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Darwiniana - Essays and Reviews Pertaining to Darwinism
by Asa Gray
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According to these views, as regards plants at least, the adaptation to successive times and changed conditions has been maintained, not by absolute renewals, but by gradual modifications. I, for one, cannot doubt that the present existing species are the lineal successors of those that garnished the earth in the old time before them, and that they were as well adapted to their surroundings then, as those which flourish and bloom around us are to their conditions now. Order and exquisite adaptation did not wait for man's coming, nor were they ever stereotyped. Organic Nature—by which I mean the system and totality of living things, and their adaptation to each other and to the world—with all its apparent and indeed real stability, should be likened, not to the ocean, which varies only by tidal oscillations from a fixed level to which it is always returning, but rather to a river, so vast that we can neither discern its shores nor reach its sources, whose onward flow is not less actual because too slow to be observed by the ephemerae which hover over its surface, or are borne upon its bosom.

Such ideas as these, though still repugnant to some, and not long since to many, have so possessed the minds of the naturalists of the present day that hardly a discourse can be pronounced or an investigation prosecuted without reference to them. I suppose that the views here taken are little, if at all, in advance of the average scientific mind of the day. I cannot regard them as less noble than those which they are succeeding. An able philosophical writer, Miss Frances Power Cobbe, has recently and truthfully said:[V-8]

"It is a singular fact that, when we can find out how anything is done, our first conclusion seems to be that God did not do it. No matter how wonderful, how beautiful, how intimately complex and delicate has been the machinery which has worked, perhaps for centuries, perhaps for millions of ages, to bring about some beneficent result, if we can but catch a glimpse of the wheels its divine character disappears."

I agree with the writer that this first conclusion is premature and unworthy—I will add, deplorable. Through what faults or infirmities of dogmatism on the one hand, and skepticism on the other, it came to be so thought, we need not here consider. Let us hope, and I confidently expect, that it is not to last; that the religious faith which survived without a shock the notion of the fixity of the earth itself may equally outlast the notion of the fixity of the species which inhabit it; that, in the future even more than in the past, faith in an order, which is the basis of science, will not—as it cannot reasonably—be dissevered from faith in an Ordainer, which is the basis of religion.



VI

THE ATTITUDE OF

WORKING NATURALISTS

TOWARD DARWINISM [VI-1]

(The Nation, October 16, 1873)



That homely adage, "What is one man's meat is another man's poison," comes to mind when we consider with what different eyes different naturalists look upon the hypothesis of the derivative origin of actual specific forms, since Mr. Darwin gave it vogue and vigor and a raison d'tre for the present day. This latter he did, not only by bringing forward a vera causa in the survival of the fittest under changing circumstances—about which the question among naturalists mainly is how much it will explain, some allowing it a restricted, others an unlimited operation—but also by showing that the theory may be made to do work, may shape and direct investigations, the results of which must in time tell us whether the theory is likely to hold good or not. If the hypothesis of natural selection and the things thereto appertaining had not been capable of being put to useful work, although, like the "Vestiges of the Natural History of Creation," it might have made no little noise in the world, it would hardly have engaged the attention of working naturalists as it has done. We have no idea even of opening the question as to what work the Darwinian theory has incited, and in what way the work done has reacted upon the theory; and least of all do we like to meddle with the polemical literature of the subject, already so voluminous that the German bibliographers and booksellers make a separate class of it. But two or three treatises before us, of a minor or incidental sort, suggest a remark or two upon the attitude of mind toward evolutionary theories taken by some of the working naturalists.

Mr. Darwin's own expectation, that his new presentation of the subject would have little or no effect upon those who had already reached middle-age, has—out of Paris—not been fulfilled. There are, indeed, one or two who have thought it their duty to denounce the theory as morally dangerous, as well as scientifically baseless; a recent instance of the sort we may have to consider further on. Others, like the youth at the river's bank, have been waiting in confident expectation of seeing the current run itself dry. On the other hand, a notable proportion of the more active-minded naturalists had already come to doubt the received doctrine of the entire fixity of species, and still more that of their independent and supernatural origination. While their systematic work all proceeded implicitly upon the hypothesis of the independence and entire permanence of species, they were perceiving more or less clearly that the whole question was inevitably to be mooted again, and so were prepared to give the alternative hypothesis a dispassionate consideration. The veteran Lyell set an early example, and, on a reconsideration of the whole question, wrote anew his famous chapter and reversed his former and weighty opinion. Owen, still earlier, signified his adhesion to the doctrine of derivation in some form, but apparently upon general, speculative grounds; for he repudiated natural selection, and offered no other natural solution of the mystery of the orderly incoming of cognate forms. As examples of the effect of Darwin's "Origin of Species" upon the minds of naturalists who are no longer young, and whose prepossessions, even more than Lyell's, were likely to bias them against the new doctrine, two from the botanical side are brought to our notice through recent miscellaneous writings which are now before us.[VI-2]

Before the publication of Darwin's first volume, M. Alphonse de Candolle had summed up the result of his studies in this regard, in the final chapter of his classical "Geographie Botanique Raisonnee," in the conclusion, that existing vegetation must be regarded as the continuation, through many geological and geographical changes, of the anterior vegetations of the world; and that, consequently, the present distribution of species is explicable only in the light of their geological history. He surmised that, notwithstanding the general stability of forms, certain species or quasi-species might have originated through diversification under geographical isolation. But, on the other hand, he was still disposed to admit that even the same species might have originated independently in two or more different regions of the world; and he declined, as unpractical and unavailing, all attempts to apply hypotheses to the elucidation of the origin of species. Soon after Darwin's book appeared, De Candolle had occasion to study systematically a large and wide-spread genus— that of the oak. Investigating it under the new light of natural selection, he came to the conclusion that the existing oaks are all descendants of earlier forms, and that no clear line can be drawn between the diversification whic h has resulted in species and that which is exhibited in races and minor varieties.

And now, in the introductory chapter of the volume of essays before us, he informs us that the idea which pervades them all, and in some sort connects very diverse topics, is that of considering this principle of selection. Of the principle itself, he remarks that it is neither a theory nor an hypothesis, but the expression of a necessary fact; that to deny it is very much like denying that round stones will roll downhill faster and farther than flat ones; and that the question of the present day in natural history is not whether there be natural selection, or even whether forms are derived from other forms, but to comprehend how, in what proportions, and by what means hereditary deviations take place, and in what ways an inevitable selection takes effect upon these. In two of these essays natural selection is directly discussed in its application to the human race; the larger one dealing ably with the whole subject, and with results at first view seemingly in a great degree negative, but yet showing that the supposed "failure of natural selection in the case of man" was an unwarrantable conclusion from too limited a view of a very complicated question. The article abounds in acute and fertile suggestions, and its closing chapter, "on the probable future of the human species" under the laws of selection, is highly interesting and noteworthy. The other and shorter essay discusses a special point, and brings out a corollary of the law of heredity which may not have been thought of before, but which is perfectly clear as soon as it is stated. It explains at once why contagious or epidemic diseases are most fatal at their first appearance, and less so afterward: not by the dying out of a virus—for, when the disease reaches a new population, it is as virulent as ever (as, for instance, the smallpox among the Indians)—but by the selection of a race less subject to attack through the destruction of those that were more so, and the inheritance of the comparative immunity by the children and the grandchildren of the survivors; and how this immunity itself, causing the particular disease to become rare, paves the way to a return of the original fatality; for the mass of such population, both in the present and the immediately preceding generation, not having been exposed to the infection, or but little exposed, has not undergone selection, and so in time the proportion liable to attack, or to fatal attack, gets to be as large as ever. The greater the fatality, especially in the population under marriageable age, the more favorable the condition of the survivors; and, by the law of heredity, their children should share in the immunity. This explanation of the cause, or of one cause, of the return of pests at intervals no less applies to the diminution of the efficacy of remedies, and of preventive means, such as vaccination. When Jenner introduced vaccination, the small-pox in Europe and European colonies must have lost somewhat of its primitive intensity by the vigorous weeding out of the more susceptible through many generations. Upon the residue, vaccination was almost complete protection, and, being generally practised, small-pox consequently became rare. Selection thus ceasing to operate, a population arises which has not been exposed to the contagion, and of which a considerable proportion, under the common law of atavism, comes to be very much in the condition of a people invaded for the first time by the disease. To these, as we might expect, vaccination would prove a less safeguard than to their progenitors three or four generations before.

Mr. Bentham is a veteran systematic botanist of the highest rank and widest knowledge. He had not, so far as we know, touched upon questions of origination in the ante-Darwinian era. The dozen of presidential addresses delivered at anniversary meetings of the Linnean Society, from his assumption of the chair in the year 1862 down to the current year—each devoted to some topic of interest—and his recent "Memoir on Compositae," summing up the general results of a revision of an order to which a full tenth of all higher plants belong, furnish apt examples both of cautious criticism, conditional assent (as becomes the inaugurator of the quantification of the predicate), and of fruitful application of the new views to various problems concerning the classification and geographical distribution of plants. In his hands the hypothesis is turned at once to practical use as an instrument of investigation, as a means of interrogating Nature. In the result, no doubt seems to be left upon the author's mind that the existing species of plants are the result of the differentiation of previous species, or at least that the derivative hypothesis is to be adopted as that which offers the most natural, if not the only, explanation of the problems concerned. Similar conclusions reached in this country, from a study of the relations of its present flora with that which in earlier ages occupied the arctic zone, might also be referred to. (See preceding article.)

An excellent instance of the way in which the derivative hypothesis is practically applied in these days, by a zoologist, is before us in Prof. Flower's modest and admirable paper on the Ungulata, or hoofed animals, and their geological history. We refer to it here, not so much for the conclusions it reaches or suggests, as to commend the clearness and the impartiality of the handling, and the sobriety and moderation of the deductions. Confining himself "within the region of the known, it is shown that, at least in one group of animals, the facts which we have as yet acquired point to the former existence of various intermediate forms, so numerous that they go far to discredit the view of the sudden introduction of new species. . . . The modern forms are placed along lines which converge toward a common centre." The gaps between the existing forms of the odd-toed group of ungulates (of which horses, rhinoceroses, and tapirs, are the principal representatives) are most bridged over by palaeontology, and somewhat the same may be said of the even-toed group, to which the ruminants and the porcine genus belong. "Moreover, the lines of both groups to a certain extent approximate, but, within the limits of our knowledge, they do not meet. . - . Was the order according to which the introduction of new forms seems to have taken place since the Eocene then entirely changed, or did it continue as far back as the period when these lines would have been gradually fused in a common centre?"

Facts like these, which suggest grave diversification under long lapse of time, are well supplemented by those which essentially demonstrate a slighter diversification of many species over a wide range of space; whether into species or races depends partly upon how the naturalist uses these terms, partly upon the extent of the observations, or luck in getting together intermediate forms. The researches of Prof. Baird upon the birds of this continent afford a good illustration. A great number of our birds which have been, and must needs have been, regarded as very distinct species, each mainly with its own geographical area, are found to mingle their characters along bordering lines; and the same kinds of differences (of coloration, form, or other) are found to prevail through the species of each region, thus impressing upon them a geographical facies. Upon a submergence of the continent, reducing these several regions to islands sufficiently separated, these forms would be unquestioned species.

Considerations such as these, of which a few specimens have now been adduced (not general speculations, as the unscientific are apt to suppose), and trials of the new views to see how far they will explain the problems or collocate the facts they are severally dealing with, are what have mainly influenced working naturalists in the direction of the provisional acceptance of the derivative hypothesis. They leave to polemical speculators the fruitless discussion of the question whether all species came from one or two, or more; they are trying to grasp the thing by the near, not by the farther end, and to ascertain, first of all, whether it is probable or provable that present species are descendants of former ones which were like them, but less and less like them the farther back we go.

And it is worth noting that they all seem to be utterly unconscious of wrong-doing. Their repugnance to novel hypotheses is only the natural and healthy one. A change of a wonted line of thought is not made without an effort, nor need be made without adequate occasion. Some courage was required of the man who first swallowed an oyster from its shell; and of most of us the snail would still demand more. As the unaccustomed food proves to be good and satisfying, and also harmless, we may come to like it. That, however, which many good and eminent naturalists find to be healthful and reasonable, and others innocuous, a few still regard as most unreasonable and harmful. At present, we call to mind only two who not only hold to the entire fixity of species as an axiom or a confirmed principle, but also as a dogma, and who maintain, either expressly or implicitly, that the logical antithesis to the creation of species as they are, is not by law (which implies intention), but by chance. A recent book by one of these naturalists, or rather, by a geologist of eminence, the "Story of the Earth and Man," by Dr. Dawson,4 is now before us. The title is too near that of Guyot's "Earth and Man," with the publication of which popular volume that distinguished physical naturalist commenced his career in this country; and such catch-titles are a sort of trade-mark. As to the nature and merits of Dr. Dawson's work, we have left ourselves space only to say: 1. That it is addressed ad populum, which renders it rather the more than less amenable to the criticisms we may be disposed to make upon it. 2. That the author is thoroughly convinced that no species or form deserving the name was ever derived from another, or originated from natural causes; and he maintains this doctrine with earnestness, much variety of argument and illustration, and no small ability; so that he may be taken as a representative of the view exactly opposed to that which is favored by those naturalists whose essays we have been considering—to whom, indeed, he stands in marked contrast in spirit and method, being greatly disposed to argue the question from the remote rather than the near end. 3. And finally, he has a conviction that the evolutionary doctrines of the day are not only untrue, but thoroughly bad and irreligious. This belief, and the natural anxiety with which he contemplates their prevalence, may excuse a certain vehemence and looseness of statement which were better avoided, as where the geologists of the day are said to be "broken up into bands of specialists, little better than scientific banditti, liable to be beaten in detail, and prone to commit outrages on common-sense and good taste which bring their otherwise good cause into disrepute;" and where he despairingly suggests that the prevalence of the doctrines he deprecates "seems to indicate that the accumulated facts of our age have gone altogether beyond its capacity for generalization, and, but for the vigor which one sees everywhere, might be taken as an indication that the human mind has fallen into a state of senility."

This is droll reading, when one considers that the "evolutionist" is the only sort of naturalist who has much occasion to employ his "capacity for generalization" upon "the accumulated facts" in their bearing upon the problem of the origin of species; since the "special creationist," who maintains that they were supernaturally originated just as they are, by the very terms of his doctrine places them out of the reach of scientific explanation. Again, when one reflects upon the new impetus which the derivative hypothesis has given to systematic natural history, and reads the declaration of a master in this department (the President of the Linnean Society) that Mr. Darwin "has in this nineteenth century brought about as great a revolution in the philosophic study of organic Nature as that which was effected in the previous century by the immortal Swede," it sounds oddly to hear from Dr. Dawson that "it obliterates the fine perception of differences from the mind of the naturalist, . . . . destroys the possibility of a philosophical classification, reducing all things to a mere series, and leads to a rapid decay in systematic zoology and botany, which is already very manifest among the disciples of Spencer and Darwin in England." So, also, "it removes from the study of Nature the ideas of final cause and purpose"—a sentence which reads curiously in the light of Darwin's special investigations, such as those upon the climbing of plants, the agency of insects in the fertilization of blossoms, and the like, which have brought back teleology to natural science, wedded to morphology and already fruitful of discoveries. The difficulty with Dr. Dawson here is (and it need not be underrated) that apparently he cannot as yet believe an adaptation, act, or result, to be purposed the apparatus of which is perfected or evolved in the course of Nature—a common but a crude state of mind on the part of those who believe that there is any originating purpose in the universe, and one which, we are sure, Dr. Dawson does not share as respects the material world until he reaches the organic kingdoms, and there, possibly, because he sees man at the head of them—of them, while above them. However that may be, the position which Dr. Dawson chooses to occupy is not left uncertain. After concluding, substantially, that those "evolutionists" who exclude design from Nature thereby exclude theism, which nobody will deny, he proceeds (on page 348) to give his opinion that the "evolutionism which professes to have a creator somewhere behind it . . . . is practically atheistic," and, "if possible, more unphilosophical than that which professes to set out from absolute and eternal nonentity," etc.

There are some sentences which might lead one to suppose that Dr. Dawson himself admitted of an evolution "with a creator somewhere behind it." He offers it (page 320) as a permissible alternative that even man "has been created mediately by the operation of forces also concerned in the production of other animals;" concedes that a just theory "does not even exclude evolution or derivation, to a certain extent" (page 341); and that "a modern man of science" may safely hold "that all things have been produced by the Supreme Creative Will, acting either directly or through the agency of the forces and materials of his own production." Well, if this be so, why denounce the modern man of science so severely upon the other page merely for accepting the permission? At first sight, it might be thought that our author is exposing himself in one paragraph to a share of the condemnation which he deals out in the other. But the permitted views are nowhere adopted as his own; the evolution is elsewhere restricted within specific limits; and as to "mediate creation," although we cannot divine what is here meant by the term, there is reason to think it does not imply that the several species of a genus were mediately created, in a natural way, through the supernatural creation of a remote common ancestor. So that his own judgment in the matter is probably more correctly gathered from the extract above referred to and other similar deliverances, such as that in which he warns those who "endeavor to steer a middle course, and to maintain that the Creator has proceeded by way of evolution," that "the bare, hard logic of Spencer, the greatest English authority on evolution, leaves no place for this compromise, and shows that the theory, carried out to its legitimate consequences, excludes the knowledge of a Creator and the possibility of his work."

Now, this is a dangerous line to take. Those defenders of the faith are more zealous than wise who must needs fire away in their catapults the very bastions of the citadel, in the defense of outposts that have become untenable. It has been and always will be possible to take an atheistic view of Nature, but far more reasonable from science and philosophy only to take a theistic view. Voltaire's saying here holds true: that if there were no God known, it would be necessary to invent one. It is the best, if not the only, hypothesis for the explanation of the facts. Whether the philosophy of Herbert Spencer (which is not to our liking) is here fairly presented, we have little occasion and no time to consider. In this regard, the close of his article No. 12 in the Contemporary Review shows, at least, his expectation of the entire permanence of our ideas of cause, origin, and religion, and predicts the futility of the expectation that the "religion of humanity" will be the religion of the future, or "can ever more than temporarily shut out the thought of a Power, of which humanity is but a small and fugitive product, which was in its course of ever-changing manifestation before humanity was, and will continue through other manifestations when humanity has ceased to be." If, on the one hand, the philosophy of the unknowable of the Infinite may be held in a merely quasi-theistic or even atheistic way, were not its ablest expounders and defenders Hamilton and Dean Mansel? One would sup-pose that Dr. Dawson might discern at least as much of a divine foundation to Nature as Herbert Spencer and Matthew Arnold; might recognize in this power that "something not ourselves that makes" for order as well as "for righteousness," and which he fitly terms supreme creative will; and, resting in this, endure with more complacency and faith the inevitable prevalence of evolutionary views which he is powerless to hinder. Although he cannot arrest the stream, he might do something toward keeping it in safe channels.

We wished to say something about the way in which scientific men, worthy of the name, hold hypotheses and theories, using them for the purpose of investigation and the collocation of facts, yielding or withholding assent in degrees or provisionally, according to the amount of verification or likelihood, or holding it long in suspense; which is quite in contrast to that of amateurs and general speculators (not that we reckon Dr. Dawson in this class), whose assent or denial seldom waits, or endures qualification. With them it must on all occasions be yea or nay only, according to the letter of the Scriptural injunction, and whatsoever is less than this, or between the two, cometh of evil.



VII

EVOLUTION AND

THEOLOGY [VII-1]

(The Nation, January 15, 1874)



The attitude of theologians toward doctrines of evolution, from the nebular hypothesis down to "Darwinism," is no less worthy of consideration, and hardly less diverse, than that of naturalists. But the topic, if pursued far, leads to questions too wide and deep for our handling here, except incidentally, in the brief notice which it falls in our way to take of the Rev. George Henslow's recent volume on "The Theory of Evolution of Living Things." This treatise is on the side of evolution, "considered as illustrative of the wisdom and beneficence of the Almighty." It was submitted for and received one of the Actonian prizes recently awarded by the Royal Institution of Great Britain. We gather that the staple of a part of it is worked up anew from some earlier discourses of the author upon "Genesis and Geology," "Science and Scripture not antagonistic," etc.

In coupling with it a chapter of the second volume of Dr. Hodge's "Systematic Theology (Part II, Anthropology)," we call attention to a recent essay, by an able and veteran writer, on the other side of the question. As the two fairly enough represent the extremes of Christian thought upon the subject, it is convenient to review them in connection. Theologians have a short and easy, if not wholly satisfactory, way of refuting scientific doctrines which they object to, by pitting the authority or opinion of one savant against another. Already, amid the currents and eddies of modern opinion, the savants may enjoy the same advantage at the expense of the divines— we mean, of course, on the scientific arena; for the mutual refutation of conflicting theologians on their own ground is no novelty. It is not by way of offset, however, that these divergent or contradictory views are here referred to, but only as an illustration of the fact that the divines are by no means all arrayed upon one side of the question in hand. And indeed, in the present transition period, until some one goes much deeper into the heart of the subject, as respects the relations of modern science to the foundations of religious belief, than either of these writers has done, it is as well that the weight of opinion should be distributed, even if only according to prepossessions, rather than that the whole stress should bear upon a single point, and that perhaps the authority of an interpretation of Scripture. A consensus of opinion upon Dr. Hodge's ground, for instance (although better guarded than that of Dr. Dawson), if it were still possible, would—to say the least—probably not at all help to reconcile science and religion. Therefore, it is not to be regretted that the diversities of view among accredited theologians and theological naturalists are about as wide and as equably distributed between the extremes (and we may add that the views themselves are quite as hypothetical) as those which prevail among the various naturalists and natural philosophers of the day.

As a theologian, Mr. Henslow doubtless is not to be compared with the veteran professor at Princeton. On the other hand, he has the advantage of being a naturalist, and the son of a naturalist, as well as a clergyman: consequently he feels the full force of an array of facts in nature, and of the natural inferences from them, which the theological professor, from his Biblical standpoint, and on his implicit assumption that the Old Testament must needs teach true science, can hardly be expected to appreciate. Accordingly, a naturalist would be apt to say of Dr. Hodge's exposition of "theories of the universe" and kindred topics—and in no captious spirit— that whether right or wrong on particular points, he is not often right or wrong in the way of a man of science.

Probably from the lack of familiarity with prevalent ideas and their history, the theologians are apt to suppose that scientific men of the present day are taking up theories of evolution in pure wantonness or mere superfluity of naughtiness; that it would have been quite possible, as well as more proper, to leave all such matters alone. Quieta non movere is doubtless a wise rule upon such subjects, so long as it is fairly applicable. But the time for its application in respect to questions of the origin and relations of existing species has gone by. To ignore them is to imitate the foolish bird that seeks security by hiding its head in the sand. Moreover, the naturalists did not force these questions upon the world; but the world they study forced them upon the naturalists. How these questions of derivation came naturally and inevitably to be revived, how the cumulative probability that the existing are derived from preexisting forms impressed itself upon the minds of many naturalists and thinkers, Mr. Henslow has briefly explained in the introduction and illustrated in the succeeding chapters of the first part of his book. Science, he declares, has been compelled to take up the hypothesis of the evolution of living things as better explaining all the phenomena. In his opinion, it has become "infinitely more probable that all living and extinct beings have been developed or evolved by natural laws of generation from preexisting forms, than that they, with all their innumerable races and varieties, should owe their existences severally to Creative fiats." This doctrine, which even Dr. Hodge allows may possibly be held in a theistic sense, and which, as we suppose, is so held or viewed by a great proportion of the naturalists of our day, Mr. Henslow maintains is fully compatible with dogmatic as well as natural theology; that it explains moral anomalies, and accounts for the mixture of good and evil in the world, as well as for the merely relative perfection of things; and, finally, that "the whole scheme which God has framed for man's existence, from the first that was created to all eternity, collapses if the great law of evolution be suppressed." The second part of his book is occupied with a development of this line of argument. By this doctrine of evolution he does not mean the Darwinian hypothesis, although he accepts and includes this, looking upon natural selection as playing an important though not an unlimited part. He would be an evolutionist with Mivart and Owen and Argyll, even if he had not the vera causa which Darwin contributed to help him on. And, on rising to man, he takes ground with Wallace, saying:

"I would wish to state distinctly that I do not at present see any evidence for believing in a gradual development of man from the lower animals by ordinary natural laws; that is, without some special interference, or, if it be preferred, some exceptional conditions which have thereby separated him from all other creatures, and placed him decidedly in advance of them all. On the other hand, it would be absurd to regard him as totally severed from them. It is the great degree of difference I would insist upon, bodily, mental, and spiritual, which precludes the idea of his having been evolved by exactly the same processes, and with the same limitations, as, for example, the horse from the palaeotherium."

In illustrating this view, he reproduces Wallace's well-known points, and adds one or two of his own. We need not follow up his lines of argument. The essay, indeed, adds nothing material to the discussion of evolution, although it states one side of the case moderately well, as far as it goes.

Dr. Hodge approaches the subject from the side of systematic theology, and considers it mainly in its bearing upon the origin and original state of man. Under each head he first lays down "the Scriptural doctrine," and then discusses "anti-Scriptural theories," which latter, under the first head, are the heathen doctrine of spontaneous generation, the modern doctrine of spontaneous generation, theories of development, specially that of Darwin, the atheistic character of the theory, etc. Although he admits "that there is a theistic and an atheistic form of the nebular hypothesis as to the origin of the universe, so there may be a theistic interpretation of the Darwinian theory," yet he contends that "the system is thoroughly atheistic," notwithstanding that the author "expressly acknowledges the existence of God." Curiously enough, the atheistic form of evolutionary hypotheses, or what he takes for such, is the only one which Dr. Hodge cares to examine. Even the "Reign of Law" theory, Owen's "purposive route of development and chance . . . . by virtue of inherent tendencies thereto," as well as other expositions of the general doctrine on a theistic basis, are barely mentioned without a word of comment, except, perhaps, a general "protest against the arraying of probabilities against the teachings of Scripture."

Now, all former experience shows that it is neither safe nor wise to pronounce a whole system "thoroughly atheistic" which it is conceded may be held theistically, and which is likely to be largely held, if not to prevail, on scientific grounds. It may be well to remember that, "of the two great minds of the seventeenth century, Newton and Leibnitz, both profoundly religious as well as philosophical, one produced the theory of gravitation, the other objected to that theory that it was subversive of natural religion; also that the nebular hypothesis—a natural consequence of the theory of gravitation and of the subsequent progress of physical and astronomical discovery—has been denounced as atheistical even down to our day." It has now outlived anathema.

It is undeniable that Mr. Darwin lays himself open to this kind of attack. The propounder of natural selection might be expected to make the most of the principle, and to overwork the law of parsimony in its behalf. And a system in which exquisite adaptation of means to ends, complicated inter-dependencies, and orderly sequences, appear as results instead of being introduced as factors, and in which special design is ignored in the particulars, must needs be obnoxious, unless guarded as we suppose Mr. Darwin might have guarded his. ground if he had chosen to do so. Our own opinion, after long consideration, is, that Mr. Darwin has no atheistical intent; and that, as respects the test question of design in Nature, his view may be made clear to the theological mind by likening it to that of the "believer in general but not in particular Providence." There is no need to cull passages in support of this interpretation from his various works while the author—the most candid of men—retains through all the editions of the "Origin of Species" the two mottoes from Whewell and Bishop Butler.[VII-2]

The gist of the matter lies in the answer that should be rendered to the questions—1. Do order and useful-working collocation, pervading a system throughout all its parts, prove design? and, 2. Is such evidence negatived or invalidated by the probability that these particular collocations belong to lineal series of such in time, and diversified in the course of Nature—grown up, so to say, step by step? We do not use the terms "adaptation, "arrangement of means to ends," and the like, because they beg the question in stating it.

Finally, ought not theologians to consider whether they have not already, in principle, conceded to the geologists and physicists all that they are asked to concede to the evolutionists; whether, indeed, the main natural theological difficulties which attend the doctrine of evolution—serious as they may be—are not virtually contained in the admission that there is a system of Nature with fixed laws. This, at least, we may say, that, under a system in which so much is done "by the establishment of general laws," it is legitimate for any one to prove, if he can, that any particular thing in the natural world is so done; and it is the proper business of scientific men to push their enquiries in this direction.

It is beside the point for Dr. Hodge to object that, "from the nature of the case, what concerns the origin of things cannot be known except by a supernatural revelation;" that "science has to do with the facts and laws of Nature: here the question concerns the origin of such facts." For the very object of the evolutionists, and of Mr. Darwin in particular, is to remove these subjects from the category of origination, and to bring them under the domain of science by treating them as questions about how things go on, not how they began. Whether the succession of living forms on the earth is or is not among the facts and laws of Nature, is the very matter in controversy.

Moreover, adds Dr. Hodge, it has been conceded that in this matter "proofs, in the proper sense of the word, are not to be had; we are beyond the region of demonstration, and have only probabilities to consider." Wherefore "Christians have a right to protest against the arraying of probabilities against the clear teachings of Scripture." The word is italicized, as if to intimate that probabilities have no claims which a theologian is bound to respect. As to arraying them against Scripture, there is nothing whatever in the essay referred to that justifies the statement. Indeed, no occasion offered; for the writer was discussing evolution in its relations to theism, not to Biblical theology, and probably would not be disposed to intermix arguments so different in kind as those from natural science and those from revelation. To pursue each independently, according to its own method, and then to compare the results, is thought to be the better mode of proceeding. The weighing of probabilities we had regarded as a proper exercise of the mind preparatory to forming an opinion. Probabilities, hypotheses, and even surmises, whatever they may be worth, are just what, as it seems to us, theologians ought not to be foremost in decrying, particularly those who deal with the reconciliation of science with Scripture, Genesis with geology, and the like. As soon as they go beyond the literal statements even of the English text, and enter into the details of the subject, they find ample occasion and display a special aptitude for producing and using them, not always with very satisfactory results. It is not, perhaps, for us to suggest that the theological army in the past has been too much encumbered with impedimenta for effective aggression in the conflict against atheistic tendencies in modern science; and that in resisting attack it has endeavored to hold too much ground, so wasting strength in the obstinate defense of positions which have become unimportant as well as untenable. Some of the arguments, as well as the guns, which well served a former generation, need to be replaced by others of longer range and greater penetration.

If the theologians are slow to discern the signs and exigencies of the times, the religious philosophical naturalists must be looked to. Since the above remarks were written, Prof. Le Conte's "Religion and Science," just issued, has come to our hands. It is a series of nineteen Sunday lectures on the relation of natural and revealed religion, prepared in the first instance for a Bible-class of young men, his pupils in the University of South Carolina, repeated to similar classes at the University of California, and finally delivered to a larger and general audience. They are printed, the preface states, from a verbatim report, with only verbal alterations and corrections of some redundancies consequent upon extemporaneous delivery. They are not, we find, lectures on science under a religious aspect, but discourses upon Christian theology and its foundations from a scientific layman's point of view, with illustrations from his own lines of study. As the headings show, they cover, or, more correctly speaking, range over, almost the whole field of theological thought, beginning with the personality of Deity as revealed in Nature, the spiritual nature and attributes of Deity, and the incarnation; discussing by the way the general relations of theology to science, man, and his place in Nature; and ending with a discussion of predestination and free-will, and of prayer in relation to invariable law—all in a volume of three hundred and twenty-four duodecimo pages! And yet the author remarks that many important subjects have been omitted because he felt unable to present them in a satisfactory manner from a scientific point of view. We note, indeed, that one or two topics which would naturally come in his way—such, especially, as the relation of evolution to the human race—are somewhat conspicuously absent. That most of the momentous subjects which he takes up are treated discursively, and not exhaustively, is all the better for his readers. What they and we most want to know is, how these serious matters are viewed by an honest, enlightened, and devout scientific man. To solve the mysteries of the universe, as the French lady required a philosopher to explain his new system, "dans un mot," is beyond rational expectation.

All that we have time and need to say of this little book upon great subjects relates to its spirit and to the view it takes of evolution. Its theology is wholly orthodox; its tone devotional, charitable, and hopeful; its confidence in religious truth, as taught both in Nature and revelation, complete; the illustrations often happy, but often too rhetorical; the science, as might be expected from this author, unimpeachable as regards matters of fact, discreet as to matters of opinion. The argument from design in the first lecture brings up the subject of the introduction of species. Of this, considered "as a question of history, there is no witness on the stand except geology."

"The present condition of geological evidence is undoubtedly in favor of some degree of suddenness—is against infinite gradations. The evidence may be meagre . . . but whether meagre or not, it is all the evidence we have. . . . Now, the evidence of geology to-day is, that species seem to come in suddenly and in full perfection, remain substantially unchanged during the term of their existence, and pass away in full perfection. Other species take their place apparently by substitution, not by transmutation. But you will ask me, 'Do you, then, reject the doctrine of evolution? Do you accept the creation of species directly and without secondary agencies and processes?' I answer, No! Science knows nothing of phenomena which do not take place by secondary causes and processes. She does not deny such occurrence, for true Science is not dogmatic, and she knows full well that, tracing up the phenomena from cause to cause, we must somewhere reach the more direct agency of a First Cause. . . . It is evident that, however species were introduced, whether suddenly or gradually, it is the duty of Science ever to strive to understand the means and processes by which species originated. . . . Now, of the various conceivable secondary causes and processes, by some of which we must believe species originated, by far the most probable is certainly that of evolution from other species."

(We might interpose the remark that the witness on the stand, if subjected to cross-examination by a biologist, might be made to give a good deal of testimony in favor of transmutation rather than substitution.) After referring to different ideas as to the cause or mode of evolution, he concludes that it can make no difference, so far as the argument of design in Nature is concerned, whether there be evolution or not, or whether, in the case of evolution, the change be paroxysmal or uniform. We may infer even that he accepts the idea that "physical and chemical forces are changed into vital force, and vice versa." Physicists incline more readily to this than physiologists; and if what is called vital force be a force in the physicists' sense, then it is almost certainly so. But the illustration on page 275 touches this point only seemingly. It really concerns only the storing and the using of physical force in a living organism. If, for want of a special expression, we continue to use the term vital force to designate that intangible something which directs and governs the accumulation and expenditure of physical force in organisms, then there is as yet no proof and little likelihood that this is correlate with physical force.

"A few words upon the first chapter of Genesis and the Mosaic cosmogony, and I am done," says Prof. Le Conte, and so are we:

"It might be expected by many that, after speaking of schemes of reconciliation, I should give mine also. My Christian friends, these schemes of reconciliation become daily more and more distasteful to me. I have used them in times past; but now the deliberate construction of such schemes seems to me almost like trifling with the words of Scripture and the teachings of Nature. They seem to me almost irreverent, and quite foreign to the true, humble, liberal spirit of Christianity; they are so evidently artificial, so evidently mere ingenious human devices. It seems to me that if we will only regard the two books in the philosophical spirit which I have endeavored to describe, and then simply wait and possess our souls in patience, the questions in dispute will soon adjust themselves as other similar questions have already done."



VIII

WHAT IS DARWINISM? [VIII-1]

The Nation, May 28, 1874)

The question which Dr. Hodge asks he promptly and decisively answers: "What is Darwinism? it is atheism."

Leaving aside all subsidiary and incidental matters, let us consider—1. What the Darwinian doctrine is, and 2. How it is proved to be atheistic. Dr. Hodge's own statement of it cannot be very much bettered:

"His [Darwin's] work on the 'Origin of Species' does not purport to be philosophical. In this aspect it is very different from the cognate works of Mr. Spencer. Darwin does not speculate on the origin of the universe, on the nature of matter or of force. He is simply a naturalist, a careful and laborious observer, skillful in his descriptions, and singularly candid in dealing with the difficulties in the way of his peculiar doctrine. He set before himself a single problem—namely, How are the fauna and flora of our earth to be accounted for? . . . To account for the existence of matter and life, Mr. Darwin admits a Creator. This is done explicitly and repeatedly. . . . He assumes the efficiency of physical causes, showing no disposition to resolve them into mind-force or into the efficiency of the First Cause. . . . He assumes, also, the existence of life in the form of one or more primordial germs. . . . How all living things on earth, including the endless variety of plants and all the diversity of animals, . . . have descended from the primordial animalcule, he thinks, may be accounted for by the operation of the following natural laws, viz.: First, the law of Heredity, or that by which like begets like—the offspring are like the parent. Second, the law of Variation; that is, while the offspring are in all essential characteristics like their immediate progenitor, they nevertheless vary more or less within narrow limits from their parent and from each other. Some of these variations are indifferent, some deteriorations, some improvements—that is, such as enable the plant or animal to exercise its functions to greater advantage. Third, the law of Over-Production. All plants and animals tend to increase in a geometrical ratio, and therefore tend to overrun enormously the means of support. If all the seeds of a plant, all the spawn of a fish, were to arrive at maturity, in a very short time the world could not contain them. Hence, of necessity, arises a struggle for life. Only a few of the myriads born can possibly live. Fourth, here comes in the law of Natural Selection, or the Survival of the Fittest; that is, if any individual of a given species of plant or animal happens to have a slight deviation from the normal type favorable to its success in the struggle for life, it will survive. This variation, by the law of heredity, will be transmitted to its offspring, and by them again to theirs. Soon these favored ones gain the ascendency, and the less favored perish, and the modification becomes established in the species. After a time, another and another of such favorable variations occur, with like results. Thus, very gradually, great changes of structure are introduced, and not only species, but genera, families, and orders, in the vegetable and animal world, are produced" (pp. 26-29).

Now, the truth or the probability of Darwin's hypothesis is not here the question, but only its congruity or incongruity with theism. We need take only one exception to this abstract of it, but that is an important one for the present investigation. It is to the sentence which we have italicized in the earlier part of Dr. Hodge's own statement of what Darwinism is. With it begins our inquiry as to how he proves the doctrine to be atheistic.

First, if we rightly apprehend it, a suggestion of atheism is infused into the premises in a negative form: Mr. Darwin shows no disposition to resolve the efficiency of physical causes into the efficiency of the First Cause. Next (on page 48) comes the positive charge that "Mr. Darwin, although himself a theist," maintains that "the contrivances manifested in the organs of plants and animals . . . are not due to the continued cooperation and control of the divine mind, nor to the original purpose of God in the constitution of the universe." As to the negative statement, it might suffice to recall Dr. Hodge's truthful remark that Darwin "is simply a naturalist," and that "his work on the origin of species does not purport to be philosophical." In physical and physiological treatises, the most religious men rarely think it necessary to postulate the First Cause, nor are they misjudged by the omission. But surely Mr. Darwin does show the disposition which our author denies him, not only by implication in many instances, but most explicitly where one would naturally look for it, namely—at the close of the volume in question: "To my mind, it accords better with what we know of the laws impressed on matter by the Creator," etc. If that does not refer the efficiency of physical causes to the First Cause, what form of words could do so? The positive charge appears to be equally gratuitous. In both Dr. Hodge must have overlooked the beginning as well as the end of the volume which he judges so hardly. Just as mathematicians and physicists, in their systems, are wont to postulate the fundamental and undeniable truths they are concerned with, or what they take for such and require to be taken for granted, so Mr. Darwin postulates, upon the first page of his notable work, and in the words of Whewell and Bishop Butler: 1. The establishment by divine power of general laws, according to which, rather than by insulated interpositions in each particular case, events are brought about in the material world; and 2. That by the word ':natural" is meant "stated, fixed, or settled," by this same power, "since what is natural as much requires and presupposes an intelligent agent to render it so—i.e., to effect it continually or at stated times—as what is supernatural or miraculous does to effect it for once.[VIII-2] So when Mr. Darwin makes such large and free use of "natural as antithetical to supernatural" causes, we are left in no doubt as to the ultimate source which he refers them to. Rather let us say there ought to be no doubt, unless there are other grounds for it to rest upon.

Such ground there must be, or seem to be, to justify or excuse a veteran divine and scholar like Dr. Hodge in his deduction of pure atheism from a system produced by a confessed theist, and based, as we have seen, upon thoroughly orthodox fundamental conceptions. Even if we may not hope to reconcile the difference between the theologian and the naturalist, it may be well to ascertain where their real divergence begins, or ought to begin, and what it amounts to. Seemingly, it is in their proximate, not in their ultimate, principles, as Dr. Hodge insists when he declares that the whole drift of Darwinism is to prove that everything "may be accounted for by the blind operation of natural causes, without any intention, purpose, or cooperation of God." "Why don't he say," cries the theologian, "that the complicated organs of plants and animals are the product of the divine intelligence? If God made them, it makes no difference, so far as the question of design is concerned, how he made them, whether at once or by process of evolution." But, as we have seen, Mr. Darwin does say that, and he over and over implies it when he refers the production of species "to secondary causes," and likens their origination to the origination of individuals; species being series of individuals with greater difference. It is not for the theologian to object that the power which made individual men and other animals, and all the differences which the races of mankind exhibit, through secondary causes, could not have originated congeries of more or less greatly differing individuals through the same causes.

Clearly, then, the difference between the theologian and the naturalist is not fundamental, and evolution may be as profoundly and as particularly theistic as it is increasingly probable. The taint of atheism which, in Dr. Hodge's view, leavens the whole lump, is not inherent in the original grain of Darwinism—in the principles posited—but has somehow been introduced in the subsequent treatment. Possibly, when found, it may be eliminated. Perhaps there is mutual misapprehension growing out of some ambiguity in the use of terms. "Without any intention, purpose, or cooperation of God."- These are sweeping and effectual words. How came they to be applied to natural selection by a divine who professes that God ordained whatsoever cometh to pass? In this wise: "The point to be proved is, that it is the distinctive doctrine of Mr. Darwin that species owe their origin—1. Not to the original intention of the divine mind; 2. Not to special acts of creation calling new forms into existence at certain epochs; 3. Not to the constant and everywhere operative efficiency of God guiding physical causes in the production of intended effects; but 4. To the gradual accumulation of unintended variations of structure and instinct securing some advantage to their subjects." Then Dr. Hodge adduces "Darwin's own testimony," to the purport that natural selection denotes the totality of natural causes and their interactions, physical and physiological, reproduction, variation, birth, struggle, extinction—in short, all that is going on in Nature; that the variations which in this interplay are picked out for survival are not intentionally guided; that "nothing can be more hopeless than the attempt to explain this similarity of pattern in members of the same class by utility or the doctrine of final causes" (which Dr. Hodge takes to be the denial of any such thing as final causes); and that the interactions and processes going on which constitute natural selection may suffice to account for the present diversity of animals and plants (primordial organisms being postulated and time enough given) with all their structures and adaptations—that is, to account for them scientifically, as science accounts for other things.

A good deal may be made of this, but does it sustain the indictment? Moreover, the counts of the indictment may be demurred to. It seems to us that only one of the three points which Darwin is said to deny is really opposed to the fourth, which he is said to maintain, except as concerns the perhaps ambiguous word unintended. Otherwise, the origin of species through the gradual accumulation of variations—i.e., by the addition of a series of small differences—is surely not incongruous with their origin through "the original intention of the divine mind" or through "the constant and everywhere operative efficiency of God."- One or both of these Mr. Darwin (being, as Dr. Hodge says, a theist) must needs hold to in some form or other; wherefore he may be presumed to hold the fourth proposition in such wise as not really to contradict the first or the third. The proper antithesis is with the second proposition only, and the issue comes to this: Have the multitudinous forms of living creatures, past and present, been produced by as many special and independent acts of creation at very numerous epochs? Or have they originated under causes as natural as reproduction and birth, and no more so, by the variation and change of preceding into succeeding species?

Those who accept the latter alternative are evolutionists. And Dr. Hodge fairly allows that their views, although clearly wrong, may be genuinely theistic. Surely they need not become the less so by the discovery or by the conjecture of natural operations through which this diversification and continued adaptation of species to conditions is brought about. Now, Mr. Darwin thinks—and by this he is distinguished. from most evolutionists—that he can assign actual natural causes, adequate to the production of the present out of the preceding state of the animal and vegetable world, and so on backward—thus uniting, not indeed the beginning but the far past with the present in one coherent system of Nature. But in assigning actual natural causes and processes, and applying them to the explanation of the whole case, Mr. Dar-win assumes the obligation of maintaining their general sufficiency—a task from which the numerous advocates and acceptors of evolution on the general concurrence of probabilities and its usefulness as a working hypothesis (with or without much conception of the manner how) are happily free. Having hit upon a modus operandi which all who understand it admit will explain something, and many that it will explain very much, it is to be expected that Mr. Darwin will make the most of it. Doubtless he is far from pretending to know all the causes and operations at work; he has already added some and restricted the range of others; he probably looks for additions to their number and new illustrations of their efficiency; but he is bound to expect them all to fall within the category of what he calls natural selection (a most expansible principle), or to be congruous with it—that is, that they shall be natural causes. Also—and this is the critical point—he is bound to maintain their sufficiency without intervention.

Here, at length, we reach the essential difference between Darwin, as we understand him, and Dr. Hodge. The terms which Darwin sometimes uses, and doubtless some of the ideas they represent, are not such as we should adopt or like to defend; and we may say once for all—aside though it be from the present issue—that, in our opinion, the adequacy of the assigned causes to the explanation of the phenomena has not been made out. But we do not understand him to deny "purpose, intention, or the cooperation of God" in Nature. This would be as gratuitous as unphilosophical, not to say unscientific. When he speaks of this or that particular or phase in the course of events or the procession of organic forms as not intended, he seems to mean not specially and disjunctively intended and not brought about by intervention. Purpose in the whole, as we suppose, is not denied but implied. And when one considers how, under whatever view of the case, the designed and the contingent lie inextricably commingled in this world of ours, past man's disentanglement, and into what metaphysical dilemmas the attempt at unraveling them leads, we cannot greatly blame the naturalist for relegating such problems to the philosopher and the theologian. If charitable, these will place the most favorable construction upon attempts to extend and unify the operation of known secondary causes, this being the proper business of the naturalist and physicist; if wise, they will be careful not to predicate or suggest the absence of intention from what comes about by degrees through the continuous operation of physical causes, even in the organic world, lest, in their endeavor to retain a probable excess of supernaturalism in that realm of Nature, they cut away the grounds for recognizing it at all in inorganic Nature, and so fall into the same condemnation that some of them award to the Darwinian.

Moreover, it is not certain that Mr. Darwin would very much better his case, Dr. Hodge being judge, if he did propound some theory of the nexus of divine causation and natural laws, or even if he explicitly adopted the one or the other of the views which he is charged with rejecting. Either way he might meet a procrustean fate; and, although a saving amount of theism might remain, he would not be sound or comfortable. For, if he predicates "the constant and everywhere operative efficiency of God," he may "lapse into the same doctrine" that the Duke of Argyll and Sir John Herschel "seem inclined to," the latter of whom is blamed for thinking "it but reasonable to regard the force of gravitation as the direct or indirect result of a consciousness or will existing somewhere," and the former for regarding "it unphilosophical 'to think or speak as if the forces of Nature were either independent of or even separate from the Creator's power' ": while if he falls back upon an "original intention of the divine mind," endowing matter with forces which he foresaw and intended should produce such results as these contrivances in Nature, he is told that this banishes God from the world, and is inconsistent with obvious facts. And that because of its implying that "He never interferes to guide the operation of physical causes. We italicize the word, for interference proves to be the keynote of Dr. Hodge's system. Interference with a divinely ordained physical Nature for the accomplishment of natural results! An unorthodox friend has just imparted to us, with much misgiving and solicitude lest he should be thought irreverent, his tentative hypothesis, which is, that even the Creator may be conceived to have improved with time and experience! Never before was this theory so plainly and barely put before us. We were obliged to say that, in principle and by implication, it was not wholly original.

But in such matters, which are far too high for us, no one is justly to be held responsible for the conclusions which another may draw from his principles or assumptions. Dr. Hodge's particular view should be gathered from his own statement of it:

"In the external world there is always and everywhere indisputable evidence of the activity of two kinds of force, the one physical, the other mental. The physical belongs to matter, and is due to the properties with which it has been endowed; the other is the everywhere present and ever-acting mind of God. To the latter are to be referred all the manifestations of design in Nature, and the ordering of events in Providence. This doctrine does not ignore the efficiency of second causes; it simply asserts that God overrules and controls them. Thus the Psalmist says: 'I am fearfully and wonderfully made. My substance was not hid from Thee when I was made in secret, and curiously wrought (or embroidered) in the lower parts of the earth. . . . God makes the grass to grow, and herbs for the children of men.'- He sends rain, frost, and snow. He controls the winds and the waves. He determines the casting of the lot, the flight of an arrow, and the falling of a sparrow."

Far be it from us to object to this mode of conceiving divine causation, although, like the two other theistic conceptions referred to, it has its difficulties, and perhaps the difficulties of both. But, if we understand it, it draws an unusually hard and fast line between causation in organic and inorganic Nature, seems to look for no manifestation of design in the latter except as "God overrules and controls" second causes, and, finally, refers to this overruling and controlling (rather than to a normal action through endowment) all embryonic development, the growth of vegetables, and the like. He even adds, without break or distinction, the sending of rain, frost, and snow, the flight of an arrow, and the falling of a sparrow. Somehow we must have misconceived the bearing of the statement; but so it stands as one of "the three ways," and the right way, of "accounting for contrivances in Nature; the other two being—1. Their reference to the blind operation of natural causes; and, 2. That they were foreseen and purposed by God, who endowed matter with forces which he foresaw and intended should produce such results, but never interferes to guide their operation.

In animadverting upon this latter view, Dr. Hodge brings forward an argument against evolution, with the examination of which our remarks must close:

"Paley, indeed, says that if the construction of a watch be an undeniable evidence of design, it would be a still more wonderful manifestation of skill if a watch could be made to produce other watches, and, it may be added, not only other watches, but all kinds of timepieces, in endless variety. So it has been asked, If a man can make a telescope, why cannot God make a telescope which produces others like itself? This is simply asking whether matter can be made to do the work of mind. The idea involves a contradiction. For a telescope to make a telescope supposes it to select copper and zinc in due proportions, and fuse them into brass; to fashion that brass into inter-entering tubes; to collect and combine the requisite materials for the different kinds of glass needed; to melt them, grind, fashion, and polish them, adjust their densities, focal distances, etc., etc. A man who can believe that brass can do all this might as well believe in God" (pp. 45, 46).

If Dr. Hodge's meaning is, that matter unconstructed cannot do the work of mind, he misses the point altogether; for original construction by an intelligent mind is given in the premises. If he means that the machine cannot originate the power that operates it, this is conceded by all except believers in perpetual motion, and it equally misses the point; for the operating power is given in the case of the watch, and implied in that of the reproductive telescope. But if he means that matter cannot be made to do the work of mind in constructions, machines, or organisms, he is surely wrong. "Sovitur ambulando," vel scribendo; he confuted his argument in the act of writing the sentence. That is just what machines and organisms are for; and a consistent Christian theist should maintain that is what all matter is for. Finally, if, as we freely suppose, he means none of these, he must mean (unless we are much mistaken) that organisms originated by the Almighty Creator could not be endowed with the power of producing similar organisms, or slightly dissimilar organisms, without successive interventions. Then he begs the very question in dispute, and that, too, in the face of the primal command, "Be fruitful and multiply," and its consequences in every natural birth. If the actual facts could be ignored, how nicely the parallel would run! "The idea involves a contradiction." For an animal to make an animal, or a plant to make a plant, supposes it to select carbon, hydrogen, oxygen, and nitrogen, to combine these into cellulose and protoplasm, to join with these some phosphorus, lime, etc., to build them into structures and usefully-adjusted organs. A man who can believe that plants and animals can do this (not, indeed, in the crude way suggested, but in the appointed way) "might as well believe in God." Yes, verily, and so he probably will, in spite of all that atheistical philosophers have to offer, if not harassed and confused by such arguments and statements as these.

There is a long line of gradually-increasing divergence from the ultra-orthodox view of Dr. Hodge through those of such men as Sir William Thomson, Herschel, Argyll, Owen, Mivart, Wallace, and Darwin, down to those of Strauss, Vogt, and Buchner. To strike the line with telling power and good effect, it is necessary to aim at the right place. Excellent as the present volume is in motive and clearly as it shows that Darwinism may bear an atheistic as well as a theistic interpretation, we fear that it will not contribute much to the reconcilement of science and religion.

The length of the analysis of the first book on our list precludes the notices which we intended to take of the three others. They are all the production of men who are both scientific and religious, one of them a celebrated divine and writer unusually versed in natural history. They all look upon theories of evolution either as in the way of being established or as not unlikely to prevail, and they confidently expect to lose thereby no solid ground for theism or religion. Mr. St. Clair, a new writer, in his "Darwinism and Design; or, Creation by Evolution," takes his ground in the following succinct statement of his preface:

"It is being assumed by our scientific guides that the design-argument has been driven out of the field by the doctrine of evolution. It seems to be thought by our theological teachers that the best defense of the faith is to deny evolution in toto, and denounce it as anti-Biblical. My volume endeavors to show that, if evolution be true, all is not lost; but, on the contrary, something is gained: the design-argument remains unshaken, and the wisdom and beneficence of God receive new illustration."

Of his closing remark, that, so far as he knows, the subject has never before been handled in the same way for the same purpose, we will only say that the handling strikes us as mainly sensible rather than as substantially novel. He traverses the whole ground of evolution, from that of the solar system to "the origin of moral species." He is clearly a theistic Darwinian without misgiving, and the arguments for that hypothesis and for its religious aspects obtain from him their most favorable presentation, while he combats the dysteleology of Hackel, Buchner, etc., not, however, with any remarkable strength.

Dr. Winchell, chancellor of the new university at Syracuse, in his volume just issued upon the "Doctrine of Evolution," adopts it in the abstract as "clearly as the law of universal intelligence under which complex results are brought into existence" (whatever that may mean), accepts it practically for the inorganic world as a geologist should, hesitates as to the organic world, and sums up the arguments for the origin of species by diversification unfavorably for the Darwinians, regarding it mainly from the geological side. As some of our zoologists and palaeontologists may have somewhat to say upon this matter, we leave it for their consideration. We are tempted to develop a point which Dr. Winchell incidentally refers to—viz., how very modern the idea of the independent creation and fixity of species is, and how well the old divines got on without it. Dr. Winchell reminds us that St. Augustine and St. Thomas Aquinas were model evolutionists; and, where authority is deferred to, this should count for something.

Mr. Kingsley's eloquent and suggestive "Westminster Sermons," in which he touches here and there upon many of the topics which evolution brings up, has incorporated into the preface a paper which he read in 187i to a meeting of London clergy at Sion College, upon certain problems of natural theology as affected by modern theories in science. We may hereafter have occasion to refer to this volume. Meanwhile, perhaps we may usefully conclude this article with two or three short extracts from it:

"The God who satisfies our conscience ought more or less to satisfy our reason also. To teach that was Butler's mission; and he fulfilled it well. But it is a mission which has to be refulfilled again and again, as human thought changes, and human science develops, For if, in any age or country, the God who seems to be revealed by Nature seems also different from the God who is revealed by the then-popular religion, then that God and the religion which tells of that God will gradually cease to be believed in.

"For the demands of reason—as none knew better than good Bishop Butler—must be and ought to be satisfied. And, therefore, when a popular war arises between the reason of any generation and its theology, then it behooves the ministers of religion to inquire, with all humility and godly fear, on whose side lies the fault; whether the theology which they expound is all that it should be, or whether the reason of those who impugn it is all that it should be."

Pronouncing it to be the duty of the naturalist to find out the how of things, and of the natural theologian to find out the why, Mr. Kingsley continues:

"But if it be said, 'After all, there is no why; the doctrine of evolution, by doing away with the theory of creation, does away with that of final causes,' let us answer boldly, 'Not in the least.' We might accept all that Mr. Darwin, all that Prof. Huxley, all that other most able men have so learnedly and acutely written on physical science, and yet preserve our natural theology on the same basis as that on which Butler and Paley left it. That we should have to develop it I do not deny.

"Let us rather look with calmness, and even with hope and good-will, on these new theories; they surely mark a tendency toward a more, not a less, Scriptural view of Nature.

"Of old it was said by Him, without whom nothing is made, 'My Father worketh hitherto, and I work.' Shall we quarrel with Science if she should show how these words are true? What, in one word, should we have to say but this: 'We know of old that God was so wise that he could make all things; but, behold, he is so much wiser than even that, that he can make all things make themselves?' "



CHARLES DARWIN: A SKETCH

(Nature, June 4, 1874, accompanying a portrait)

Two British naturalists, Robert Brown and Charles Darwin, have, more than any others, impressed their influence upon science in this nineteenth century. Unlike as these men and their works were and are, we may most readily subserve the present purpose in what we are called upon to say of the latter by briefly comparing and contrasting the two.

Robert Brown died sixteen years ago, full of years and scientific honors, and he seems to have finished, several years earlier, all the scientific work that he had undertaken. To the other, Charles Darwin, a fair number of productive years may yet remain, and are earnestly hoped for. Both enjoyed the great advantage of being all their lives long free from exacting professional duties or cares, and so were able in the main to apply themselves to research without distraction and according to their bent. Both, at the beginning of their career, were attached to expeditions of exploration in the southern hemisphere, where they amassed rich stores of observation and materials, and probably struck out, while in the field, some of the best ideas which they subsequently developed. They worked in different fields and upon different methods; only in a single instance, so far as we know, have they handled the same topic; and in this the more penetrating insight of the younger naturalist into an interesting general problem may be appealed to in justification of a comparison which some will deem presumptuous. Be this as it may, there will probably be little dissent from the opinion that the characteristic trait common to the two is an unrivaled scientific sagacity. In this these two naturalists seem to us, each in his way, preeminent. There is a characteristic likeness, too—underlying much difference—in their admirable manner of dealing with facts closely, and at first hand, without the interposition of the formal laws, vague ideal conceptions, or "glittering generalities" which some philosophical naturalists make large use of.

A likeness may also be discerned in the way in which the work or contributions of predecessors and contemporaries are referred to. The brief historical summaries prefixed to many of Mr. Brown's papers are models of judicial conscientiousness. And Mr. Darwin's evident delight at discovering that some one else has "said his good things before him," or has been on the verge of uttering them, seemingly equals that of making the discovery himself. It reminds one of Goethe's insisting that his views in morphology must have been held before him and must be somewhere on record, so obvious did they appear to him.

Considering the quiet and retired lives led by both these men, and the prominent place they are likely to occupy in the history of science, the contrast between them as to contemporary and popular fame is very remarkable. While Mr. Brown was looked up to with the greatest reverence by all the learned botanists, he was scarcely heard of by any one else; and out of botany he was unknown to science except as the discoverer of the Brownian motion of minute particles, which discovery was promulgated in a privately-printed pamphlet that few have ever seen. Although Mr. Darwin had been for twenty years well and widely known for his "Naturalist's Journal," his works on "Coral Islands," on "Volcanic Islands, and especially for his researches on the Barnacles, it was not till about fifteen years ago that his name became popularly famous. Ever since no scientific name has been so widely spoken. Many others have had hypotheses or systems named after them, but no one else that we know of a department of bibliography. The nature of his latest researches accounts for most of the difference, but not for all, The Origin of Species is a fascinating topic, having interests and connections with every branch of science, natural and moral. The investigation of recondite affinities is very dry and special; its questions, processes, and results alike—although in part generally presentable in the shape of morphology—are mainly, like the higher mathematics, unintelligible except to those who make them a subject of serious study. They are especially so when presented in Mr. Brown's manner. Perhaps no naturalist ever recorded the results of his investigations in fewer words and with greater precision than Robert Brown: certainly no one ever took more pains to state nothing beyond the precise point in question. Indeed, we have sometimes fancied that he preferred to enwrap rather than to explain his meaning; to put it into such a form that, unless you follow Solomon's injunction and dig for the wisdom as for hid treasure, you may hardly apprehend it until you have found it all out for yourself, when you will have the satisfaction of perceiving that Mr. Brown not only knew all about it, but had put it upon record. Very different from this is the way in which Mr. Darwin takes his readers into his confidence, freely displays to them the sources of his information, and the working of his mind, and even shares with them all his doubts and misgivings, while in a clear exposition he sets forth the reasons which have guided him to his conclusions. These you may hesitate or decline to adopt, but you feel sure that they have been presented with perfect fairness; and if you think of arguments against them you may be confident that they have all been duly considered before.

The sagacity which characterizes these two naturalists is seen in their success in finding decisive instances, and their sure insight into the meaning of things. As an instance of the latter on Mr. Darwin's part, and a justification of our venture to compare him with the facile princeps botanicorum, we will, in conclusion, allude to the single instance in which they took the same subject in hand. In his papers on the organs and modes of fecundation in Orchideae and Asclepiadeae, Mr. Brown refers more than once to C.K. Sprengel's almost forgotten work, shows how the structure of the flowers in these orders largely requires the agency of insects for their fecundation, and is aware that "in Asclepiadeae . . . the insect so readily passes from one corolla to another that it not unfrequently visits every flower of the umbel." He must also have contemplated the transport of pollen from plant to plant by wind and insects; and we know from another source that he looked upon Sprengel's ideas as far from fantastic. Yet, instead of taking the single forward step which now seems so obvious, he even hazarded the conjecture that the insect-forms of some orchideous flowers are intended to deter rather than to attract insects. And so the explanation of all these and other extraordinary structures, as well as of the arrangement of blossoms in general, and even the very meaning and need of sexual propagation, were left to be supplied by Mr. Darwin. The aphorism "Nature abhors a vacuum" is a characteristic specimen of the science of the middle ages. The aphorism "Nature abhors close fertilization," and the demonstration of the principle, belong to our age, and to Mr. Darwin. To have originated this, and also the principle of natural selection—the truthfulness and importance of which are evident the moment it is apprehended—and to have applied these principles to the system of Nature in such a manner as to make, within a dozen years, a deeper impression upon natural history than has been made since Linnaeus, is ample title for one man's fame.

There is no need of our giving any account or of estimating the importance of such works as the "Origin of Species by means of Natural Selection," the "Variation of Animals and Plants under Domestication," the "Descent of Man, and Selection in Relation to Sex," and the "Expression of the Emotions in Men and Animals"—a series to which we may hope other volumes may in due time be added. We would rather, if space permitted, attempt an analysis of the less known, but not less masterly, subsidiary essays, upon the various arrangements for insuring cross-fertilization in flowers, for the climbing of plants, and the like. These, as we have heard, may before long be reprinted in a volume, and supplemented by some long-pending but still unfinished investigations upon the action of Dionaea and Drosera—a capital subject for Mr. Darwin's handling.

A propos to these papers, which furnish excellent illustrations of it, let us recognize Darwin's great service to natural science in bringing back to it Teleology; so that, instead of Morphology versus Teleology, we shall have Morphology wedded to Teleology. To many, no doubt, evolutionary Teleology comes in such a questionable shape as to seem shorn of all its goodness; but they will think better of it in time, when their ideas become adjusted, and they see what an impetus the new doctrines have given to investigation. They are much mistaken who suppose that Darwinism is only of speculative importance, and perhaps transient interest. In its working applications it has proved to be a new power, eminently practical and fruitful.

And here, again, we are bound to note a striking contrast to Mr. Brown, greatly as we revere his memory. He did far less work than was justly to be expected from him. Mr. Darwin not only points out the road, but labors upon it indefatigably and unceasingly. A most commendable noblesse oblige assures us that he will go on while strength (would we could add health) remains. The vast amount of such work he has already accomplished might overtax the powers of the strongest. That it could have been done at all under constant infirm health is most wonderful.



X

INSECTIVOROUS PLANTS

(The Nation, April 2 and 9, 1874)



That animals should feed upon plants is natural and normal, and the reverse seems impossible. But the adage, "Natura non agit saltatim," has its application even here. It is the naturalist, rather than Nature, that draws hard and fast lines everywhere, and marks out abrupt boundaries where she shades off with gradations. However opposite the parts which animals and vegetables play in the economy of the world as the two opposed kingdoms of organic Nature, it is becoming more and more obvious that they are not only two contiguous kingdoms, but are parts of one whole—antithetical and complementary to each other, indeed; but such "thin partitions do the bounds divide" that no definitions yet framed hold good without exception. This is a world of transition in more senses than is commonly thought; and one of the lessons which the philosophical naturalist learns, or has to learn, is, that differences the most wide and real in the main, and the most essential, may nevertheless be here and there connected or bridged over by gradations. There is a limbo filled with organisms which never rise high enough in the scale to be manifestly either animal or plant, unless it may be said of some of them that they are each in turn and neither long. There are undoubted animals which produce the essential material of vegetable fabric, or build up a part of their structure of it, or elaborate the characteristic leaf-green which, under solar light, assimilates inorganic into organic matter, the most distinguishing function of vegetation. On the other hand, there are plants—microscopic, indeed, but unquestionable—which move spontaneously and freely around and among animals that are fixed and rooted. And, to come without further parley to the matter in hand, while the majority of animals feed directly upon plants, "for 'tis their nature to," there are plants which turn the tables and feed upon them. Some, being parasitic upon living animals, feed insidiously and furtively; these, although really cases in point, are not so extraordinary, and, as they belong to the lower orders, they are not much regarded, except for the harm they do. There are others, and those of the highest orders, which lure or entrap animals in ways which may well excite our special wonder—all the more so since we are now led to conclude that they not only capture but consume their prey.

As respects the two or three most notable instances, the conclusions which have been reached are among the very recent acquisitions of physiological science. Curiously enough, however, now that they are made out, it appears that they were in good part long ago attained, recorded, and mainly forgotten. The earlier observations and surmises shared the common fate of discoveries made before the time, or by those who were not sagacious enough to bring out their full meaning or importance. Vegetable morphology, dimly apprehended by Linnaeus, initiated by Casper Frederick Wolff, and again, independently in successive generations, by Goethe and by De Candolle, offers a parallel instance. The botanists of Goethe's day could not see any sense, advantage, or practical application, to be made of the proposition that the parts of a blossom answer to leaves; and so the study of homologies had long to wait. Until lately it appeared to be of no consequence whatever (except, perhaps, to the insects) whether Drosera and Sarracenia caught flies or not; and even Dionaea excited only unreflecting wonder as a vegetable anomaly. As if there were real anomalies in Nature, and some one plant possessed extraordinary powers denied to all others, and (as was supposed) of no importance to itself!

That most expert of fly-catchers, Dionaea, of which so much has been written and so little known until lately, came very near revealing its secret to Solander and Ellis a hundred years ago, and doubtless to John Bartram, our botanical pioneer, its C probable discoverer, who sent it to Europe. Ellis, in his published letter to Linnaeus, with which the history begins, described the structure and action of the living trap correctly; noticed that the irritability which called forth the quick movement closing the trap, entirely resided in the few small bristles of its upper face; that this whole surface was studded C with glands, which probably secreted a liquid; and that the trap did not open again when an insect was captured, even upon the death of the captive, although it opened very soon when nothing was caught, or when the irritation was caused by a bit of straw, or any such substance. It was Linnaeus who originated the contrary and erroneous statement, which has long prevailed in the books, that the trap reopened when the fatigued captive became quiet, and let it go; as if the plant caught flies in mere play and pastime! Linnaeus also omitted all allusion to a secreted liquid—which was justifiable, as. Ellis does not state that he had actually seen any; and, if he did see it, quite mistook its use, supposing it to be, like the nectar of flowers, a lure for insects, a bait for the trap. Whereas, in fact, the lure, if there be any, must be an odor (although nothing is perceptible to the human olfactories); for the liquid secreted by the glands never appears until the trap has closed upon some insect, and held it at least for some hours a prisoner. Within twenty-four or forty-eight hours this glairy liquid is abundant, bathing and macerating the body of the perished insect. Its analogue is not the nectar of flowers, but the saliva or the gastric juice!

The observations which compel such an inference are re-cent, and the substance of them may be briefly stated. The late Rev. Dr. M. A. Curtis (by whose death, two years ago, we lost one of our best botanists, and the master in his especial line, mycology), forty years and more ago resided at Wilmington, North Carolina, in the midst of the only district to which the Dionaea is native; and he published, in 1834, in the first volume of the "Journal of the Boston Society of Natural History," by far the best account of this singular plant which had then appeared. He remarks that "the little prisoner is not crushed and suddenly destroyed, as is sometimes supposed," for he had often liberated "captive flies and spiders, which sped away as fast as fear or joy could hasten them." But he neglected to state, although he must have noticed the fact, that the two sides of the trap, at first concave to the contained insect, at length flatten and close down firmly upon the prey, exerting no inconsiderable pressure, and insuring the death of any soft-bodied insect, if it had not already succumbed to the confinement and salivation. This last Dr. Curtis noticed, and first discerned its import, although he hesitated to pronounce upon its universality. That the captured insects were in some way "made subservient to the nourishment of the plant" had been conjectured from the first. Dr. Curtis "at times (and he might have always at the proper time) found them enveloped in a fluid of mucilaginous consistence, which seems to act as a solvent, the insects being more or less consumed in it." This was verified and the digestive character of the liquid well-nigh demonstrated six or seven years ago by Mr. Canby, of Wilmington, Delaware, who, upon a visit to the sister-town of North Carolina, and afterward at his home, followed up Dr. Curtis's suggestions with some capital observations and experiments. These were published at Philadelphia in the tenth volume of Meehan's Gardeners' Monthly, August, i868; but they do not appear to have attracted the attention which they merited.

The points which Mr. Canby made out are, that this fluid is always poured out around the captured insect in due time, "if the leaf is in good condition and the prey suitable;" that it comes from the leaf itself, and not from the decomposing insect (for, when the trap caught a plum-curculio, the fluid was poured out while he was still alive, though very weak, and endeavoring, ineffectively, to eat his way out); that bits of raw beef, although sometimes rejected after a while, were generally acted upon in the same manner—i.e., closed down upon tightly, salvered with the liquid, dissolved mainly, and absorbed; so that, in fine, the fluid may well be said to be analogous to the gastric juice of animals, dissolving the prey and rendering it fit for absorption by the leaf. Many leaves remain inactive or slowly die away after one meal; others reopen for a second and perhaps even a third capture, and are at least capable of digesting a second meal.

Before Mr. Canby's experiments had been made, we were aware that a similar series had been made in England by Mr. Darwin, with the same results, and with a small but highly-curious additional one—namely, that the fluid secreted in the trap of Dionaea, like the gastric juice, has an acid reaction. Having begun to mention unpublished results (too long allowed to remain so), it may be well, under the circumstances, to refer to a still more remarkable experiment by the same most sagacious investigator. By a prick with a sharp lancet at a certain point, he has been able to paralyze one-half of the leaf-trap, so that it remained motionless under the stimulus to which the other half responded. Such high and sensitive organization entails corresponding ailments. Mr. Canby tells us that he gave to one of his Dionaea-subjects a fatal dyspepsia by feeding it with cheese; and under Mr. Darwin's hands another suffers from paraplegia.

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