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DARWIN'S CENTURY -- EVOLUTION AND THE MEN WHO DISCOVERED IT |
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Chapter IV: Progressionism and Evolution
I. Geological Prophecy A bone, to Cuvier, was never just a bone, because it told, in its curvatures and varied processes, the story of an organized being whose every other bone and organ could be expected to be in harmonious proportion and accord with the solitary fragment. Thus, within a certain degree, a claw should ordinarily disclose a particular type of tooth, or a tooth the necessary nature of a shoulder blade. A landscape, to James Hutton, was not a given thing, shaped once and forgotten, but rather a page from a continuing biography of the planet. The scene had been written by frost and a light wind that blew for ages, by the hidden touch of subterranean fires, by a plant that grew and held a little patch of soil from being carried away by a stream. Whatever else it was also, this landscape was natural. It had not been wrought by convulsive and mythical events or by the hand of a wrathful Divinity. Instead, it was a part of the long intricate interplay between the forces that waste away the land and the forces that produce uplift and renewal. A countryside is above all a biography, the only visible biography left by time, Similarly a stratum, to William Smith, was not a thick layer of indifferent rock, but a ladder descending into the. unknown darkness of the past. Caught and preserved like insects in amber, there were, at every rung of that ladder, animals, to use Smith's own phrase, "materially different from those now in existence." As we survey these tremendous contributions to human knowledge, contributions to which we have grown so accustomed by long familiarity that the genius of the men who made them escapes us, we wonder what ingredient was still lacking to convince the general public that organic, as well as stellar, evolution was a reality. We are, however, if we think in this manner, still unconsciously projecting back upon the first decade of the nineteenth century accumulations of information which did not then exist. Let us look a little more closely at this situation. In 1788 Hutton's first and most compactly literate account of his discovery had been published. It had come at a time when the German geologist Werner had been at the height of his teaching popularity and when the public, by its own Christian tradition, preferred stories of a great Flood. Hutton had grasped the significance of fossils, but unfortunately he came too early to quite realize the fact of animal difference and extinction on the scale science was later to discover. Extinction, by its nature, could not be inferred. It had to be found out by empirical means. As a consequence, though Hutton saw illimitable vistas of time and the natural forces which worked to mold the surface of the planet, his uniformitarianism is total. He did not visualize organic change; he was content with having perceived the main outlines of the way in which the world machine persisted and renewed itself. About life· he asked few questions. There is thus an oriental flavor of eternal changelessness in his system. All things pass only to come round again in the great year, in the march of waves that are forever similar. A system of this sort does not, by itself, attract followers in· a culture dedicated to a unique drama in the sense that the Christian world was so dedicated. William Smith, shortly after Hutton's death, in feeling his way down through the strata began to recognize change, but it was, on the whole, petty molluscan change. Smith was working mainly in marine beds and was concerned with tracing similar strata over considerable areas of England. The ideal organisms for this purpose are marine molluscs and similar creatures, which appear in constant profusion. Vertebrate fossils tend to be too sparsely distributed to be useful. In addition, as we have seen, Smith was a practical engineer, not a student of philosophical anatomy like Cuvier. In later writings he speaks of vertebrate fossils but it is largely because of the work of Cuvier with which he had become acquainted. Though there is a genuine rise in public interest which heightened after Cuvier's brilliant exploits in vertebrate paleontology, of which he is the recognized founder, we can, if we look sharply, see pretty clearly that the true continuity of evolution has not quite been attained. The reason lies in the fact that, though between the achievements of Smith and Cuvier the public had finally become excited and convinced that a past world existed, it was not, in actuality, impressed by the continuity of that past. It had accepted the sharply demarcated and successive organic worlds of Smith and Cuvier while, at the same time, it had rejected the continuous and permeating time flow of Hutton. It took the superimposed strata, just as Smith had taken them, to be as distinctly defined in time as they appeared in the rock formations. Each stratum with an organic content differing in a major way from one above or below represented a distinct creation which was then, after a variable period of time, destroyed by convulsive upheavals and floods over the surface of the globe. Instead of the smooth flow of life through long eons in which certain forms became extinct and others evolved and changed, the public was really enjoying, not a motion picture of the planet's past, but a series of still photographs extracted from their context. The knowledge of the layman had been deepened and broadened, but both he and most contemporary scientists still preferred at least some aspects of a cosmology with which they had been familiar since childhood. The genuine unity of organic design which could be traced from the present into these worlds of the past was assumed to be an immaterial, spiritual connection emanating from the designer of the universe. It was not believed to represent in the least a physical connection. When Cuvier succeeded in demonstrating a progressive aspect, particularly to land life, this was quickly transformed in the minds of the more traditional thinkers into an increasingly complex prologue leading on toward man who in the words of one of these thinkers was "foreknown and prefigured from the beginning." One can note that this type of "progressionism," as it was termed, has some of the qualities of the Scale of Being still lingering about it. For one thing the progressivist doctrine is man-centered. Man is believed to be the goal of the process and everything points in his direction or prophesies his appearance. At the same time we may note that the progressionist doctrine clearly demonstrates the fact that it was possible to temporalize the Chain of Being and extend it into the past without making it a truly evolutionary philosophy. Here, instead, we have a succession of organic worlds, each terminated by catastrophic and probably supernaturally induced geological disturbances. The unity of design which connects the flora and fauna of these worlds is, as one of the leading proponents of progressionism states. "nothing like parental descent." He makes it quite clear that the link is "of a higher and immaterial nature." [1] Spiritual evolution, it might be said, thus precedes a belief in actual physical change. Here, in the pre-Darwinian portion of the nineteenth century, we encounter what is really a combination of traditional Christianity overlaid by a wash of German romantic philosophy. Elements of the new science and the new discoveries are being fitted into what is regarded as the "foreordained design of the Creator." Much of this thought derives from late eighteenth-century German romantic writers, but in England the Christian element becomes pronounced. As Gode-von Aesch has pointed out, a whole philosophical school in Germany came to regard the world "as a gigantic system of hieroglyphics, as the language of God or the book of nature." [2] Interesting in this connection is the fact that Karl Kielmeyer, Cuvier's early friend and anatomy instructor, seems to have been the earliest formulizer (1793) of the biogenetic law which was regarded by the romantic philosophers as the dawn of a new era in science. [3] It will be remembered that the biogenetic law, which in the post-Darwinian period is widely associated with the name of Ernst Haeckel, expresses the idea that there is a parallelism between the stages of embryonic growth in the individual and the succession of fossil stages in the phylogeny of the species. In its earlier pre-evolutionary idealistic expression among the German philosophers it reflected the conception that man was a microcosm or reflection of the rest of the organic kingdom and that his embryonic development reflected the fact that "animals are merely foetal stages of man." [4] This conception can be found reflected in some of the racial thinking even of post-Darwinian days in which it is assumed that the Caucasian, as the highest type of man, reflects in embryonic or infantile stages the other lower races. This German philosophy is, of course, closely allied to, and in some degree is developed from, reflections upon the Scale of Being. [5] When, in the English progressionist philosophy, a revised scale of being was actually projected into the past, it was inevitable, under the circumstances, that there should emerge a system of "geological prophecy." The fossils were true hieroglyphs, signs from earlier ages as to God's intention and design. There is, moreover, a continuing unilineal trend to the whole scheme which ignores Cuvier's divergent classes. Everything points prophetically toward man. The fossil footprints of Chirotherium, an extinct reptile, had a vaguely human appearance. They are read as "mute prophecies of the coming being." [6] The philosopher James McCosh and his collaborator George Dickie argued that bipedal fossil footprints of birds (actually dinosaurs) were a sign of human appearance "in a subsequent and still distant epoch." [7] It is obvious, as we find statements of this kind in the writings of eminent biologists, that this transcendental emphasis among the progressionists was bound to inhibit in some degree the understanding of ecology, divergence and adaptation. Instead, attention is concentrated upon the "prophetic scroll" of geology. The books of Hugh Miller went through numerous editions. Certain of his ideas were drawn from Louis Agassiz who survived to combat Darwin and remain to the end a convinced adherent of the progressionist point of view. Many passages reveal that this type of anthropocentric concentration made the assumption inevitable that with the appearance of man the geological story was complete. Thus as late as 1866 Louis Agassiz expressed himself as follows: "Coming to the noble form of Man we find the brain so organized that the anterior portion covers and protects all the rest so completely that nothing is seen outside, and the brain stands vertically poised on the summit of the backbone. Beyond this there is no further progress, showing that man has reached the highest development of the plan upon which his structure was laid." [8] In another earlier volume he stated even more explicitly that "by anatomical evidence" man is "the last term of a series, beyond which there is no material progress possible in accordance with the plan upon which the whole animal kingdom is constructed...." [9] The italics are mine. They are intended to draw attention to the typical transcendental implication of a prefigured order, and the emphasis placed upon man as the creature for whom, or toward whom, the entire creation had labored. The passage is, basically, merely another repetition of Oken's remark that animals are foetal stages of man. It should now be apparent that, in spite of certain interesting ideas carried into British biology from German sources, what had emerged was still not a true evolutionary system of thought. Rather it represents a type of biological supernaturalism linked with a similarly supernatural geology. It remained to be seen what the renewed attempt to introduce uniformitarian conceptions into this system would bring forth. II. Sir Charles Lyell and the Re-emergence of Uniformitarianism James Hutton, as we have seen, was one of the first men to ignore the flood hypothesis in a full-fledged and comprehensive study of the mechanics of physical geology. [10] He had argued that the continents were built from the ruins of more ancient land surfaces and that these past worlds had been continuous and unbroken in their history with the eras which had succeeded them. Not many were attracted by the vast impersonal spectacle he presented and his followers were few. Among them, however, was John Playfair who, in 1802, undertook to present to the public in his Illustrations of the Huttonian Theory of the Earth a lucid and less prolix account of his friend's work. There is no doubt that this book -- a very elegantly written treatise -- did something to keep Hutton's name faintly alive in the thirty years during which catastrophism was the reigning geological doctrine. The conservative English reaction to the French Revolution, however, submerged Playfair almost as effectively as his predecessor. Then, at a time when Cuvier was at the height of his fame, and the leading geologists of both England and France were catastrophists, a young unknown man, Charles Lyell (1797-1875), published a book, Principles of Geology, which was destined to destroy the reigning geological doctrine and introduce unlimited time and the play of natural forces once more into geology. Lyell must be accorded the secure distinction, not alone of altering the course of geological thought, but of having been the single greatest influence in the life of Charles Darwin. Moreover, he introduced Lamarck's theories to the British reading public and, although he opposed them, he gave Lamarck a fair dispassionate hearing. Lyell had originally been trained for the law. He knew how to marshal the facts of an argument, to weigh evidence and to present it well. [11] Stylistically his writing was distinguished. His book was widely read not only by professional geologists but by the cultivated public whose curiosity about the secrets of the earth was growing. Without the public revision of attitude on the subject of time and natural forces working over Inconceivably long intervals Darwinism would have had little chance of acceptance. Moreover, it is unlikely that without the influence of Lyell's book Darwin would have conceived or put forth his theory. Curiously, though Lyell won in the geological field a victory similar to the one Darwin was later to achieve in biology, he did not become an evolutionist until his last years, although today it seems to us that evolution was the normal consequence of the system he presented. It remained, instead, for Darwin to demonstrate that the successive organic worlds of the progressionists were actually moving with the steady invisibility of a clock hand. The astronomer Halley in 1717 had demonstrated our solar system to be adrift in some great star- swirl rather than anchored securely at a fixed spot in space. Darwin was about to reveal that, not man alone, but the whole world of life was similarly unfixed in position. Rising, falling, evolving, changing, it was anything but the stable system visualized by the reigning philosophy of the eighteenth century, or the directed progression toward man envisaged by the majority of thinkers in the early nineteenth century. Before turning to Darwin, however, it is necessary to examine the nature of Sir Charles Lyell's biological thinking. He was eleven years older than Darwin and his great work was achieved at an earlier age. Darwin read the first edition of the Principles of Geology while on the voyage of the Beagle and became Lyell's devoted admirer upon his return. In fact, as early as 1836 Darwin wrote to a friend, "Amongst the great scientific men, no one has been nearly so friendly and kind as Lyell." [12] Darwin never made any secret of his debt to Lyell -- he dedicated the Journal to him-but there are few, nevertheless, who realize the extent of this relationship. Geology and biology, in spite of certain mutual interests, are now far more divergent and specialized than they were in 1830. As a consequence, Sir Charles Lyell's biological writings tend to remain unread because they are contained in an old textbook of geology and his geological successors are inclined to occupy themselves historically only with Sir Charles's contributions to geology. In the course of time a legend has arisen that Darwin drew his geological uniformitarianism from Lyell, but that his knowledge of biological matters is derived from other sources. No one would deny that Darwin was an inveterate reader and observer, but an examination of Lyell's early writings reveals that in the Principles he came very close to Darwin's position. Consequently, one can scarcely resist the observation that the Origin could almost literally have been written out of Lyell's book, once the guiding motif of natural selection had been conceived. Lyell circled again and again about the leading idea that eluded him, but perhaps the fact that he was older than Darwin by more than a decade produced in him, both by background and temperament, a greater aversion toward the last inevitable step. His long reluctance to declare himself, which at times irritated Darwin, is suggestive of the hesitation which may have partially blocked his insight upon the matters which he discussed so thoroughly and with such toleration and objectivity in the Principles. [13] Later we shall examine this problem at more length. In Darwin's first brief sketch of his theory, written in 1842, there is a phrase about Augustin de Candolle's "war of nature." [14] This reference to the French botanist also occurs in the Origin. Now it is often said that Darwin took the phrase "struggle for existence» from Malthus, and Malthus is accorded a high place by Darwin in leading him to his great discovery. Malthus, in Darwin's essay of 1842, is mentioned along with De Candolle, but not in such a manner as to suggest that Darwin was unaware of other writings upon the struggle for existence. Instead, Malthus's doctrine of geometric increase seems to have caught his fancy as graphically indicating the great pressure of life against its resources. When glancing at the reference to De Candolle I noted that Darwin gave no direct source and remembering Darwin's own admission that he did not read French with facility, I was curious as to where he had found this reference. Knowing that Darwin had occasionally drawn upon Lyell's Principles for facts, I re-examined my copy of the third edition (1834). In the third volume (p. 35) I came upon the quote from De Candolle, the source again unindicated. "All the plants of a given country; remarked the French botanist, "are at war with one another." Lyell then quotes De Candolle at some length upon the struggle for living space until "the more prolific gradually made themselves masters of the ground...." There can be no doubt then as to where the De Candolle reference was secured. Indeed, Darwin himself in the first edition of the Origin remarks that "the elder De Candolle and Lyell have largely ... shown that all organic beings are exposed to severe competition." [15] Lyell, in another place, after speaking of un" healthy plants being the first to be destroyed and choked out by more vigorous individuals, uses the phrase which was afterwards to become world famous, "the struggle for existence." [16] Tradition has often maintained that Darwin drew it direct from Malthus, but of this there is no evidence. Lyell himself in after years reiterated to the biologist Haeckel his early treatment of certain of the ideas which went into natural selection and once more gives credit to DeCandolle for the idea of the struggle for existence. [17] "Most of the zoologists," he added a little wearily (this was 1868), "forget that anything was written between the time of Lamarck and the publication of our friend's Origin of Species." We have, of course, already seen that the idea of struggle, and even selection within varietal limits, is far older than De Candolle, but it is equally clear that Darwin probably drew more heavily upon Lyell in regard to this subject than upon Malthus. Lyell's work, directly concerned with animals as it is, contains much extensive ecological discussion. He speaks of the changes that can ensue from the introduction of a new species in a given region. He recognizes that "the changes caused indirectly would ramify through all classes of the living creation, and be almost endless." [18] There is clear evidence that Lyell actually anticipated Darwin in the recognition of ecological change which could promote extinction. The intricate relations between species, including the unconscious effects wrought by man, were all carefully considered and elaborated, Lyell was not prepared to recognize the creative aspect of the changes he observed in nature, yet he saw clearly that disturbances of natural balance might easily lead to extinctions and readjustments of the fauna over wide areas. Such a succession of species did not have to wait upon geological convulsions but were a constant product of natural selection! Ironically enough, Sir Charles Lyell had fully recognized the negative aspects of the principle and had passed beyond Lamarck in recognizing its part in the elimination of species. His failure lay in his inability to grasp the principle in its full creative role. He was still under the Linnaean spell that the amount of variation which could be produced was limited. There is much in Lyell's career that served as an outright model for Darwin's activities. In addition, Lyell accumulated in his book stores of information from some of the sources we have previously discussed. They were thus conveniently summarized and brought to the direct attention of Darwin, and Darwin's co-worker Wallace, by the hand of a man directly interested in the same problems which confronted them. In fact, one might well say he composed and set forth for them the problem which they eventually solved. He advocated a geological continuity based on Huttonian principles, but built upon much more extended geological information that had accumulated since the days of Hutton and Playfair. In successfully overthrowing by degrees the old catastrophic doctrine, he was inevitably destroying also the precise, serried, and advancing worlds of the progressive creationists. Instead, it became apparent, in the light of Lyell's careful examination of the struggle for existence and the interlinked web of nature, that the succession of species had always been going on throughout past time and was even now continuing. No item was too small for its significance to escape him as it might relate to the demonstration of the persistence of natural forces similar to those active upon the globe today. He drew from Buckland's investigation of the eyes of trilobites the observation that "the ocean must then have been transparent as it is now; and must have given a passage to the rays of light, and so with the atmosphere; and this leads us to conclude that the Sun existed then as now and to a great variety of other inferences." [19] He was one of the first to investigate fossil rain marks, "the drops of which resembled in their average size those which now fall from the clouds." He argued on the basis of this evidence "that the atmosphere of one of the remotest periods known in geology corresponded in density with that now investing the globe." [20] It was this type of long, careful mustering of evidence which led to the final fading of the catastrophic doctrines. As one impressed reviewer put the matter as early as 1835, "the concession of an unlimited period for the working of the existing powers of nature has permitted us to dispense with the comets, deluges and other prodigies which were once brought forward, ad libitum, to solve every difficulty in the path of the speculating geologist." [21] It was from Lyell that Darwin drew his now well-known argument as to the imperfection of the geological record. It was to Lyell, as late as the writing of the Descent of Man (1871), that Darwin had recourse in the attempt to explain how a comparatively weak-bodied primate could have survived until his cultural development made him a match for the formidable carnivores of the primitive world. Here is Lyell's statement: "... for if a philosopher is pleased to indulge in conjectures on this subject [i.e., the birthplace of humanity], why should he not assign, as the original seat of man, some one of those large islands within the tropics, which are as free from wild beasts as Van Dieman's Land or Australia? Here man may have remained for a period peculiar to a single isle, just as some of the large anthropomorphous species are now limited to one island within the tropics. In such a situation, the new born race might have lived in security, though far more helpless than the New Holland savages, and might have found abundance of vegetable food." [22] A similar expression, save for the added element of natural selection, is to be found in the closing paragraph o. Chapter II of the Descent of Man. Darwin had been attacked critically by the Duke of Argyll, and it is interesting that in this period of his mature scholarship Darwin still sought his old friend's speculations when he found himself in a tight spot. Although such evidences of Lyell's influence upon Darwin as I have given here could be multiplied, their general bearing is plain: Lyell, far more extensively than Buffon, possessed in 1830 all of the basic information necessary to have arrived at Darwin's hypothesis but did not. Granted some emotional aversion to a family connection with Lamarck's orang (a relationship to which he jokingly referred), Lyell was, nevertheless, a cool, objective reasoner, as well informed biologically as he was geologically. Studies of his letters have led to a few accusations that he equivocated, that he assumed a conservative pose in public and speculated privately upon the possible mutability of species. [23] I think that this charge of timid vacillation is in some degree unjust to the man who marshaled the evidence and took the stand which eventually destroyed the catastrophic doctrine which, in the words of a contemporary historian of science, William Whewell, "held almost undisputed sway in geological circles." [24] It is true his work was later to become a conservative classic, but at the time it was launched Lyell stood courageously alone as much as Darwin did when the Origin was given to the press. Lyell cannot, therefore, be easily called, in spite of a pleasant uncontroversial temperament, a truckler to public opinion. As a matter of fact, even his biological observations received laudatory attention shortly after the publication of the second volume of the Principles -- that volume which was so to excite Darwin when it reached him in South America. "Nothing," maintained Whewell, who reviewed it in the conservative Quarterly Review, [25] "can be more striking than the picture given by our author of the mutual wars of the different tribes of plants and animals, their struggles for food, their powers of diffusion ... and the wide and sweeping changes which these phenomena have produced and are producing in the face of animated nature." Whewell dwells upon the "ingenious reasoning" by which Lyell accounts for extinctions. "The author," he says admiringly, "urges that when new species multiplying widely, and requiring large supplies of food, are introduced into a country, the older tenants of the soil must necessarily be reduced by want, and some classes must be destroyed." This is just how close to evolution Lyell was in 1830 and this is the way in which certain, though not all, of his ideas were being received by a leading scholar in a widely read review. What then were the inhibiting factors which contributed to drawing Lyell's attention away from a subject to which he had devoted much space in his great book? I think they lie, much more than has been realized, in the philosophical background of uniformitarianism and, curiously enough, in the progressionism which, at first glance, seems to have been moving in an evolutionary direction. The situation is a complex one, demanding considerable analysis. Moreover, it has been further obscured through the unconscious simplification of motives activating those, including Lyell and Huxley, who survived the progressionist period to become full-fledged Darwinists. There is always a desire, after such a great intellectual triumph as Darwinism represented, to submerge the account of one's past hesitations and to appear to have been a disciple who, from the first, had never doubted the direction events were to take. In 1868, when Darwin was riding the full wave of his fame, Lyell wrote to the German biologist Ernst Haeckel acknowledging the gift of the latter's latest book. In a discussion of some of the historical background of the evolutionary philosophy and his own contribution to it, Lyell remarks, and the remark in and of itself is honest enough, "I had certainly prepared the way...." [26] The intriguing thing about this statement, however, and a few others of comparable character, is the fact that right up to the time, almost, of the publication of the Origin of Species, Lyell was advocating, though with no great success and not by any really extended publication, a doctrine which he himself once termed "non-progressionism." In the commotion attendant upon the publication of the Origin, and in the ensuing debates, non-progressionism died quietly, never to be resurrected by its author. Lyell, as is evident from his later modest claims to have been one of Darwin's predecessors, was content to let his ill-starred theory perish without being acknowledged by its author. Yet it is this theory which was actually expressed in his Anniversary Address given before the Geological Society of London in 1851. The speech is of particular interest because facts in this address were once referred to by Lyell in connection with his claims to having promoted the way for Darwin. Again he is not wrong in detail, but he chose not to be wholly candid about this-forgotten episode. With the death of progressionism -- and progressionism began to die more rapidly after the glacial theory was developed at the hands of Agassiz and others in the forties [27] -- non-progressionism ceased to have meaning. Since it is one of the obscurer and shorter-lived episodes in nineteenth-century thought it has not been investigated nor its meaning in relation to larger events examined, This doctrine, however, irrational though it may now seem, is perfectly consistent and logical for a Huttonian and a uniformitarian to have advocated. It is no aberration on the part of Sir Charles Lyell. It is, instead, the logical outcome of pure uniformitarianism when that system is kept fully divested of progressionist elements. Evolution, by contrast, is a system which contains material derived from both philosophies. It is a hybrid, a product, really, of two distinct lines of thought which had to merge to become completely successful. All this the world has forgotten and Lyell for very human reasons helped in the forgetting. It is now necessary to examine non-pro- gressionism and the intellectual atmosphere out of which it arose. III. Non-progressionism We have observed, in our discussion of James Hutton, that he had seen the world as a self-adjusting, self-renovating engine, surviving through illimitable vistas of time. Cosmological speculation, theories of earth formation, of which there had been many before him, he viewed with distrust. They were, he felt, essentially speculative and unverifiable. He wished to confine geology to its proper province -- the earth -- and to the facts which could be elicited from her formations and deposits. It was essential to the regularity of Hutton's system that there be no mysterious and supernatural, or unaccountable, powers at work in the earth. The erosive forces shaping the surface of the planet were to be seen as those at work around us constantly in the shape of winds and frost and running water, along with the somewhat more mysterious but natural forces of heat in the earth's interior. Life did not particularly occupy his attention -- he saw it merely as extending into the indefinite past. There was as yet no sure evidence of vast extinctions or the progressive advancement of living forms. By the time Lyell came to write the Principles of Geology, he was, though drawn to the uniformitarian philosophy, presented with a somewhat different situation than had confronted Hutton in the 1780s. There were evidences pointing to extinction of animal forms, to the past existence of unknown animals, and, above all, there existed in the transcendental, man-centered progressionism of the catastrophists a philosophy which was the very antithesis of the Huttonian approach. Progressionism may very well be regarded today as a long step toward evolution. Looked at in another light, from Lyell's position in the 1830s, it could be viewed, like catastrophism itself, as a retreat from scientific principles and an introduction of supernaturalism into geology. Lyell, in defending the uniformitarian geology, could scarcely at the same time be expected to embrace progressionism which, as we have seen, is really the biological equivalent of catastrophism. As a consequence, from the very beginning Lyell's philosophical position was somewhat ambiguous if not contradictory. In spite of his great victory over the "convulsionists" he was never entirely happy with the situation in which he found himself. He had come upon the scene too late to ignore the accumulated information upon organic change, but was philosophically committed to secondary causes and the reign of natural law. What was easy for the progressionist to account for by special creation and divine edict was a constant embarrassment to the man whose whole work had been opposed to epochs of extinction and re-creations of fauna. As a later writer has observed of this period, "The aim of naturalists seemed to be to create a world as unlike that of today as it was possible to have it." [28] Lyell, when he challenged the validity of catastrophism, was inevitably confronted with a far more unanswerable problem. Unlike Hutton he had to account in uniformitarian terms, not alone for change in the inorganic world, but in the world of life as well. If he was forced to admit supernaturalism in the successive creations of life, then his geological opponents could readily say, and they did say: "When we find that such events as the first placing of man upon the earth, and the successive creation of vast numbers of genera and species, are proved to have occurred within assignable geological epochs, it seems to us most natural to suppose, that mechanical operations also have taken place, as different from what now goes on in the inorganic world as the facts just mentioned are from what we trace in organic nature." [29] Lyell, in other words, was being challenged either to explain the mysterious changes in the world of life or accept the fact that the planet also has been shaped by unknown forces. It was a shrewd and formidable challenge. Lacking the Darwinian principle only one recourse was possible. In taking this way out Lyell was not able to remain wholly consistent and his thinking on the subject wavered from time to time. In essence, however, he clung to a slightly modified Huttonian position: he accepted time as being boundless as space and he denied, admittedly in a rather cautious fashion, that major organic changes could be proved. As part of his geological treatment of the subject he extended and elaborated Hutton's work upon erosion, but where Hutton had contented himself with physical geology, Lyell called paleontology to his aid. He pointed out that the unity of plan, which could be traced from living forms back into the past, itself bespoke an unbroken continuity and connection. He strove successfully to show that the catastrophic discontinuities supposed to be world-wide in extent were frequently local and that animal forms claimed for a single catastrophic interval could be traced, in many instances, straight though successive strata, thus raising serious questions as to the total obliteration of successive faunas. He made use of the argument from the imperfection of the geological record to claim that we do not have sufficient evidence to prove the type of biological progression which so many writers demanded. "The only negative fact," Lyell contended in the Principles, "remaining in support of the doctrine of the imperfect development of the higher orders ... in remote ages, is the absence of birds and mammalia. The former are generally wanting in deposits of all ages." Land mammals could not be expected in oceanic deposits. For the more remote ages, therefore, there was "scarcely any means of obtaining an insight into the zoology of the then existing continents." [30] Man, Lyell was forced rather unwillingly to admit, did seem to be a recent introduction and an exception to his system. Lyell was not so foolish as to deny that there had been organic change of a sort on the planet. It is here that his system and his writings, scattered over some twenty or more years, are not always consistent. Essentially, however, his position, which, rather than weakening, was being more strongly asserted by its author at mid-century, can be summarized about as follows. He recognized that faunas altered and changed, but by using inferences drawn from peculiarities of modem distribution he seems, like Cuvier before him, [31] to suggest that many of the differences between one age and an- other are not the result of newly generated species. Instead, they may represent influxes from other areas, influxes made possible by shifts in the position of land and sea along with climatic alterations. Thus he pointed out that even in the nineteenth century one could find a dominant marsupial fauna in Australia, a reptilian fauna in the Galapagos, and a bird fauna in New Zealand. If we knew of these facts only from geological evidences we might claim some kind of progressive succession which actually represents only geographical distinctions. In like manner there may have been periods in the past when reptiles, for example, dominated wider areas than today without there being a succession of forms "governed by any law of progressive development." [32] Similar arguments were used in the field of paleobotany. By Lyell's time it was not, of course, possible to deny the extinction of certain forms of life, but the great geologist was intent upon discrediting the notion of progressive succession which constituted a threat to his uniformitarian geology. Nor, incidentally, can he be labeled as totally wrong. When the older catastrophic notions began to give way because it was being discovered that the supposedly separate creations overlapped, what was more natural at first than a reaction like Lyell's? Animals whose time of origin was supposedly known began to be found further back in time than had been anticipated. Even the most clearly established, recent form of all -- man -- began to be eyed with more suspicion. Lyell dismissed the doctrine of successive development as untrue. "By the creation of species," he said, "I simply mean the beginning of a new series of organic phenomena, such as we usually understand by the term 'species:" As to how these species came into existence he offered no conjecture, though he hinted that he did not believe "the renovating power" totally suspended. It can now be seen, glancing 'back at the intellectual climate of Lyell's period, that a great deal of his energy, thought, and effort had to be devoted to the support of the Huttonian conception of time and natural process. The one idea of what we might call "evolutionary'" advance which stood in popular favor was basically Imbued with a supernatural aura which Lyell felt obliged to reject. This led him, ironically, into a position where he was in some danger of rejecting organic change at the same time that he tried to account for it by natural means. His position was, from the first, an uneasy and ambivalent one. It forced him into extended investigations which were of great value to Darwin and Wallace, for he had concentrated upon the forces making for organic change in order to explain these naturally. His comments upon animal distribution, the struggle for existence, extinction, and related topics were, on the whole, judicious and painstaking. Without them it may well be that neither Darwin nor Wallace would have stumbled upon the final secret. That this position was not purely an idiosyncrasy of Lyell's can be seen from Huxley's Anniversary Address of 1861 before the Geological Society of London. [33] In it he took a firm stand against the progressionist doctrine. There is, he admits like Lyell, "abundant evidence of variation -- none of what is ordinarily understood as progression." There is a sort of oscillation principle in some of this writing, a willingness to admit the fact that the great classes of life have thrown off variable forms in different ages and that these forms may become extinct and new ones arise by means unknown. The system, in principle, however, is too uniform for modem taste. It is almost like the self-correcting aberrations that occur in the cosmic systems of the eighteenth-century astronomers. This attitude stems naturally from the eighteenth-century influence of Hutton. The uniformitarians were, on the whole, disinclined to countenance the intrusion of strange or unknown forces into the universe. They eschewed final causes and all aspects of world creation, feeling like their master Hutton that such problems were confusing and beyond human reach. The uniformitarian school, in other words, is essentially a revolt against the Christian conception of time as limited and containing historic direction, with supernatural intervention constantly immanent. Rather this philosophy involves the idea of the Newtonian machine, self- sustaining and forever operating on the same principles. For this school to have introduced progressive biological change into its schema would, as we have seen, been an abandonment of its own principles. In terms of nineteenth-century science it would have smacked of the supernatural, of forces not susceptible to investigation and hence suspect. The only thing that the uniformitarian hypothesis did lend in the direction of evolutionary thought was continuity of action. Lyell augmented this Huttonian observation by attempts to account naturally for extinction, faunal shifts, and similar topics. He retained, however, a bias toward cyclic rather than Indefinitely progressive change. Here, however, he is not always consistent. His position, and the facts, made total consistency impossible. By contrast, the philosophy of catastrophism was frankly supernatural in essence, and progressive. The world was not regarded as always shaped by the forces of today, and the biological record in the rocks was read as progressive though its material continuity is interrupted. There is a mixture of both change and Platonism Involved in this point of view. Life is prophetic from its first appearance and points on to man. Cosmology held no terrors for the catastrophist. Thus progressionism was better prepared, in a sense, to accept the mysterious origins of life and the apparition of new forms in the rocks than the uniformitarian who wanted to believe only in forces he could see and interpret in terms of existing knowledge. [34] The final victory of uniformitarian geology over catastrophism, and the fact that Lyell, its leading proponent, became a Darwinian, has led to the unconscious assumption that uniformitarianism nourished the evolutionary hypothesis. Actually, however, this can be observed to be only a partial truth. Uniformitarianism was, in some respects, rigid and uncompromising. It was wary of anything which could be regarded as an upward trend in the organic world although it was soon obvious that the fact of such a trend, irrespective of its explanation, could not be evaded. Lyell felt pressed by this problem and it led to some. of his ambiguous and uneasy evolutionary remarks, which, to use the words of his great pupil Darwin out of context, are master wrigglings" rather than prophetic insights. We may thus say briefly that evolution, to a very considerable extent, arose out of an amalgamation or compromise which partook largely of progressionism, but drew the important principle of continuity and adaptive response largely from uniformitarianism. Darwin, by an astute application of Malthusian selection, supplied the observable "natural" principle demanded by the uniformitarians and this relaxed their fears of supernaturalism. Progressionism and uniformitarianism in their extreme forms began to fade from men's minds. What emerged -- Darwinism, developmentalism, evolutionism -- was the intellectual offspring of two distinct schools of biological thought. _______________ Notes: 1. Hugh Miller, The Testimony of the Rocks, Edinburgh, 1869, p. 192. 2. Alexander Gode-von Aesch, Natural Science in German Romanticism, Columbia University Press, 1941, p. 219. 3. Ibid., p. 121. 4. Oken cited by Gode-von Aesch, op. cit., p. 122. For a detailed discussion of the German transcendental school of biology one should consult E. S. Russell's excellent work Form and Function, New York, 1917. 5. Russell, op. cit., p. 214. 6. Miller, op. cit., p. 193. 7. Typical Forms and Special Ends in Creation, New York, 1857, p. 330. 8. The Structure of Animal Life, New York, 1866, pp. 108-9. 9. An Essay in Classification, London, 1859, pp. 34-35. 10. Among the propositions which Buffon had been forced to recant by the Sorbonne was the view that the surface features of the earth were due to secondary causes which, in time, would destroy them and produce others of similar character. 11. Professor C. F. A. Pantin in speaking of the Origin of Species says that its style reminds him of Lyell's Principles of Geology "to which unquestionably it was indebted." Lyell's early training as a barrister, he goes on to say, has certainly benefited mankind. "Darwin's Theory and the Causes of its Acceptance," The School Science Review, June, 1951, p. 313. 12. Life and Letters of Charles Darwin, ed. by Francis Darwin, London: John Murray, 1888, Vol. 1, p. 277. 13. Lyell himself once remarked, "You may well believe that it cost me a struggle to renounce my old creed." Life, Letters and Journals of Sir Charles Lyell, ed. by Mrs. Katherine Lyell, London: John Murray, 1881, Vol. 2, p. 376. 14. Foundations of the Origin of Species, ed. by Francis Darwin, Cambridge University Press, 1909. p. 7. 15. O, p. 53. 16. PG, 1834, Vol. 2, p. 391. 17. LLL. Vol. 2, p. 436. 18. PG, Vol. 3, p. 52. 19. Sir Charles Lyell, Eight Lectures on Geology, New York, 1842, pp. 41-42. 20. Sir Charles Lyell, "On Fossil Rain-Marks of the Recent, Triassic, and Carboniferous Periods," Quarterly Journal of the Geological Society of London, 1851, Vol. 7, p. 247. 21. Anonymous, "Lyell's Principles of Geology," Quarterly Review, 1835, Vol. 53. p. 410. The paper is unsigned but attributable to William Whewell. 22. PG, Vol. 3. pp. 17-18. 23. Darwin's pseudonymous biographer, Geoffrey West, has taken this point of view. See Charles Darwin, A Portrait, Yale University Press, 1938, pp. 103, 123. 24. Quarterly Review, 1835. Vol. 53. p. 407. 25. 1832, Vol. 47, pp. 118, 120. 26. LLL, Vol. 2, p. 436. See also LLD, Vol. 2, p. 190. 27. Ice advances explained away the glacial erratics which had been previously used to bolster the position of the catastrophists. 28. Science, 1883, Vol. 1. p. 69. 29. Quarterly Review, 1832, Vol. 47. p. 126. 30. PG, Vol. 2, pp. 396-97. 31. The Idea Is implied In Hutton (1788) but was not developed. 32. Anonymous, "Sir Charles Lyell on Progressive Development," Edinburgh New Philosophical Journal, 1852, Vol. 52, pp. 358-59. 33. Frequently reprinted among his essays under the title "Geological Contemporaneity and Persistent Types of Life." 34. It should be noted, of course, that It was possible, at least theoretically, to be a catastrophist without inclining toward supernatural forces. The bent of the school, however, runs otherwise.
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