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22. There is therefore nothing, in what we know of the Cosmical conditions of our globe, to contradict the Terrestrial evidence for its vast antiquity, as the seat of organic life. If for the sake of giving definiteness to our notions, we were to assume that the numbers which express the antiquity of these four Periods;—the Present organic condition of the earth; the Tertiary Period of geologists, which preceded that; the Secondary Period, which was anterior to that; and the Primary Period which preceded the Secondary; were on the same scale as the numbers which express these four magnitudes:—the magnitude of the Earth; that of the Solar System compared with the Earth; the distance of the nearest Fixed Stars compared with the solar system; and the distance of the most remote Nebulæ compared with the nearest fixed stars; there is, in the evidence which geological science offers, nothing to contradict such an assumption.
23. And as the infinite extent which we necessarily ascribe to space, allows us to find room, without any mental difficulty, for the vast distances which astronomy reveals, and even leaves us rather embarrassed with the infinite extent which lies beyond our farthest explorations; so the infinite duration which we, in like manner, necessarily ascribe to past time, makes it easy for us, so far as our powers of intellect are concerned, to go millions of millions of years backwards, in order to trace the beginning of the earth's existence,—the first step of terrestrial creation. It is as easy for the mind of man to reason respecting a system which is billions or trillions of miles in extent, and has endured through the like number of years, or centuries, as it is to reason about a system (the earth, for instance,) which is forty million feet in extent, and has endured for a hundred thousand million of seconds, that is, a few thousand years.
24. This statement is amply sufficient for the argument which we have to found upon it; but before I proceed to do that, I will give another view which has recently been adopted by some geologists, of the mode in which the successive periods of creation, which geological research discloses to us, have passed into one another. According to this new view, we find no sufficient reason to believe that the history of the earth, as read by us in the organic and mechanical phenomena of its superficial parts, has consisted of such an alternation of periods of violence and of repose, as we have just attempted to describe. According to these theorists, strata have succeeded strata, one group of animals and plants has followed another, through a season of uniform change; with no greater paroxysm or catastrophe, it may be, than has occurred during the time that man has been an observer of the earth. It may be asked, how is this consistent with the phenomena which we have described;—with the vast masses of ruin, which mark the end of one period and the beginning of another, as is the case in passing from the coal measures of England to the superincumbent beds;—with the highly-inclined strata of the central masses, and the level beds of the upper formations which have been described as marking the mountain ranges of Europe? To these questions, a reply is furnished, we are told, by a more extensive and careful examination of the strata. It may be, that in certain localities, in certain districts, the transition, from the mountain limestone and the coal, to the superjacent sandstones and oolites, is abrupt and seemingly violent; marked by unconformable positions of the upper upon the lower strata, by beds of conglomerate, by the absence of organic remains in certain of these beds. But if we follow these very strata into other parts of the world, or even into other parts of this island, we find that this abruptness and incongruity between the lower and the higher strata disappears. Between the mountain-limestone and the red sandstone which lies over it, certain new beds are found, which fill up the incoherent interval; which offer the same evidence as the strata below and above them, of having been produced tranquilly; and which do not violently differ in position from either group. The appearance of incoherence in the series arose from the occurrence, in the region first examined, of a gap, which is here filled up,—a blank which is here supplied. Hence it is inferred, that whatever of violence and extreme disturbance is indicated by the dislocations and ruins there observed, was local and partial only; and that, at the very time when these fragmentary beds, void of organized beings, were forming in one place, there were, at the same time, going on, in another part of the earth's surface, not far removed, the processes of the life, death and imbedding of species, as tranquilly as at any other period. And the same assertion is made with regard to the more general fact, before described, of the stratigraphical constitution of mountain chains. It is asserted that the unconformable relation of the strata which compose the different parts of those chains, is a local occurrence only; and that the same strata, if followed into other regions, are found conformable to each other; or are reduced to a virtually continuous scheme, by the interpolation of other strata, which make a transition, in which no evidence of exceptional violence appears.
25. We shall not attempt (it is not at all necessary for us to do so) to decide between the doctrines of the two geological schools which thus stand in this opposition to each other. But it will be useful to our argument to state somewhat further the opinions of this latter school on one main point. We must explain the view which these geologists take of the mode of succession of one group of organized beings to another; by which, as we have said, the different successive strata are characterized. Such a phenomenon, it would at first seem, cannot be brought within the ordinary rules of the existing state of things. The species of plants and animals which inhabit the earth, do not change from age to age; they are the same in modern times, as they were in the most remote antiquity, of which we have any record. The dogs and horses, sheep and cattle, lions and wolves, eagles and swallows, corn and vines, oaks and cedars, which occupy the earth now, are not, we have the strongest reasons to believe, essentially different now from what they were in the earliest ages. At least, if one or two species have disappeared, no new species have come into existence. We cannot conceive a greater violation of the known laws of nature, than that such an event as the appearance of a new species should have occurred. Even those who hold the uniformity of the mechanical changes of the earth, and of the rate of change, from age to age, and from one geological period to another; must still, it would seem, allow that the zoological and phytological changes of which geology gives her testimony, are complete exceptions to what is now taking place. The formation of strata at the bottom of the ocean from the ruin of existing continents, may be going on at present. Even the elevation of the bed of the ocean in certain places, as a process imperceptibly slow, may be in action at this moment, as these theorists hold that it is. But still, even when the beds thus formed are elevated into mountain chains, if that should happen, in the course of myriads of years, (according to the supposition it cannot be effected in a less period,) the strata of such mountain chains will still contain only the species of such creatures as now inhabit the waters; and we shall have, even then, no succession of organic epochs, such as geology discovers in the existing mountains of the earth.
26. The answer which is made to this objection appears to me to involve a license of assumption on the part of the uniformitarian geologist, (as such theorists have been termed,) which goes quite beyond the bounds of natural philosophy: but I wish to state it; partly, in order to show that the most ingenious men, stimulated by the exigencies of a theory, which requires some hypothesis concerning the succession of species, to make it coherent and complete, have still found it impossible to bring the creation of species of plants and animals within the domain of natural science; and partly, to show how easily and readily geological theorists are led to assume periods of time, even of a higher order than those which I have ventured to suggest.
27. It must, however, be first stated, as a fact on which the assumption is founded which I have to notice, that the organic groups by which these successive strata are characterized, are not so distinct and separate, as it was convenient, for the sake of explanation, to describe them in the first instance. Although each body of strata is marked by predominant groups of genera and species, yet it is not true, that all the species of each formation disappear, when we proceed to the next. Some species and genera endure through several successive groups of strata; while others disappear, and new forms come into view, as we ascend. And thus, the change from one set of organic forms to another, as we advance in time, is made, not altogether by abrupt transitions, but in part continuously. The uniformitarian, in the case of organic, as in the case of mechanical change, obliterates or weakens the evidence of sudden and catastrophic leaps, by interposing intermediate steps, which involve, partly the phenomena of the preceding, and partly those of the subsequent condition. As he allows no universal transition from one deposit to a succeeding discrepant and unconformable deposit, so he allows no abrupt and complete transition from one collection of organic beings,—one creation, as we may call it,—to another. If creation must needs be an act out of the region of natural science, he will have it to be at least an act not exercised at distant intervals, and on peculiar occasions; but constantly going on, and producing its effects, as much at one time in the geological history of the world, as at another.
28. And this he holds, not only with regard to the geological periods which have preceded the existing condition of the earth, but also with regard to the transition from those previous periods to that in which we live. The present population of the earth is not one in which all previous forms are extinct. The past population of the earth was not one in which there are found no creatures still living. On the contrary, he finds that there exists a vast mass of strata, superior to the secondary strata, which are characterized by extinct forms, and are yet inferior to those deposits which are now going on by the agency of obvious causes. These masses of strata contain a population of creatures, partly extinct species, and partly such species as are still living on our land and in our waters. The proportion in which the old and the new species occur in such strata, is various; and the strata are so numerous, so rich in organic remains, so different from each other, and have been so well explored, that they have been classified and named according to the proportion of new and of old species which they contain. Those which contain the largest proportion of species still living, have been termed Pliocene, as containing a greater number of new or recent species. Below these, are strata which are termed Miocene, implying a smaller number of new species. Below these again, are others which have been termed Eocene, as containing few new species indeed, but yet enough to mark the dawn, the Eos, of the existing state of the organic world. These strata are, in many places, of very considerable thickness; and their number, their succession, and the great amount of extinct species which they contain, shows, in a manner which cannot be questioned, (if the evidence of geology is accepted at all,) in what a gradual manner, a portion at least, of the existing forms of organic life have taken the place of a different population previously existing on the surface of the globe.
29. And thus the uniformitarian is led to consider the facts which geology brings to light, as indicating a slow and almost imperceptible, but, upon the whole, constant series of changes, not only in the position of the earth's materials, but in its animal and vegetable population. Land becomes sea and sea becomes land; the beds of oceans are elevated into mountain regions, carrying with them the remains of their inhabitants; sheets of lava pour from volcanic vents and overwhelm the seats of life; and these, again, become fields of vegetation; or, it may be, descend to the depths of the sea, and are overgrown with groves of coral; lakes are filled with sediment, imbedding the remains of land animals, and form the museums of future zoologists; the deltas of mighty rivers become the centres of continents, and are excavated as coal-fields by men in remote ages. And yet all this time, so slow is the change, that man is unaware such changes are going on. He knows that the mountains of Scandinavia are rising out of the Baltic at the rate of a few feet in a century; he knows that the fertile slope of Etna has been growing for thousands of years by the addition of lava streams and parasitic volcanos; he knows that the delta of the Mississippi accumulates hundreds of miles of vegetable matter every generation; he knows that the shores of Europe are yielding to the sea; but all these appear to him minute items, not worth summing; infinitesimal quantities, which he cannot integrate. And so, in truth, they are, for him. His ephemeral existence does not allow him to form a just conception, in any ordinary state of mind, of the effects of this constant agency of change, working through countless thousands of years. But Time, inexhausted and unremitting, sums the series, integrates the formula of change; and thus passes, with sure though noiseless progress, from one geological epoch to another.
30. And in the meanwhile, to complete the view thus taken by the uniformitarian of the geological history of the earth, by some constant but inscrutable law, creative agency is perpetually at work, to introduce, into this progressive system of things, new species of vegetable and animal life. Organic forms, ever and ever new ones, are brought into being, and left, visible footsteps, as it were, of the progress which Time has made;—marks placed between the rocky leaves of the book of creation; by which man, when his time comes, may turn back and read the past history of his habitation. But the point for us to remark is, the immeasurable, the inconceivable length of time, if any length of time could be inconceivable, which is required of our thoughts, by this new assumption of the constant production of new species, as a law of creation. We might feel ourselves well nigh overwhelmed, when, by looking at processes which we see producing only a few feet of height or breadth or depth during the life of man, we are called upon to imagine the construction of Alps and Andes,—when we have to imagine a world made a few inches in a century. But there, at least, we had something to start from: the element of change was small, but there was an element of change: we had to expand, but we had not to originate. But in conceiving that all the myriads of successive species, which we find in the earth's strata, have come into being by a law which is now operating, we have nothing to start from. We have seen, and know of, no such change; all sober and skilful naturalists reject it, as a fact not belonging to our time. We have here to build a theory without materials;—to sum a series of which every term, so far as we know, is nothing;—to introduce into our scientific reasonings an assumption contrary to all scientific knowledge.
31. This appears to me to be the real character of the assumption of the constant creation of new species. But, as I have said, it is not my business here, to pronounce upon the value or truth of this assumption. The only use which I wish to make of it is this:—If any persons, who have adopted the geological view which I have just been explaining, should feel any interest in the speculations here offered to their notice, they must needs be (as I have no doubt they will be) even more willing than other geologists, to grant to our argument a scale of time for geological succession, corresponding in magnitude to the scale of distances which astronomy teaches us, as those which measure the relation of the universe to the earth.
This being supposed to be granted, I am prepared to proceed with my argument.
CHAPTER VI
THE ARGUMENT FROM GEOLOGY
1. I have endeavored to explain that, according to the discoveries of geologists, the masses of which the surface of the earth is composed, exhibit indisputable evidence that, at different successive periods, the land and the waters which occupy it, have been inhabited by successive races of plants and animals; which, when taken in large groups, according to the ascending or descending order of the strata, consist of species different from those above and below them. Many of these groups of species are of forms so different from any living things which now exist, as to give to the life of those ancient periods an aspect strangely diverse from that which life now displays, and to transfer us, in thought, to a creation remote in its predominant forms from that among which we live. I have shown also, that the life and successive generations of these groups of species, and the events by which the rocks which contain these remains have been brought into their present situation and condition, must have occupied immense intervals of time;—intervals so large that they deserve to be compared, in their numerical expression, with the intervals of space which separate the planets and stars from each other. It has been seen, also, that the best geologists and natural historians have not been able to devise any hypothesis to account for the successive introduction of these new species into the earth's population; except the exercise of a series of acts of creation, by which they have been brought into being; either in groups at once, or in a perpetual succession of one or a few species, which the course of long intervals of time might accumulate into groups of species. It is true, that some speculators have held that by the agency of natural causes, such as operate upon organic forms, one species might be transmuted into another; external conditions of climate, food, and the like, being supposed to conspire with internal impulses and tendencies, so as to produce this effect. This supposition is, however, on a more exact examination of the laws of animal life, found to be destitute of proof; and the doctrine of the successive creation of species remains firmly established among geologists. That the extinction of species, and of groups of species, may be accounted for by natural causes, is a proposition much more plausible, and to a certain extent, probable; for we have good reason to believe that, even within the time of human history, some few species have ceased to exist upon the earth. But whether the extinction of such vast groups of species as the ancient strata present to our notice, can be accounted for in this way, at least without assuming the occurrence of great catastrophes, which must for a time, have destroyed all forms of life in the district in which they occurred, appears to be more doubtful. The decision of these questions, however, is not essential to our purpose. What is important is, that immense numbers of tribes of animals have tenanted the earth for countless ages, before the present state of things began to be.
2. The present state of things is that to which the existence and the history of Man belong; and the remark which I now have to make is, that the existence and the history of Man are facts of an entirely different order from any which existed in any of the previous states of the earth; and that this history has occupied a series of years which, compared with geological periods, may be regarded as very brief and limited.
3. The remains of man are nowhere found in the strata which contain the records of former states of the earth. Skeletons of vast varieties of creatures have been disinterred from their rocky tombs; but these cemeteries of nature supply no portion of a human skeleton. In earlier periods of natural science, when comparative anatomy was as yet very imperfectly understood, no doubt, many fossil bones were supposed to be human bones. The remains of giants and of antediluvians were frequent in museums. But a further knowledge of anatomy has made it appear that such bones all belong to animals, of one kind or another; often, to animals utterly different, in their form and skeleton, from man. Also some bones, really human, have been found petrified in situations in which petrification has gone on in recent times, and is still going on. Human skeletons, imbedded in rocks by this process, have been found in the island of Guadaloupe, and elsewhere. But this phenomenon is easily distinguishable from the petrified bones of other animals, which are found in rocks belonging to really geological periods; and does not at all obliterate the distinction between the geological and the historical periods.
4. Indeed not bones only, but objects of art, produced by human workmanship, are found fossilized and petrified by the like processes; and these, of course, belong to the historical period. Human bones, and human works, are found in such deposits as morasses, sand-banks, lava-streams, mounds of volcanic ashes; and many of them may be of unknown, and, compared with the duration of a few generations, of very great antiquity; but such deposits are distinguishable, generally without difficulty, from the strata in which the geologist reads the records of former creations. It has been truly said, that the geologist is an Antiquary; for, like the antiquary, he traces a past condition of things in the remains and effects of it which still subsist; but it has also been truly said, at the same time, that he is an antiquary of a new Order; for the remains which he studies are those which illustrate the history of the earth, not of man. The geologist's antiquity is not that of ornaments and arms, utensils and habiliments, walls and mounds; but of species and of genera, of seas and of mountains. It is true, that the geologist may have to study the works of man, in order to trace the effects of causes which produce the results which he investigates; as when he examines the pholad-pierced pillars of Pateoli, to prove the rise and the fall of the ground on which they stand; or notes the anchoring-rings in the wall of some Roman edifice, once a maritime fort, but now a ruin remote from the sea; or when he remarks the streets in the towns of Scania, which are now below the level of the Baltic,4 and therefore show that the land has sunk since these pavements were laid. But in studying such objects, the geologist considers the hand of man as only one among many agencies. Man is to him only one of the natural causes of change.
5. And if, with the illustrious author to whom we have just referred,5 we liken the fossil remains, by which the geologist determines the age of his strata, to the Medals and Coins in which the antiquary finds the record of reigns and dynasties; we must still recollect that a Coin really discloses a vast body of characteristics of man, to which there is nothing approaching in the previous condition of the world. For how much does a Coin or Medal indicate? Property; exchange; government; a standard of value; the arts of mining, assaying, coining, drawing, and sculpture; language, writing, and reckoning; historical recollections, and the wish to be remembered by future ages. All this is involved in that small human work, a Coin. If the fossil remains of animals may (as has been said) be termed Medals struck by Nature to record the epochs of her history; Medals must be said to be, not merely, like fossil remains, records of material things; they are the records of thought, purpose, society, long continued, long improved, supplied with multiplied aids and helps; they are the permanent results, in a minute compass, of a vast progress, extending through all the ramifications of human life.
6. Not a coin merely, but any, the rudest work of human art, carries us far beyond the domain of mere animal life. There is no transition from man to animals. No doubt, there are races of men very degraded, barbarous, and brutish. No doubt there are kinds of animals which are very intelligent and sagacious; and some which are exceedingly disposed to and adapted to companionship with man. But by elevating the intelligence of the brute, we do not make it become the intelligence of the man. By making man barbarous, we do not make him cease to be a man. Animals have their especial capacities, which may be carried very far, and may approach near to human sagacity, or may even go beyond it; but the capacity of man is of a different kind. It is a capacity, not for becoming sagacious, but for becoming rational; or rather it is a capacity which he has in virtue of being rational. It is a capacity of progress. In animals, however sagacious, however well trained, the progress in skill and knowledge is limited, and very narrowly limited. The creature soon reaches a boundary, beyond which it cannot pass; and even if the acquired habits be transmitted by descent to another generation, (which happens in the case of dogs and several other animals,) still the race soon comes to a stand in its accomplishments. But in man, the possible progress from generation to generation, in intelligence and knowledge, and we may also say, in power, is indefinite; or if this be doubted, it is at least so vast, that compared with animals, his capacity is infinite. And this capacity extends to all races of men its characterizing efficacy: for we have good reason to believe that there is no race of human beings who may not, by a due course of culture, continued through generations, be brought into a community of intelligence and power with the most intelligent and the most powerful races. This seems to be well established, for instance, with regard to the African negroes; so long regarded by most, by some probably regarded still, as a race inferior to Europeans. It has been found that they are abundantly capable of taking a share in the arts, literature, morality and religion of European peoples. And we cannot doubt that, in the same manner, the native Australians, or the Bushmen of the Cape of Good Hope, have human faculties and human capacities; however difficult it might be to unfold these, in one or two generations, into a form of intelligence and civilization in any considerable degree resembling our own.
7. It is not requisite for us, and it might lead to unnecessary difficulties, to fix upon any one attribute of man, as peculiarly characteristic, and distinguishing him from brutes. Yet it would not be too much to say that man is, in truth, universally and specifically characterized by the possession of Language. It will not be questioned that language, in its highest forms, is a wonderful vehicle and a striking evidence of the intelligence of man. His bodily organs can, by a few scarcely perceptible motions, shape the air into sounds which express the kinds, properties, actions and relations of things, under thousands of aspects, in forms infinitely more general and recondite than those in which they present themselves to his senses;—and he can, by means of these forms, aided by the use of his senses, explore the boundless regions of space, the far recesses of past time, the order of nature, the working of the Author of nature. This man does, by the exercise of his Reason, and by the use of Language, a necessary implement of his Reason for such purposes.
8. That language, in such a stage, is a special character of man, will not be doubted. But it may be thought, there is little resemblance between Language in this exalted degree of perfection, and the seemingly senseless gibberish of the most barbarous tribes. Such an opinion, however, might easily be carried too far. All human language has in it the elements of indefinite intellectual activity, and the germs of indefinite development. Even the rudest kind of speech, used by savages, denotes objects by their kinds, their attributes, their relations, with a degree of generality derived from the intellect, not from the senses. The generality may be very limited; the relations which the human intellect is capable of apprehending may be imperfectly conveyed. But to denote kinds and attributes and actions and relations at all, is a beginning of generalization and abstraction;—or rather, is far more than a beginning. It is the work of a faculty which can generalize and abstract; and these mental processes once begun, the field of progress which is open to them is indefinite. Undoubtedly it may happen that weak and barbarous tribes are, for many generations, so hard pressed by circumstances, and their faculties so entirely absorbed in providing for the bare wants of the poorest life, that their thoughts may never travel to anything beyond these, and their language may not be extended so as to be applicable to any other purposes. But this is not the standard condition of mankind. It is not, by such cases, that man, or that human nature, is to be judged. The normal condition of man is one of an advance beyond the mere means of subsistence, to the arts of life, and the exercise of thought in a general form. To some extent, such an advance has taken place in almost every region of the earth and in every age.
9. Perhaps we may often have a tendency to think more meanly than they deserve, of so-called barbarous tribes, and of those whose intellectual habits differ much from our own. We may be prone to regard ourselves as standing at the summit of civilization; and all other nations and ages, as not only occupying inferior positions, but positions on a slope which descends till it sinks into the nature of brutes. And yet how little does an examination of the history of mankind justify this view! The different stages of civilization, and of intellectual culture, which have prevailed among them, have had no appearance of belonging to one single series, in which the cases differed only as higher or lower. On the contrary, there have been many very different kinds of civilization, accompanied by different forms of art and of thought; showing how universally the human mind tends to such habits, and how rich it is in the modes of manifesting its innate powers. How different have been the forms of civilization among the Chinese, the Indians, the Egyptians, the Babylonians, the Mexicans, the Peruvians! Yet in all, how much was displayed of sagacity and skill, of perseverance and progress, of mental activity and grasp, of thoughtfulness and power. Are we, in thinking of these manifestations of human capacity, to think of them as only a stage between us and brutes? or are we to think so, even of the stoical Red Indians of North America, or the energetic New Zealanders, and Caffres? And if not, why of the African Negroes, or the Australians, or the Bushmen? We may call their Language a jargon. Very probable it would, in its present form, be unable to express a great deal of what we are in the habit of putting into language. But can we refuse to believe that, with regard to matters with which they are familiar, and on occasions where they are interested, they would be to each other intelligible and clear? And if we suppose cases in which their affections and emotions are strongly excited, (and affections and emotions at least we cannot deny them,) can we not believe that they would be eloquent and impressive? Do we not know, in fact, that almost all nations which we call savage, are, on such occasions, eloquent in their own language? And since this is so, must not their language, after all, be a wonderful instrument as well as ours? Since it can convey one man's thoughts and emotions to many, clothed in the form which they assume in his mind; giving to things, it may be, an aspect quite different from that which they would have if presented to their own senses; guiding their conviction, warming their hearts, impelling their purposes;—can language, even in such cases, be otherwise than a wonderful produce of man's internal, of his mental, that is, of his peculiarly human faculties? And is not language, therefore, even in what we regard as its lowest forms, an endowment which completely separates man from animals which have no such faculty?—which cannot regard, or which cannot convey, the impressions of the individual in any such general and abstract form? Probably we should find, as those who have studied the language of savages always have found, that every such language contains a number of curious and subtle practices,—contrivances, we cannot help calling them,—for marking the relations, bearings and connections of words; contrivances quite different from those of the languages which we think of as more perfect; but yet, in the mouths of those who use such speech, answering their purpose with great precision. But without going into such details, the use of any articulate language is, as the oldest Greeks spoke of it, a special and complete distinction of man as man.