in his "History of Materialism,"
defends, when he banishes speculative philosophy to the realm of
imagination.
But in rejecting philosophy in the question of the causes of the
development and organization of the organic kingdoms, we did not reach the
end of the philosophic problems with which we are confronted. This whole
question is itself only a segment of the problems before which we stand,
and leads of necessity to other questions.
Already within the series of development of the organic world, so far as it
is investigated by natural science, we have found and named a point (at the
end of § 1, Chap. II, Book I), where the competency of pure natural science
comes to an end, and the question arises whether another source of
knowledge--_i.e._, even philosophy--can not take up the investigation where
natural science completes its task. This point was the _origin of
self-consciousness_ and of _free moral self-determination_; consequently,
the origin of that which makes man _man_. Going still farther back on the
temporal and ideal scale of organic beings, we arrive at another point,
which natural science no longer can explain, and that is the _origin of
sensation_ and of _consciousness_. With the appearance of sensation and
consciousness, the _animal world_ came into existence. Moreover, the whole
scientific question as to the origin and development of species, so far as
we have hitherto treated it, started from initial points where the organic
and life already existed; it, therefore, leads of necessity to the further
question as to _the origin of the organic and of life itself_. D. F.
Strauss, {113} in his "Postscript as Preface," thus clearly and simply
characterizes these still unfilled blanks in the evolution theory: "There
are, as is well known, three points in the rising development of nature, to
which the appearance of incomprehensibility especially adheres (to speak
more categorically: which have not been explained thus far by anybody). The
three questions are: How has the living sprung from that which is without
life? the sentient (and conscious) being from that which is without
sensation? that which possesses reason (self-consciousness and free will)
from that which is without reason?--questions equally embarrassing to
thought." But even the question as to the origin of the organic and of life
can not be discussed without an investigation, leading us farther back to
the question as to _the elements of the world_ in general. The _doctrine of
atoms_, and the _mechanical view of the world_, are the scientific
evidences of the efforts in this direction.
So far as the attempts to solve these four questions start from the results
of natural science and, from this starting-point of the known, try to solve
the unknown, we will have to assign them in the encyclopædic classification
of the sciences, to that department of philosophy which treats the
doctrines of nature; and since our whole investigation starts from the
Darwinian theories, and only tries to treat of what is properly connected
with them, the attempts to solve these four questions offer themselves as
the _naturo-philosophic supplements of the Darwinian-theories_.
After concluding our treatment of them, we shall have to speak of still
another view, which presupposes all these attempts at solution to be wholly
or nearly {114} successful, and draws an inference from them which no
longer belongs to the realm of natural science, but is a purely
_metaphysical_ hypothesis; it is the _abolition of the idea of design in
nature_. In connection with this, finally, we shall have to discuss the
name which this view has lately assumed, viz: "_Monism_."
Whatever further questions may arise, belong either to the special
subdivisions of natural science and philosophy, or to theological and
ethical problems.
* * * * * {115}
CHAPTER I.
THE NATURO-PHILOSOPHIC SUPPLEMENTS OF THE DARWINIAN THEORIES.
§ 1. _The Origin of Self-Consciousness and of Free Moral
Self-Determination._
If sensation, and its most developed form, consciousness, is a reflex of
the material in something immaterial, which feels itself a unit in contrast
to the material, and, where sensation rises into consciousness, is opposed
as a unit to the material--self-consciousness again is the reflex of this
sentient and conscious subject in a new and still higher immaterial unity;
and this again makes this sentient and conscious subject, together with the
sum of its feelings and ideas, its object, changing it from a sentient and
conscious subject into a felt and presented object. Therefore it is clear,
and will be the result of all thought upon these concepts, that as with
sensation and consciousness, so also with self-consciousness, something new
always comes into existence--a higher category of being, different from the
merely material. The first is the form of being of the animal world; the
latter that of mankind.
It is exactly the same with the first appearance of voluntary movement, and
again with that of free moral self-determination. The reaction of the
sentient subject upon his sensations is something qualitatively different
from the purely mechanical and physical action and {116} reaction of pure
matter; although, in order to understand the possibility of a sensation as
well as of a voluntary movement, we must admit that the physical qualities
of matter must be such as to afford a basis and condition for sentient and
reacting beings. That reaction is the reaction of something immaterial upon
the material, even if it is entirely caused by the material and bound to
the material. Now, with free moral self-determination a new subject comes
into existence and activity in the individual, which makes that subject,
reacting upon mere sensations and ideas, its object, and, as a new
immaterial subjective unity, acts determiningly upon that subject which has
just become object. This new subject, considered from the side of its
receptivity, we call _self-consciousness_; from the side of its
spontaneity, _free moral self-determination_. Whether we consider this
freedom predetermined or not, does not at all alter the described fact and
the qualitative difference between the form of human moral agency and that
of purely animal spontaneity. For even those advocating determination must
admit that the morally acting subject distinguishes itself from its object,
and does not take its motives to action from the material and from the
instinctive life which is bound to the sensual and dependent on it.
Now it is true that all these circumstances in organized individuals which
serve self-consciousness and free moral self-determination as their
condition, presupposition, and basis, all the dispositions of the soul and
the manifestations of life found in the animal world, will be worthy of the
closest attention even on this account: because they form the basis, the
condition, and (if self-consciousness and freedom are once present) an
essential {117} part of the contents and object of self-consciousness and
moral self-determination. But where the origin of man is discussed, the
central point of the investigation is no longer the enumeration of those
activities of the soul of man whose analogies we also find in the animal
world, but rather in the answer to the question as to how that entirely new
manifestation, self-consciousness and moral self-determination, came into
existence or could have originated. This question is the more decidedly the
central point of the investigation, since this new form, when once in
existence, has for its object not only what already appears in the life of
the soul of animals, but also receives a new object, which can only be an
object of self-consciousness and of moral self-determination, and not of
mere consciousness and instinctive life. These new objects are the ideas
leading up to the conception of God and moral ideals.
Now this very question as to the origin of self-consciousness and of free
moral self-determination is wholly misjudged as to its importance, and
given remarkably little attention by those evolutionists who are well
versed in the realm of natural science. The question as to the origin of
self-consciousness is either entirely ignored--as if self-consciousness
must originate wholly by itself, if only those first steps of an
intellectual and social life which the animal world also shows, are once
present and properly developed--or the solution is put aside with the most
superficial analogies. The question regarding free moral
self-determination, on the other hand, is either likewise ignored, and for
the same reasons, or it is supposed that it must fail of itself, if {118}
only this self-determination is explained in a deterministic way.
It is true, Darwin devotes several chapters of his work, "Descent of Man,"
to a comparison of the intellectual powers of man with those of animals,
and these chapters are full of the most interesting facts and comparisons;
but although his work comprises two volumes, he devotes to the origin of
self-consciousness, individuality, abstraction, general ideas, etc., only a
single page, and justifies his brief treatment with the assertion that the
attempt at discussing these higher faculties is useless, because hardly two
authors agree in their definitions of these terms. What he says about
self-consciousness is really contained in two sentences, namely: "But how
can we feel sure that an old dog with an excellent memory and some power of
imagination, as shown by his dreams, never reflects on his past pleasures
or pains in the chase? This would be a form of self-consciousness." On the
other hand, as Büchner has remarked in his "Lectures about Darwin's
Theory": "How little can the hard-working wife of a degraded Australian
savage, who hardly ever uses abstract words, and can not count above four,
how little can such a woman exert her self-consciousness, or reflect on the
nature of her own existence!" And in Darwin's _resumé_ of his chapters on
the intellectual powers of man and animals, he says, on page 126: "If it
could be proved that certain high mental powers, such as the formation of
general concepts, self-consciousness, etc., were absolutely peculiar to
man, which seems extremely doubtful, it is not improbable that these
qualities are merely the incidental results of other highly-advanced
intellectual faculties: {119} and these again mainly the result of the
continued use of a perfect language."
If Darwin is thus not able to show us in the animal world a single real
analogy which at all approaches self-consciousness, and, in order to supply
this want, must have recourse to the purely hypothetical _possibility_ that
it is not certain whether an old hunting-dog does not reflect upon the past
joys of the chase; if by the uncertainty of the expression that
self-consciousness might be an "_accompanying_" result of other faculties,
he nevertheless gives us to understand that he can not find the
_sufficient_ cause of the origin of self-consciousness in those other
faculties; and, finally, if he closes the last mentioned quotation with a
sentence which has for its premise the wholly illogical thought that
language might have been able to reach "a high state of development" before
the origin of self-consciousness and without its assistance: then, indeed,
the result of all this certainly is that he has given no adequate
consideration to the specific nature of self-consciousness. It is only
under this supposition that it is possible for him to say: "Nevertheless,
the difference in mind between man and the higher animals, great as it
certainly is, is one of degree and not of quality." The authors may
possibly not agree in the definitions of the idea of self-consciousness--we
ourselves perhaps are only an additional example in confirmation of this
fact--; but whatever the definition may be, the fact itself remains, that
self-consciousness does not stand as one of the intellectual faculties
beside the others and coördinate with them, but, as an entirely new form of
being, introduces a qualitatively new and valuable factor into the subject.
That which precedes the {120} origin of self-consciousness--the purely
conscious and not yet self-conscious life of the soul, as it shows itself
with higher animals, especially with mammals--_may_ have been the necessary
condition and requirement for the origin of self-consciousness. It
certainly _has_ been so; and from this point of view, all these
psychological studies of animals and psycho-physical investigations which
are a favorite object of modern science, have a high value; but what has
been called into existence by _means_ of conditions is not on that account
the _product_ of those conditions. This very fact is one of the greatest
mistakes of most of the modern evolution theories: that very often--and
especially where they wish to draw metaphysical conclusions from their
scientific results or hypotheses--they confound condition and basis with
cause.
Now it appears to us that, in quite an analogous way, Darwin overlooks or
contests the fact that with _free moral self-determination_ something
specifically new comes into existence. He certainly discusses the origin of
the moral qualities of man more in detail than he does the origin of his
intellectual qualities. He derives them, in their first beginnings, from
the fixity, transmission and increase of the _social_ impulses and
instincts. These, being the basis of the whole moral development, and
leading in their more mature form to love and to sympathy, originated by
natural selection; and the other moral qualities, such as moral sense and
conscience, progressed more by the effect of custom, by the power of
reflection, instruction, and religion, than by natural selection. Higher
and lower, common and special, permanent and transitory instincts come into
collision {121} with one another. The dissatisfaction of man when any of
the lower, special, and transitory instincts have overcome the higher,
common and permanent, and the resolution to act differently for the future,
is _conscience_. Darwin considers that one a _moral being_ who is capable
of comparing with one another his past and future actions and motives, of
approving some of them and of disapproving others; and the fact that man is
the only creature who can with certainty be ranked as a moral being is,
according to Darwin, the greatest of all differences between man and
animals.
Here, again, the whole central point of the investigation as to the origin
of man does not lie in the question of the origin of the instincts between
which the moral subject, acting in moral self-determination, has to choose.
For it is clear that the beginnings of these instincts are also present in
the animal world. But the main question is, how did this faculty and
necessity of choosing, this conscience and responsibility, this "moral
sense," as Darwin calls it, originate? Now to this question we have a plain
answer in the before-mentioned utterances of Darwin: It originated not as a
_product_ of the social instincts--it only has these instincts for its
preceding condition, object and instrument; but it originated as a product
of other agencies, which act upon these impulses and instincts, operate
with them, choose between them; and as these other agencies Darwin mentions
the high development of the intellectual powers. That this is his opinion,
we can clearly see from an expression with which he introduces his essay on
the origin of "moral sense": "The following proposition seems to me in a
high degree probable--namely, that {122} any animal whatever, endowed with
well-marked social instincts, would inevitably acquire a moral sense or
conscience, _as soon as its intellectual powers had become as well, or
nearly as well developed, as in man_." These intellectual powers which
moral feeling and conscience require at their birth, are certainly,
according to Darwin the power to distinguish oneself as subject from one's
impulses and instincts, and to choose between them; _i.e._,
self-consciousness. We shall have to admit fully this intimate connection
between moral self-determination and self-consciousness; but we must admit,
at the same time, that moral self-determination--this new form of activity
in which moral activity distinguishes itself from all _merely_ instinctive
activity--finds its sufficient explanation in the previous stage of the
animal world as little as self-consciousness; and that moral
self-determination has the condition and presupposition, but not the cause,
of its existence in that which is also found in the previous stage of the
animal world. The proof that the origin of moral self-determination finds
its sufficient explanation in that which the previous stage of the animal
world also has, would appear to have been given by Darwin only when he had
succeeded in explaining the origin of self-consciousness from animal
intelligence; but that he did not succeed in it, we think we have clearly
shown. On the other hand, we willingly admit that the study of the social
and all other instincts and impulses which are common to man and animals,
and which in man form the object and instrument of his moral activity, has
for us the highest interest, inasmuch as the only problem is to explain the
conditions and prerequisites of moral self-determination--or, historically
speaking, the conditions {123} and prerequisites of the origin of morally
acting beings. Furthermore we have to say here also that condition and
prerequisite are not identical with cause, and it is precisely the _cause_
of moral responsibility and of the origin of such morally responsible
beings, which has not yet been discovered by the Darwinian theory.
The followers of Darwin enter still less into the discussion of the
question as to the origin of self-consciousness and of moral
self-determination. Häckel--who, in his "Natural History of Creation" and
in his "Anthropogeny," expounds his whole evolution theory in all its
antecedent conditions and consequences--has, indeed, much to say of the
different faculties of the soul of man and animals. He traces these
faculties in the case of man down to the lowest state of the most degraded
races, and in the case of animals from the kermes up to the bee, from the
lancelet-fish to the dog, ape, elephant and horse; and he also treats of
the so-called _a priori_ knowledge which "arose only by long-enduring
transmission, by inheritance of acquired adaptations of the brain, out of
originally empiric or experiential knowledge _a posteriori_," (Vol. II,
345). But we look in vain in his works for a treatment of the question as
to the origin of the Ego--of self-consciousness. Nowhere does he enter into
the analysis of the psychological ideas; he only compares the psychical
utterances of different creatures, and thinks the whole problem solved when
he says: "The mental differences between the most stupid placental animals
(for instance, sloths and armadillos) and the most intelligent animals of
the same group (for instance dogs and apes) are, at any rate, much more
considerable than the differences in the {124} intellectual life of dogs,
apes, and men." Or: "If these brutish parasites are compared with the
mentally active and sensitive ants, it will certainly be admitted that the
psychical differences between the two are much greater than those between
the highest and lowest mammals--between beaked animals, pouched animals and
armadillos, on the one hand, and dogs, apes, men, on the other." The fact
that in the human individual consciousness and self-consciousness are
gradually developed, is to him a proof that in the organic kingdom also
consciousness and self-consciousness came into existence gradually, and,
indeed, hand-in-hand with the development of the nervous system; and with
this result he thinks that he has relieved himself from the task of showing
the "how" of the origin of self-consciousness. This becomes clearly evident
from a remark about the origin of consciousness, in his "Anthropogeny,"
where he says that, if DuBois-Reymond had thought that consciousness is
developed, he would no longer have held its origin to be a thing beyond the
limits of human capacity. Häckel likewise seems to regard the question of
the origin of moral self-determination as solved or rejected, if only
freedom is denied--which, indeed, is repeatedly done by him.
A similar defect in the treatment of this question by evolutionists we find
in the works of Oscar Schmidt, Gustav Jäger, and others. Even Emil
DuBois-Reymond, who, in his celebrated and eloquent lecture on "The Limits
of the Knowledge of Nature," given before the assembly of scientists at
Leipzig, 1872, asserts so energetically that the origin of sensation and
consciousness is inexplicable (see next section), seems to {125} take the
origin of self-consciousness for granted, and as needing no further
explanation, if only consciousness is once present.
Since, then, the scientists leave us without a sufficient answer to the
question respecting the origin of self-consciousness and of moral
self-determination, we shall have to turn to the philosophers. Here,
indeed, we find rich definitions and genetic analyses, but none that lead
us any farther than to the information that consciousness is the necessary
condition of self-consciousness; that animal instinct is the necessary
antecedent condition of moral self-determination. Yet in the works of these
very philosophers who are inclined to a mechanical and "monistic" view of
the world, we find that they directly avoid the question as to the origin
of self-consciousness and of moral self-determination. As soon as they are
led near it, in the course of reasoning in their works, they suddenly turn
aside again to the quite different questions of the connection between
brain and soul, between physical and psychical, external and internal
processes, etc. Evidently they feel that with this question they have
arrived at the weak point of their system. That here is a weak point, we
clearly see in the case of D. F. Strauss, a leading advocate of modern
naturalism, and the greatest philosophic scholar of that school. It is
true, in his "Postscript as Preface," as we saw before, he mentions the
origin of self-consciousness as one of the points which need special
explanation; but he seems to have made this acknowledgment more with the
purpose of showing that DuBois-Reymond, in admitting the origin of
self-consciousness to be explainable, has no longer any reason to contest
the explicability of the {126} origin of sensation and consciousness; for
in his work on "The Old Faith and the New," he did not enter into that
question at all. On the other hand, he makes in his last-mentioned work a
remarkable confession. In answering the question--how do we determine our
rule of life?--he comes to speak of the position of man in nature, traces a
law of progress in nature, and says: "In this cumulative progression of
life, man is also comprised, and, moreover, in such wise that the organic
plasticity of our planet (provisionally, say some naturalists, but that we
may fairly leave an open question) culminates in him. _As nature can not go
higher, she would go inwards._ 'To be reflected within itself,' was a very
good expression of Hegel's. Nature felt herself already in the animal, but
she wished to know herself also." But still stronger is the following
expression: "_In man, nature endeavored not merely to exalt, but to
transcend herself._" In § 1, Chap. II, we shall have to speak of this
important acknowledgment of teleology in nature, which such an antagonist
of teleology as Strauss makes in the above-quoted remarks about a progress
in nature and a will of nature; but here we are more interested in the
equally remarkable acknowledgment of the fact that man can not be explained
from nature alone--that he is something which transcends nature. For that
(according to Strauss) nature, in originating man, not only _intended_ to
transcend herself, but really did transcend herself and, that she succeeded
in her intention, we can infer from the moral precept which Strauss gives:
"Do not forget for a moment, that thou art human; not merely a natural
production."
The result of our investigation, therefore, is that {127} with
self-consciousness and free moral self-determination something specifically
new came into existence which had its antecedent condition in a previous
state of existence, but has not yet found its sufficient explanation in
this antecedent state.
§ 2. _The Origin of Sensation and of Consciousness._
The limits of our knowledge show themselves still more clearly in the
attempts to explain the origin of consciousness and its lowest
form--sensation. Self-consciousness is without doubt ideally nearer to
consciousness in this, that both are an immaterial activity; and yet we
found no demonstrable bridge which leads
Showing first 200,000 characters. Full text: gutenberg.org/ebooks/22150