The Theories of Darwin and Their Relation to Philosophy, Religion, and Morality.
by Rudolf Schmid.
PREFACE
The movement which received its impulse as well as its name from Darwin, seems to have recently pa.s.sed 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.
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 s.p.a.ce 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 Muller did in the realm of the history of religion; what the Tubingen 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 surpa.s.sed 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 n.o.blest 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 circ.u.mstances, 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 pa.s.sed 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 G.o.d. 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 G.o.d 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 G.o.d"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 circ.u.mstances 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 ma.s.sed 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 trans.m.u.tation; 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 aequivoca_, 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 a.n.a.logies of observation. The only a.n.a.logy 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 trans.m.u.tation, 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 Vertebres_,"
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 Linnaeus, 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 trans.m.u.tation 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 palaeontology and the comparative geography of plants and animals--not yet in existence. The influence of Linnaeus, 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 a.n.a.lysis 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 _role_; the different ill.u.s.trations 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 a.n.a.logy and h.o.m.ology 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 a.n.a.logies of the organisms the principles for explaining the real connection between the different organic forms, or whether the a.n.a.lytical 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 a.n.a.lytical 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 palaeontology and geology, as attained by the help of those very principles. And even physics and astronomy had to cooperate 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 ident.i.ty 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 Sch.e.l.ling; 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 a.n.a.logies 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 zoology 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 Hackel, 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 Aga.s.siz, 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 cla.s.sification, 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 palaeontological 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 palaeontological 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 zoology; and, finally, the principles of geology, which, under the leadership of Sir Charles Lyell, starting from the idea of an ident.i.ty 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 Aga.s.siz 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.