DARWIN'S CENTURY -- EVOLUTION AND THE MEN WHO DISCOVERED IT
Chapter I: The Age of Discovery
I. The Voyagers
It has been remarked by historians that the discovery of the world by the great voyagers, and particularly their passage across the western seas, had made a tremendous impact upon the thought of Europe In the sixteenth and seventeenth centuries. There was nothing recondite or obscure about the discoveries of the captains. The unlettered as well as the cultivated were stirred by new facts and speculations to an Increasing sophistication which spread by way of the ports and the tales of homing sailors. This broadening intellectual experience was shared by all western Europeans and it aided tremendously in ushering in the dawning age of science.
As an indirect consequence of this adventure the theory of evolution, vast in its implications as a new continent, was really, in essence, glimpsed through the fogs and sea wrack penetrated by the master mariners. Moreover, and most appropriately, it was to be a voyager- naturalist, Charles Darwin, later on in the nineteenth century, who would finally establish its reality. Like the fabulous western isles the idea would be coasted at first through dangerous intellectual waters. It would be termed a phantom, a figment of man's restless imagination. It would be labeled like a sea monster "blasphemous," "illusory," and "godless." Finally it would lie there under the lifting fogwisps which had so long .obscured the human vision, a country of wraiths and changelings among whom was to be accounted man himself. Time such as humanity had never dreamed before lay across that world. It was a land where water wore away the shapes of mountains, and the great bones and carapaces of vanished beasts lay hoar and rime-frosted in deep crevices and canyons.
This wild landscape was, by the twentieth century, utterly to possess the human mind. Christian thought had long contemplated eternity but it had been the shadowless, changeless eternity of God. Earthly time had been seen by comparison as the brief drama of the Fall and Redemption, the lowly world of Nature merely the stage setting for a morality play. "Time we may comprehend; wrote Sir Thomas Browne in the Religio Medici, "'tis but five days elder than ourselves, and hath the same Horoscope with the World." 
The tight little medieval domain, with its ark full of known animals and its Biblically accounted for humanity, was soon to find itself theologically at grips with a whole series of unexpected problems. Ostensibly the voyagers went to seek lands and riches but they saw with human eyes and they returned with observations which stimulated the curiosity of savants and stay-at-home thinkers. "We carry with us the wonders we seek without us: there is all Africa and her prodigies in us" defends Sir Thomas Browne again, and this is true. Nevertheless, the curious marvels over which he exclaims are, to a marked extent, the product of that subversive and elusive thought which has begun to reach even the sedentary scholar In his garden. Intruding into the devout world of Thomas Browne comes "another secret not contained In the Scripture, which is more hard to comprehend ... and that is ... how America abounded with Beasts of prey and noxious Animals, yet contained not In it that necessary Creature a Horse, is very strange. By what passage those, not only Birds, but dangerous and unwelcome Beasts, came over; how there be creatures there, which are not found in this Triple Continent; all which must needs be strange unto us, that hold but one Ark, and that the Creatures began their progress from the Mountains of Ararat."
Obviously the solution to this mystery lies in evolutionary radiation and organic change. The seventeenth century does not provide an appropriate answer but it is clear that the voyagers, bringing home accounts of East Indian orangutans and Cape Hottentots, along with strange seeds from the Americas and reports of the doings of Red Indians, are providing a new and mysterious universe for examination. Old explanations no longer hold, old philosophies are fraying at the edges.
Long before the eighteenth-century naturalists began to grope toward an explanation of the odd facts of animal distribution and variation, speculations such as the one I have just quoted from Sir Thomas Browne were destined to become widespread in European thought. It would not be long until all the Ingredients necessary to devise a working theory of evolution would be present In the literature. The emergence. of a true evolutionary philosophy would then wait only upon the abatement of religious prejudice and the appearance of a synthesizing mind capable of taking a great body of diverse data and relating it within the confines of a single abstraction.
First, however, as so often happens in the history of a scientific hypothesis, a series of compromises were bound to be attempted between older and more recent modes of thought. It is obvious that to fully understand the evolution of the evolutionary principle itself, one must examine the preceding intellectual climate out of which it arose. The various streams of thought which, pursuing separate channels, eventually merged as one in the mind of Charles Darwin have had an intricate and autonomous existence which is not fully revealed by a mere recital of dates and names. It is my hope, in the pages that follow, to recapture from the fossil world of documents some glimpses of the living shape of thought as it flows, mutates, and transforms itself from age to age. The task has about it some of the same fascination which comes to those who pursue the related forms of animals downward through the ever lengthening vistas of the past.
To some degree it is inevitable that we should share with the paleontologist the vexation of lost documents and disconnected phylogenies. For this reason I have not attempted to treat of the speculative evolutionary philosophy of early Greek writers, nor to pursue the distantly related alchemical thinking of the Arabs. What is known of these matters has been adequately treated in the works of other authors. In this book we shall be concerned only with the last three centuries which, as I have intimated, afford us our major clues to the nature and development of the evolutionary philosophy. My treatment of the subject does not purport to be a history of biology in general. It is directed only toward the main theme and, in two chapters, is concerned particularly with problems which arose in the field of human evolution.
If I have touched lightly upon certain familiar names such as Thomas Huxley, it has not been out of neglect or ignorance, but simply because their story was not germane to the particular line of thought being followed in this work. At the risk of being deliberate and pedestrian, I have chosen to follow the intellectual currents which produced the major evolutionary synthesis and, by patient and detailed analysis, to perceive from whence and under what conditions \:hat complex of ideas known as Darwinism has emerged. I am under no illusion that the story has been fully told. I will be satisfied if there is added to the general store of our knowledge a glimpse of the ingredients which crystallized into a new thought pattern which lies at the root of Western thinking. The period after nineteen hundred is really a separate problem in itself, complex, many-sided and demanding lengthy individual treatment. To that period, as time may permit, I contemplate devoting a second volume.
II. The Two Ladders and the Scale of Being
There are two main ways by which the transmutations of organic substance, or, as we would say today, the evolution of life, can be approached: through the living world around us or by means of the record of the fossil past which is preserved, albeit fragmentarily, within the sedimentary rocks of the planet. There is, in other words, a ladder backward into time which involves the careful anatomical comparison of existing forms of life at various levels of complexity, and the use of such information in attempting to work out the major physiological and anatomical advances in the history of life. The other ladder by which we descend into the past is that of paleontology itself, the analysis, again by comparative anatomy, of the organic remains of all those once living orders which have left bones or impressions of their bodies encased in the substance of ancient land surfaces or sea bottoms. There are, of course, accessory approaches to the problem to be derived from such studies as animal and plant distributions and from embryology, that science which concerns itself with the development of the single individual from the time of his conception. Essentially, however, all of these methods are in some degree dependent upon our two major techniques: the analysis of the living organism In order that we may extrapolate Into the past, and the use of the fossilized organism to determine the actual life of the past Thus we are able In some degree to check the findings of comparative anatomy as it philosophizes from the living animal alone.
As we survey the course of scientific history it would appear Inevitable that the present world would have given man his first clues to the history of life. Yet it is interesting to observe that only the existence In the West of a certain type of theological philosophy caused men to look upon the world around them In a way, or In a frame, that would prepare the Western mind for the final acceptance of evolution. Strange though it may sound, it was a combination of Judeo-Greek ideas, amalgamated within the medieval church itself, which were to form part of the foundation out of which finally arose, In the eighteenth and nineteenth centuries, one of the greatest scientific achievements of all time: the recovery of the lost history of life, and the demonstration of its total interrelatedness. This achievement, however, waited upon the transformation of a static conception of nature into a dynamic one. It was just this leaven which the voyagers supplied with their unheard-of animals, and apes that were scarcely distinguishable from savage men.
Widespread In the literature of the seventeenth and eighteenth centuries, and easily traceable Into earlier periods, is the theological doctrine known variously as the Scala Naturae, Chain of Being, echelle des etre, Ladder of Perfection, and by other similar titles. Before the doctrine and its history were subjected to careful analysis In Professor A. O. Lovejoy's masterly volume The Great Chain of Being (1942), several well-intentioned but historically naive scholars, coming upon expressions of this philosophy In eighteenth-century literature, had mistakenly multiplied the number of Darwin's forerunners. It behooves us to examine this philosophy carefully, for if we think of our first approach, the living ladder into the past, this philosophy will be found to equate quite satisfactorily with the Scale of Being concept. There can be little doubt that the rise of comparative anatomy is inextricably linked to the history of the Chain of Being concept with its gradations of complexity in living forms. In making this observation, however, we have to keep in mind one salient fact. Strange though it may sound to a modem evolutionist this gradation of organisms implied nothing in the way of phylogenetic relationship. Equally it implied nothing in the way of evolutionary transformations and it specifically denied the possibility that any organism could become extinct. The whole scheme was as rigidly fixed as the medieval social world itself. Indeed it is to some degree a powerful mental projection of that world.
"There is in this Universe a Stair," continues Browne, "rising not disorderly, or in confusion, but with a comely method and proportion." And since the Scale of Nature runs from minerals by insensible degrees upward through the lower forms of life to man, and beyond him to purely spiritual existences like the angels, ourselves, compounded of both dust and spirit, become "that great and true Amphibium, whose nature is disposed to live ... in divided and distinguished worlds." We exist, in short, in both the material and spiritual universes. In this respect Homo duplex, as he was sometimes called, occupies a place on the scale of life as a link between the animal and spiritual natures. Man suffers from this division and it contributes to his ofttimes confused and contradictory behavior.
If, however, this serried array of living forms does not denote a physical phylogenetic connection, what can it be said to represent? It is just here that we enter upon the very real differences which exist between the recognition of grades of complexity in nature and the assumption that a lower level of complexity evolves physically into that of a higher -- that an ape, by way of illustration, may evolve into a man. The scholars of the eighteenth century recognized quite well that the ape stood next to man on the Scale of Nature, but they did not find this spectacle as appalling as a nineteenth-century audience listening to Thomas Huxley. There was a very simple reason for this: The Scala Naturae in its pure form asserts the immutability of species. The entire chain of life is assumed to have been created in its present order when God by creative fiat brought the universe out of chaos.
As we remarked earlier the scale is static. Creation is not considered as still in progress. Thus the resemblances between living things are not the result of descent with modification but rather are the product of the uniformity and continuity of the divine act. Since the world was assumed by theologians and scientists alike to be only a few thousand years old, the question of evolution could arise only with the greatest difficulty. There was literally not time enough for such a creation. Theologically it was also held that animal species could not become extinct. By and large, men eyed askance the notion that a whole order of life could disappear. Such piecemeal disappearances from the Scale of Nature seemed to threaten the confidence reposed in divine providence.
As time went on, evidences for the past existence of organisms no longer to be found on the planet began to be brought forward but were received with obvious reluctance. Few wished to believe the reports and their reception was not encouraging. Since knowledge of some parts of the world was scant, even well into the eighteenth century, one favorite resort was to accept the disappearance of certain forms of life in Europe but with the proviso that the creatures probably still survived in remote areas of the earth.
It was a convenient evasion of a question which had theological overtones. For just this reason, however, the often mentioned reports of mammoths surviving into colonial times in interior North America have to be viewed with great skepticism. The intellectual climate of the times promoted and encouraged such accounts. Always the creatures lay just a little farther on, first in the Virginia woods, or in Labrador, then deeper into the interior or "across the lakes." They were heard bellowing in the woods, or seen grazing on the plains of South America. In no case, however, is the documentation satisfactory, nor were hides or tusks from recent beasts shipped home to adorn the cabinets of eager scientists. With the acceptance of the idea of total and successive extinctions of past faunas at the dawn of the nineteenth century the sporadic reports of living mammoths or mastodons began to fade. It must also be remembered in this connection that until the 'great age of the world and its successive strata were grasped, no great antiquity could be attributed even to fossil bones.
It remains a curious episode in the history of science that the Scale of Nature doctrine which denied extinction should at the same time have encouraged the comparative anatomical observations which would eventually lead to the discovery of extinction. Even more important, the idea of phylogenetic relationship along the scale of life would emerge almost simultaneously. The attention which perfectly orthodox thinkers were encouraged to give to the ascending ladder of being, their eagerness to trace every degree of continuous relationship in the productions of the divine being, their zealous efforts to show that the apparent missing links in the scale could be found, enormously stimulated the study of taxonomy and variation.
All that the Chain of Being actually needed to become a full-fledged evolutionary theory was the introduction into it of the conception of time in vast quantities added to mutability of form. It demanded, in other words, a universe not made but being made continuously. It is ironic and intriguing that the fixed hierarchical order in biology began to pass almost contemporaneously with the disappearance of the feudal social scale in the storms of the French Revolution. It was France, whose social system was dissolving, that produced the first modern evolutionists. As we look back upon the long reign of the Scale of Being, whose effects, as we shall later see, persisted well into the nineteenth century, we may observe that the seed of evolution lay buried in this traditional metaphysic which indeed prepared the Western mind for its acceptance. "Thus disguised and protected," writes Lois Whitney, "did the hypothesis of evolution have, as it were, a happy seed time, a period in which to germinate and take root, before the orthodox world scented the danger." 
III. The Baconian and Humanistic Traditions in Natural History
The documents of the early naturalists contain scattered observations generally left undeveloped by their originators. One finds, for example, that it was apparently Sir Francis Bacon who first proposed the idea that the peoples of Holarctica, that is, the northern circumpolar land mass, tended to dominate the southern areas of the planet because they had greater ruggedness and endurance than the people of the southern continents. Whether he ever realized it or not, Charles Darwin made use of precisely this same idea, extended on a broader evolutionary scale, to account for the frequent dominance of northern faunas over southern ones at such times as faunal movements radiated in a north-south direction. This has appeared often to be the case in Tertiary and Quaternary times, northward movements from southern faunal centers seeming, with occasional exceptions, to be less successful.
Here are Bacon's own words from his essay "Of Vicissitudes of Things" written most probably in the last decade of the sixteenth century: "But North and South are fixed: And it hath seldome or never been seene, that the farre Southern People have invaded the Northern, but contrariwise. Whereby it is manifest, that the Northern Tract of the World, is in Nature the more Martiall Region: Be it in respect of the Stars of that Hemisphere; Or of the great Continents that are upon the North, whereas the South Part, for ought that is known, is al. most all Sea; Or (which is most apparent) of the Cold of the Northern Parts, which is that which without Aid of Discipline, doth make the Bodies hardest, and the Courages warmest."
Charles Darwin's interpretation, unchanged from the first edition of the Origin to the last, runs as follows: "I suspect that this preponderant migration from north to south is due to the greater extent of land in the north, and to the northern forms having existed in their own homes in greater numbers, and having consequently been advanced through natural selection and competition to a higher stage of perfection, or dominating power, than the southern forms,"  Though this. is said in a context referring to plant life Darwin makes it very clear in later editions that "the same principles apply to the distribution of terrestrial animals and of marine productions," My intention in aligning these two quotations is not, of course, to derive Darwin's biology from Bacon, but to give at least a glimpse of the antiquity of some of the ideas which needed only to be developed and elaborated in order to take a legitimate place in an evolutionary system of thought. Darwin, as a matter of fact, is far more apt to have taken his idea of "polar dominance" from Lyell's Principles of Geology upon which he drew so much. Lyell argued that the cooling state of the earth in recent geo logical times had stimulated a faunal movement in a north-south direction. 
Ideas of this character-ideas without which an evolutionary theory could never have been constructed-are surprisingly numerous in the literature of the seventeenth century. In many instances they are confined to a paragraph or so, as when the astronomer Christian Huygens in his posthumous work The Celestial Worlds Discovered (1698) recognizes the principles of comparative anatomy. He is arguing for the likelihood of life basically resembling ours on other planets and, to make his point, he draws on the analogy of the new world of America, "Who doubts; he contends, "but that God, if he had pleased, might have made the animals in America and other distant countries nothing like ours? Yet we see he has not done it."
"They have indeed some difference in Shape; he goes on, "but even in this Variety there is an Agreement, an exact Correspondence in Figure and Shape, the same ways of Growth and new Productions, and of continuing their own kind. Their Animals have Feet and Wings like ours, and like ours have Hearts, Lungs, Guts, and the Parts serving to Generation.... 'Tis plain then that Nature has not exhibited that Variety in her Works that she could...." Pondering at some length over these morphological similarities which yet contain a shade of difference -- "an Argument of no small Weight that is fetched from Relation and Likeness" -- we can see Huygens's thought revolving, all unknowingly, about a mystery which will be resolved only in the Darwinian maxim "descent with modification."
If we return a moment to Sir Thomas Browne whose felicity of phrase so well reveals the cultivated thinking of his era, we find him speaking of two books, two revelations, which have contributed to his religious life. "Besides that written one of God," he speaks of another, Nature, "that Universal and publick Manuscript, that lies expans'd unto the eyes of all: those that never saw him in the one, have discovered him in the other. There was never anything ugly or misshapen, but the Chaos; he continues thoughtfully as he runs a contemplative eye over a toad, a bear, and an elephant "All things are artificial," and "Nature is the art of God." Here, superlatively expressed, is the tolerant and inquiring spirit which, arising out of a growing interest in the natural world, was eventually to soften the harsh orthodoxy of those who regarded the earth and its products as vile. In this view is incorporated that argument from design which reaches a culmination in the Bridgewater Treatises of the early nineteenth century. In Browne's work, however, this philosophy lacks the narrow anthropocentrism which it acquired at the hands of less gifted and more orthodox thinkers.
In English thought since the time of Bacon two in influences have been paramount in the study of living nature. One stems directly from the purely scientific and experimental approach of Bacon, the subjection of nature "to the question," in the grim phrase of the Lord Chancellor. The other more gracious, humane tradition descends through John Ray and Gilbert White, two parson-naturalists, to the literary observers of later centuries, men such as Thoreau and Hudson. The two streams have at times mingled, influenced and affected each other but they have remained in some degree apart in method and in outlook. Though Darwin is generally claimed by the scientists, it is worthy of note that he did not remain uninfluenced by, the literary tradition in natural history which is so strong in England. He was a devoted reader of Gilbert White and once commented to his friend Jenyns that it was a pity foreign periodicals showed no interest in this type of anecdotal natural history.  There is little doubt that he received the initial stimulus for his earthworm studies from The Natural History of Selborne (1789) and his debt may be even more extensive. It has not been generally remarked by students of Darwin's Variation of Animals and Plants under Domestication that in 1780 White expressed to his friend Pennant the opinion that the small blue rock pigeon is the ancestral prototype of the domestic varieties of this bird. This hypothesis, greatly elaborated by Darwin as part of his marshaling of evidence bearing upon evolution, occurs in both the Origin and in his later treatise upon domestication. Darwin does not claim originality in respect to his views on the subject and we may well suspect that White's comments did not go unstudied when Darwin was combing the biological literature for proofs of his theory.
It is to the labors of innumerable scholars of White's "observational abilities that we owe the accumulation of detail which led eventually to the erection of the major evolutionary hypothesis. Note that in the case we have been discussing there is already a clear recognition of organic variation within the domain of a single species. One hundred and fifty years earlier Browne, musing over his own palm prints, had discovered that "which I could never read of nor discover in another." The wonder of individual variation had struck him. "Even in things alike there is diversity." Genetics was as yet unborn but its essence is contained within that simple statement.
An earlier and greater parson-naturalist than White,  John Ray (1627-1705), was a contemporary of Browne. Ray was one of the leading naturalists of the seventeenth century and not least among those whose attempts to class sify and describe the living world were a necessary prelude to the discovery of organic evolution. 
An orderly and classified arrangement of life was an absolute necessity before the investigation of evolution, or even its recognition, could take place. Before life and its changes and transmutations can be pursued into the past, the orders of complexity in the living world must be thoroughly grasped. Comparative anatomy must have reached a point of development sufficient to permit the scientist to distinguish a living animal from one no longer in existence. Moreover, the naturalist must be able to recognize affinity and relationship in the midst of difference. He must be able to observe the likeness which reveals the interrelatedness of life across the gulf of time and yet, equally, pointing to distinctions of detail, the student must be able to say "here change is evident." Knowledge of this degree of sophistication could not come in a day. As the great Swedish taxonomist Linnaeus was to remark later, "The first step of science is to know one thing from another. This knowledge consists in their specific distinctions; but in order that it may be fixed and permanent distinct names must be given to different things, and those names must be recorded and remembered."  John Ray was a modem in his search for a natural system of classification based upon clear structural affinities.
In this respect Ray anticipated and influenced Linnaeus. Moreover, in his emphasis upon "natural system," in his concern with behavior, he had perhaps a more far-ranging philosophic mind than his successor. He not only helped make possible the Systema Naturae of Linnaeus: he was also the forerunner of Gilbert White, of Paley's Natural Theology and finally of the Origin of Species. The Wisdom of God Manifested in the Works of Creation (1691), his best-known and most popular work, created a pattern which, in its attempt to expound the mysterious laws of life and co-ordinate a wide range of phenomena, is still to be found in innumerable books of both a vitalistic and mechanistic nature right down to our own day.
In the last decade of his life, writing to his friend Lhwyd (1695) over some puzzling fern leaf impressions in stone, he hesitates and confesses that such an exact similarity to real plants seems hardly ascribable to chemical accident. Sincere Christian that he was, there is a touch of pathos in his penetrating vision of what the full acceptance of the real meaning of fossils might mean to the devout. The consequences, Ray saw, might well result in challenging the whole Christian cosmology as it was then understood. Fossils might raise questions as to the antiquity of the world and the duration of species. "Whatever may be said for ye Antiquity of the Earth itself and bodies lodged in it," Ray argued, retreating from the abyss, "ye race of mankind is new."  Nevertheless, he broods a little. He had premonitions that would return to haunt Linnaeus long years later.
Linnaeus shares, with the Comte de Buffon, whom we will consider in the next chapter, the distinction of being a phenomenon rather than a man. This achievement, though it demands great energies and unusual ability, is, in reality, dependent upon the psychological attitudes of a given period. The genius must receive extraordinary support and co-operation in intellectual circles. Linnaeus wrote and flourished in a time when the educated public had become fascinated with the word, the delight in sheer naming. The natural world, the world of the voyagers, was being described, oriented, classified -- and suddenly, for no clearly apparent reason, the public wanted to participate in the process. It wanted to send packets of seeds to its hero, Carl Linnaeus. It wanted to hear him pronounce a new rolling Latin name to which, if one were lucky, one might find one's own attached.
He was the inspiration of young men like Peter Kalm who, as one of his American correspondents wrote to Linnaeus, "has undergone such great difficulties in travelling through a great part of this vast forest, and risked such dangers in his person from its savage inhabitants, that ... his zeal cannot be sufficiently applauded."  Another enthusiast writing from the island of Madeira complains that "all the rare plants grow either on high cliffs near the sea or in horrible deep chasms."  Ships fail to make port; precious plants wither in the months of endless voyaging; there are other dangers. "Dr. John Mitchel," reports Linnaeus in 1746, "is returned from Virginia, where he has been closely occupied for six years in collecting plants; but he was plundered in his voyage home by Spanish pirates, to the great misfortune of Botany,"  In London the Quaker merchant Peter Collinson confided prophetically to the master, "We are very fond of all branches of Natural History; they sell the best of any books in England."  In the great parks of English noblemen plants from around the world were beginning to grow, plants and even occasionally animals which had been collected in the gloom of the American forests and nursed homeward in the cabins of rough sea captains. It was at last the full if early morning of the scientific age. All over the world the night was passing and strange beautiful plants were opening their flowers to the sun. In that time of unfolding beauty the purpose of science was still largely to name and marvel. In that art there was none to surpass Carolus Linnaeus.
In 1707, two years after the aged and infirm John Ray had died at Black Notley, Linnaeus was born in southern Sweden. It was a time of marked English influence in Sweden. Many young men of family journeyed to London, and English philosophy and science exerted great influence upon Swedish culture. Linnaeus, being in modest circumstances, took his medical degree in Holland, where he came in contact with the great Dutch scientist Hermann Boerhaave and launched the first edition of his best-known work, the Systema Naturae, in 1735. In 1736 he visited England and made a solid acquaintanceship in learned circles. From that time onward his prestige in English science was enormous -- a genuine mass phenomenon. As his recent biographer Knut Hagberg remarks, "The greatest distinction an Englishman -- whether amateur or academically qualified -- could dream of at that time was to be mentioned in one of Linnaeus's works, and to that end they sent him innumerable suggestions for the alteration of the classification of species in Systema Naturae."  That the personal charm of the man contributed to the regard in which he was held, there can be no doubt. When we consider, however, that his influence reached into the New World among men who had never seen him and, moreover, that this adulation persisted into his old age so that upon his death in 1778 he was borne to the tomb like a king, it is evident that he had become in some strange manner the symbol of science itself. Not least among the ironies of Linnaeus's career is the fact that he whose taxonomy had, before his death, come to stand for the sure fixity and eternal order of relationships in the world of life should have entertained discreet doubts as to its reality.
Because Linnaeus became known to the English reader as a taxonomist, as the creator of a system of ordered relationships, much of the poetry of his nature -- his Whitmanesque love of the incredible variety of life -- has escaped attention. Few of his great heaps of manuscripts and only some of his letters have been translated. It was basically this poetic hunger of the mind to experience personally every leaf, flower, and bird that could be encompassed in a single life which explains his gigantic labors. He was the naming genius par excellence, a new Adam in the world's great garden, drunk with the utter wonder of creation. This is revealed in miscellaneous notes and jottings where, like a poet, he catalogues. for the rich joy of the words. "American falcons, divers kinds of parrots, pheasants, peacocks, guinea fowl, American capercaillie, Indian hens, swans, many different kinds of ducks and geese, gulls and other web-footed birds, snipe, American crossbills, sparrows of divers kinds, turtle doves, and other doves together with various other species of birds, with whose cries the garden resounded." 
Similarly it is the poet brooding over time and destiny who writes this eulogy for the great botanists: "For even if knowledge of the true and original Tree of Life, which could have postponed the arrival of old age, is lost, the plants nevertheless remain and renew their flowers, and with gratitude enduring through the years they shall always exhale the sweet memory of your names, and make them more lasting than marble, so that they will outlive those of kings and heroes. For riches vanish, the most stately mansions fall into decay, the most prolific families die out sooner or later: the mightiest states and the most flourishing kingdoms may be overthrown: but the whole of nature must be obliterated before the genera of plants disappear and he be forgotten who held the torch aloft in botany." 
"The plants remain and renew their flowers" -- in those simple words is the nostalgia and melancholy of a man who, even at the height of his success, knew with preternatural insight that, as he himself wrote, "fate is always against great things." Perhaps he felt, in those lines written to a far-off captain bringing him seeds, a premonition of the future -- his own lapse into senile dementia and the blurring of the sharply precise and ordered system of taxonomy which had been his vision when he wrote the Systema Naturae.
It was Linnaeus's fate to stand on the threshold of the modern world, in fact to spend the better part of his life constructing that threshold, that entrance, to new vistas he would never see. As we have seen, the same year that he went to Holland to complete his medical degree Linnaeus published the first edition of the Systema Naturae. At that time it was only a summary digest of the extensive treatise it was later to become. Coincident with his rise to scientific fame and fortune, he succeeded in later editions of the Systema and other works in imposing the now well-known system of binominal nomenclature upon the scientific public. The naming of plants and animals before Linnaeus had been confused, unsystematic, and verbose. This is not to say that Linnaeus had not been influenced by his forerunners. He knew the work of Ray who had sought to distinguish species from larger indefinite groups and who had seen fully the necessity of rules of nomenclature. But his was the fortunate psychological moment and he had his way. Others had used such ideas before him but never with such pertinacity or success with the public.
Animals and plants were denoted by two names. The first, generic, was such as to indicate a general group of creatures visibly related, such as all doglike forms, for example. The second adjectival name denoted a restricted specific group, a species, as the wolf among canids -- thus Canis lupus. He also recognized larger divisions such as classes and orders. As might be expected in any pioneering attempt, his botanical classification, based largely on the sexual parts, is not totally successful. Artificial systems of arrangement were in contrast to the "natural system" through comparative anatomy which had been sought by Ray.
It should be explained that an artificial system of classification is one in which a single organ -- as in the case of the sexual parts of plants -- is taken as a standard by which to classify a living group. The danger in such a system lies in the fact that some adaptive variation in the particular organ being used as the standard for classification may result in a particular plant's being wrongly classified. A natural system, on the other hand, takes account of all the organ systems and avoids arbitrary arrangements. Since the rise of evolution, taxonomical efforts in both zoology and botany have striven to determine affinity, that is, the relationship of any given group of plants or animals to a common ancestor. This, of course, was not clearly grasped by the first taxonomists.
Nevertheless, it must be said in justice to Linnaeus that as early as 1737 he had commented in a letter to Haller: "I have never spoken of that [his sexual system of botanical arrangement] as a natural method; on the contrary, in my Systema ... I have said, 'No natural botanical sys tem has as yet been constructed, though one or two may be more so than others; nor do I contend that this system is by any means natural.... Meanwhile, till that is discovered, artificial systems are indispensable: And in the preface to my Genera Plantarum, sect. 9: "I do not deny that a natural method is preferable, not only to my system, but to all that have been invented...." 
That pure naming and systems of classification got a little out of hand and took on a one-sided emphasis which persisted well into the nineteenth century need not be attributed solely to Linnaeus. He rose to fame in a period of great wonder and eagerness, to explore and catalogue the products of far lands. New words were pouring into European speech. The name was all and Linnaeus, with his gift for precise definition, with his exquisite taste for order, was providing the framework necessary to science before science could proceed to other things.
Further, if Linnaeus pursued the name, the name in its own way led to things no man could foresee. It was in his time, and owing greatly to his influence, that naturalists began to be apportioned posts on voyages of exploration. Cook's voyage on the Endeavor in 1768, to which Sir Joseph Banks contributed so heavily, is a case in point. It set the pattern which led eventually to Darwin's voyage on the Beagle. A letter from John Ellis, another of the English collectors, to Linnaeus in the year the Endeavor sailed speaks volumes on what Linnaeus had done for science, "No people ever went to sea better fitted for the purpose of Natural History," he writes, "nor more elegantly. They have got a fine library of Natural History; they have all sorts of machines for catching and preserving insects; all kinds of nets, trawls, drags, and hooks for coral fishing; they have even a curious contrivance of a telescope by which, put into the water, you can see the bottom to a great depth, where it is clear. They have many cases of bottles with ground stoppers, of several sizes, to preserve animals in spirits. They have the several sorts of salts to surround the seeds; and wax, both beeswax and that of Myrica; besides, there are many people whose sole business it is to attend them for this very purpose. They have two painters and draughtsmen, several volunteers who have a tolerable notion of Natural History; in short Solander  assured me this expedition would cost Mr. Banks ten thousand pounds. All this is owing to you and your writings."  (Italics mine. L.E.)
Linnaeus was not the uninspired drudge that men began to. regard him after the naming mania had passed. For him, as for all Christians of his era, there had been one act of creation. The modem species were as fixed as on the sixth day of God's labor. But he glimpsed, more than his fellows, the wonderful pattern of creation, the unities as well as the diversities of form that existed in the mind of God. Inspired by him men would die of fevers in Africa, or perish under the knives of Abyssinian bandits, .be pounded among the wreckage on coral reefs, or wander in the cloudland of unmapped mountains. It was for the name, his students thought, the beautiful order and arrangement of the living, the glimpse, as Linnaeus himself once expressed it, into the secret cabinet of God. But to the master himself in later years there must have come secretive glimpses of a wilder and more awe-inspiring wilderness than any through which the boldest of his students scrambled.
In erecting his classificatory system in such a manner as to cover the whole range of life he was unconsciously forecasting the possibility of its physical relationship. Curiously enough, though he had been quick to express the view that there were no new species, and this view in turn had been taken up and reiterated with great confidence in theological circles, there is clear evidence that he later came to doubt his own statements but by then was held fast in a doctrine at least partially of his own making.
V. The Fixity of Species
Scientists have long accused the church of holding back, by its preconceived beliefs, the progress of the evolutionary philosophy. The matter is actually more complicated than this:" Science, in the establishment of species as a fixed point from which to examine the organic world, gave to the concept a precision and fixity which it did not originally possess. Categories of plant and animal life, as we have previously observed, did not, in earlier centuries, possess the clarity that they began to take on at the hands of Ray and Linnaeus. Ail one astute but anonymous writer observed over fifty years ago: "Until the scientific idea of 'species' acquired form and distinctness there could be no dogma of 'special' creation in the modern sense. This form and distinctness it did not possess until the naturalists of the seventeenth century began to substitute exactness of definition for the previous vague characterizations of the objects of nature." 
As scientific delight and enthusiasm over the naming of new species grew with the expanding world of the voyagers, the conviction of the stability and permanence of the living world increased. Strict definition, so necessary to scientifically accurate analysis, led in the end to the total crystallization of the idea of order. It is true, as we have observed earlier, that the notion of the fixed Scale of Being and the Christian conception of time, as well as the Biblical account of Creation, all tended to discount the evolutionary hypothesis, but, ironically enough, it was Linnaeus with his proclamation that species were absolutely fixed since the beginning who intensified the theological trend. His vast prestige in both scientific and cultivated circles made it assured that his remarks would be heeded. Henceforth the church would take the fixity of species for granted. Science, in its desire for classification and order, had found itself satisfactorily allied with a Christian dogma whose refinements it had contributed to produce.
Yet no sooner had Linnaeus proclaimed his dogma than, while working in the botanical gardens of his patron Clifford at Hartecamp, he grew aware of the modem ·sportiveness" of nature. He saw varieties appear spontaneously, he saw "abnormal" plants derived from normal ones. Like Ray before him, but perhaps more clearly, he was forced to distinguish between the true species of the Creator and the varietal confusion and disorder of the moment, which might be artificially manipulated by the skill of gardeners. In this way he attempted to cling to his original thesis. He had assumed that all species come from original pairs created on a small island which, in the beginning, had constituted the only dry land, the original Eden of the world.
As one pursues this subject through his multitudinous writings and the ever mounting editions of the Systema Naturae one can trace a growing uncertainty and doubt. He sees the possibility of new species arising through crossbreeding. He confesses that he dare not decide ·whether all these species are the children of time, or whether the Creator from the very beginning of the world had restricted this course of development to a definite number of species."  He cautiously removes from later editions of the Systema the statement that no new species can arise. The fixity of species, the precise definition of the term, is no longer secure. "Nullae species novae" had been accepted by the world, but to the master taxonomist who had drawn the lines of relationship with geometric precision all was now wavering toward mutability and formlessness. Only the natural orders now seemed stable. What this actually might have meant to Linnaeus who had placed man along with monkeys in his order of the Primates, it is far too late to determine satisfactorily, but that he toyed with ideas of strange animal mixtures and permutations we know.
There is something awe-inspiringly symbolic about the stroke that destroyed his mental competence. It savors of the divine nemesis of which he had once written and long feared. He who in youth had beheld the beautiful radiating lines of life gleam for an instant like a spider web on a dew-hung morning glimpsed a truth which, as is true of so much human knowledge, was also an illusion. The rainbow bridge to the city of the gods had vanished, leaving an old, memoryless man. The passionate cataloguer of the Systema Naturae no longer knew his book. Finally, and most dreadful fate of all, there passed away from that proud, world-famous man the knowledge even of his own name. There remained in his garden only the dried husk of an old plant among new flowers reaching for the sun.
1. Religio Medici, 1635.
2 Primitivism and the Idea of Progress, Baltimore, 1934, p. 158.
3. Charles Darwin, The Origin of Species, New York: Philosophical Library, 1951, Chap. 2.
4. Sir Charles Lyell, Principles of Geology, Vol. 3, 3rd ed., London, 1834, pp. 84-85.
5. More Letters of Charles Darwin, ed. by Francis Darwin and A. C. Seward, London: John Murray, 1903, Vol. 1, p. 55.
6. Ray was not, of course, so beautiful a stylist as White.
7. Charles E. Raven, John Ray, Naturalist: His Life and Works, Cambridge University Press. 1943.
8. Sir James Edward Smith, A Selection of the Correspondence of Linnaeus and Other Naturalists from the Original Manuscripts. London, 1821, Vol. 2, p. 460.
9. Charles E. Raven, John Ray, Naturalist, p. 452 ff.
10. Robert Gunther, Further Correspondence of John Ray, London, 1928, p. 260.
11. Sir James Edward Smith, A Selection of the Correspondence of Linnaeus and Other Naturalists, London, 1821, Vol. 2, p. 458.
12. Ibid., p. 561.
13. Ibid., p. 399.
14. Ibid., Vol. 1, pp. 18-19.
15. Carl Linnaeus, London: Jonathan Cape, 1952, p. 159.
16. Cited from Hagberg, op. cit., p. 100.
17. Hagberg, op. cit., p. 10.
18. J. E. Smith, op. cit., Vol. 2, p. 232.
19. Solander was a student and protege of Linnaeus.
20. J. E. Smith. op. cit., Vol. I, p. 231.
21. "Lamarck, Darwin and Weismann," The Living Age, 1902, Vol. 235. p. 519.
22. Cited by Hagberg, op. cit., p. 202.