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On Natural History, as Knowledge, Discipline, and Power

The value of any pursuit depends upon the extent to which it fulfils one or all of three conditions. Either it enlarges our experience; or it increases our strength; or it diminishes the obstacles in the way of our acquiring experience and strength. Whatever neither teaches, nor strengthens, nor helps us, is either useless or mischievous. The scientific calling, like all others, must be submitted to these tests if we desire fairly to estimate its dignity and worth; and as the object of the present discourse is to set forth such an estimate of the science of Natural History, it will be necessary to consider–Firstly, its scope and range as mere knowledge; Secondly, the amount to which the process of acquiring Natural History knowledge strengthens and develops the powers of the gainer, its position, that is, as discipline; Thirdly, the extent to which it enables him, so to speak, to turn one part of the universe against another, in order to attain his own ends, and this is what is commonly called the power of science.

There can be little doubt as to which is the highest and noblest of these standards of value. Science, as power, indeed, showers daily blessings upon our practical life; and science, as knowledge, opens up continually new sources of intellectual delight. But neither knowing nor enjoying are the highest ends of life. Strength–capacity of action and of endurance–is the highest thing to be desired; and this is to be obtained only by careful discipline of all the faculties, by that training which the pursuit of science is, above all things, most competent to give.

First, let us regard Natural History as mere Knowledge.

The common conception of the aims of a naturalist of the present

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day does him great injustice, although it might perhaps fairly apply to one of a century and a half ago; when natural history, which began in the instinctive observation of the habits, and the study of the forms, of living beings, had hardly passed beyond the stage of more or less accurate anecdotes, and larger or smaller collections of curiosities.

The difference between the ancient naturalist and his modern successor is similar to that between the Chaldæan watcher of the stars and the modern astronomer; but the scientific progress of the race is epitomized in that of the individual, and may be best exemplified, perhaps, by tracing out the lines of inquiry into which any person of intelligence, who should faithfully attempt to solve the various problems presented by any living being, however simple and however humble, would necessarily be led. By the investigation of habits, the inquirer is insensibly led into Physiology, Psychology, Geographical and Geological distribution; by the investigation of the relations of forms, he is no less necessarily impelled into systematic Zoology and Botany, into Anatomy, Development, and Morphology, or Philosophical Anatomy. Now each of these great sciences is, if followed out into all its details, the sufficient occupation of a lifetime; but in their aggregate only, are they the equivalent of the science of natural history: and the title of naturalist, in the modern sense, is deserved only by one who has mastered the principles of all.

So much for the range of natural history. If we consider, not merely the number, but the nature of the problems which it presents, we shall find that they open up fields of thought unsurpassable in interest and grandeur. For instance, morphology demonstrates that the innumerable varieties of the forms of living beings are modelled upon a very small number of common plans or types. ("Haupt-Typen," of Von Bär, whose idea and term are merely paraphrased by "archetype," common plan, &c.) In the animal world we find only five of these common plans, that of the Protozoa, of the Cœlenterata, of the Mollusca, of the Annulosa, and of the Vertebrata. Not only are all animals existing in the present creation organized according to one of these five plans; but palæontology tends to show that in the myriads of past ages of which the earth's crust contains the records, no other plan of animal form made its appearance on our planet. A marvellous fact, and one which seems to present no small obstacle in the way of the notion of the possibly fortuitous development of animal life.

Not merely does the study of morphology lead us into the depths of past time, but it obliges us to gaze into that greater abyss which

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lies between the human mind and that mind of which the universe is but a thought and an expression. For man, looking from the heights of science into the surrounding universe, is as a traveller who has ascended the Brocken and sees, in the clouds, a vast image, dim and awful, and yet in its essential lineaments resembling himself. In the words of the only poet of our day who has fused true science into song, the philosopher, looking into Nature,

"Sees his shadow glory-crowned, He sees himself in all he sees."

Tennyson's "In Memoriam."

The mathematician discovers in the universe a "Divine Geometry;" the physicist and the chemist everywhere find that the operations of nature may be expressed in terms of the human intellect; and, in like manner, among living beings, the naturalist discovers that their "vital" processes are not performed by the gift of powers and faculties entirely peculiar and irrespective of those which are met with in the physical world; but that they are built up and their parts adapted together, in a manner which forcibly reminds us of the mode in which a human artificer builds up a complex piece of mechanism, by skilfully combining the simple powers and forces of the matter around him. The numberless facts which illustrate this truth are familiar to all, through the works of Paley and the natural theologians, whose arguments may be summed up thus–that the structure of living beings is, in the main, such as would result from the benevolent operation, under the conditions of the physical world, of an intelligence similar in kind, however superior in degree, to our own. Granting the validity of the premises, that from the similarity of effects we may argue to a similarity of cause, does natural history allow our conclusions to rest here? Is this utilitarian adaptation to a benevolent purpose the chief or even the leading feature of that great shadow, or, we should more rightly say, of that vast archetype of the human mind, which everywhere looms upon us through nature? The reply of natural history is clearly in the negative. She tells us that utilitarian adaptation to purpose is not the greatest principle worked out in nature, and that its value, even as an instrument of research, has been enormously overrated.

How is it then, that not only in popular works, but in the writings of men of deservedly high authority, we find the opposite dogma–that the principle of adaptation of means to ends is the great instrument of research in natural history–enunciated as an axiom? If we trace out the doctrine to its fountain head, we shall find that it was primarily put forth by Cuvier–the prince of modern naturalists. Is

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it to be supposed then that Cuvier did not himself understand the methods by which he arrived at his great results? that his master-mind misconceived its own processes? This conclusion appears to be not a little presumptuous; but if the following arguments be justly reasoned out, it is correct.

In the famous "Discours sur les Révolutions de la Surface du Globe," after speaking of the difficulties in the way of the restoration of vertebrate fossils, Cuvier goes on to say–

"Happily, comparative anatomy possesses a principle whose just development is sufficient to dissipate all difficulties; it is that of the correlation of forms in organized beings, by means of which every kind of organized being might, strictly speaking, be recognized by a fragment of any of its parts.

"Every organized being constitutes a whole, a single and complete system, whose parts mutually correspond, and concur, by their reciprocal reaction, to the same definite end. None of these parts can be changed without affecting the others; and consequently, each taken separately indicates and gives all the rest."

After this Cuvier gives his well-known examples of the correlation of the parts of a carnivore, too long for extract; and of which therefore his summation merely will be given:–

"In a word, the form of the tooth involves that of the condyle; that of the shoulder blade; that of the claws: just as the equation of a curve involves all its properties. And just as by taking each property separately and making it the base of a separate equation, we should obtain both the ordinary equation, and all other properties whatsoever which it possesses; so, in the same way, the claw, the scapula, the condyle, the femur, and all the other bones taken separately will give the tooth, or one another; and by commencing with any one, he who had a rational conception of the laws of the organic economy, could reconstruct the whole animal."

Thus far Cuvier: and thus far and no further, it seems that the compilers, and copyers, and popularizers, and id genus omne, proceed in the study of him. And so it is handed down from book to book, that all Cuvier's restorations of extinct animals were affected by means of the principle of the physiological correlation of organs.

Now let us examine this principle; taking in the first place, one of Cuvier's own arguments and analyzing it; and in the second place, bringing other considerations to bear.

Cuvier says–"It is readily intelligible that ungulate animals must all be herbivorous, since they possess no means of seizing a prey (1). We see very easily also, that the only use of their fore feet

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being to support their bodies, they have no need of so strongly formed a shoulder; whence follows the absence of clavicles (2) and acromion, and the narrowness of the scapula. No longer having any need to turn their fore-arm, the radius will be united with the ulna, or least articulated by a ginglymus and not arthrodially with the humerus (3). Their herbivorous diet will require teeth, with flat crowns, to bruise up the grain and herbage; these crowns must needs be unequal, and to this end enamel must alternate with bony matter (4); such a kind of crown requiring horizontal movements for trituration, the condyle of the jaw must not form so close a hinge as in the carnivora; it must be flattened; and this entails a correspondingly flattened temporal facet. The temporal fossa which will have to receive only a small temporal muscle will be shallow and narrow (5)."

The various propositions are here marked with numbers, to avoid repetition; and it is easy to show that not one is really based on a necessary physiological law:–

(1.) Why should not ungulate animals be carrion feeders? Or even, if living animals were their prey, surely a horse could run down and destroy other animals with at least as much ease as a wolf.

(2, 3.) But what purpose, save support, is subserved by the forelegs of the dog and wolf? how large are their clavicles? how much power have they of rotating the fore-arm?

(4, 5.) The sloth is purely herbivorous, but its teeth present no trace of any such alternation of substance.

Again, what difference exists in structure of tooth, in the shape of the condyle of the jaw, and in that of the temporal fossa, between the herbivorous and carnivorous bears? If bears were only known to exist in the fossil state, would any anatomist venture to conclude from the skull and teeth alone, that the white bear is naturally carnivorous, while the brown bear is naturally frugivorous? Assuredly not; and thus, in the case of Cuvier's own selection, we see that his arguments are absolutely devoid of conclusive force. Let us select another then: on the table is a piece of carboniferous shale, bearing the impression of an animal long since extinct. It is a mere impression of the external form, but this is amply sufficient to enable us to be morally certain that if we had a living specimen, we should find its jaws, if it had any, moving sideways–that its hard skeleton formed a sheath outside its muscles–that its nervous system was turned downwards when it walked–that the heart was placed on the opposite side of the body–that if it possessed special respiratory organs, they were gills, &c., &c.

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In fact, we have in the outward form abundant material for the restoration of the internal organs. But how do we conclude, from the peculiar many-ringed body, with jointed limbs, of this ancient marine animal, that it had all these other peculiarities; in short, that it was a crustacean? For any physiological necessity to the contrary, the creature might have had its mouth, nervous system, and internal organs arranged like those of a fish. We know that it was a crustacean and not a fish, simply because the observation of a vast number of instances assures us that an external structure such as this creature possesses, is invariably accompanied by the internal peculiarities enumerated. Our method then is not the method of adaptation, of necessary physiological correlations; for of such necessities, in the case in question, we know nothing: but it is the method of agreement; that method by which, having observed facts invariably occur together, we conclude they invariably have done so, and invariably will do so; a method used as much in the common affairs of life as in philosophy.

Multitudes of like instances could be adduced from the animal world; and if we turn to the botanist, and inquire how he restores fossil plants from their fragments, he will say at once that he knows nothing of physiological necessities and correlations. Give him a fragment of wood, and he will unhesitatingly tell you what kind of a plant it belonged to, but it will be fruitless to ask him what physiological necessity combines, e.g. peculiarly dotted vessels, with fruit in the shape of a cone and naked ovules, for he knows of none. Nevertheless, his restorations stand on the same logical basis as those of the zoologist.

Therefore, whatever Cuvier himself may say, or others may repeat, it seems quite clear that the principle of his restorations was not that of the physiological correlation or coadaptation of organs. And if it were necessary to appeal to any authority, save facts and reason, our first witness should be Cuvier himself, who, in a very remarkable passage, two or three pages further on (Discours, pp. 184-185,1) implicitly surrenders his own principle.

Thus then natural history plainly teaches us that the utilitarian principle, valuable enough in physiology, helps us no further, and is utterly insufficient as an instrument of morphological research.

But does she then tell us that in this, her grander sphere, the human mind discovers no reflex, and that among those forms of being which most approach himself alone, man can discover no indication

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of that vast harmony with his own nature which seemed so obvious elsewhere? Surely not. On the contrary, it may be regarded as one of the noblest characteristics of natural history knowledge, that its highest flights point, not to a discrepancy between the infinite and the finite mind, but to a higher and closer union than can be imagined by those whose studies are confined to the physical world. For where the principle of adaptation, of mere mechanical utilitarian contrivance fails us, it is replaced by another which appeals to the æsthetic sense as much as the mere intellect.

Regard a case of birds, or of butterflies, or examine the shell of an echinus, or a group of foraminifera, sifted out of the first handful of sea sand. Is it to be supposed for a moment that the beauty of outline and colour of the first, the geometrical regularity of the second, or the extreme variety and elegance of the third, are any good to the animals? that they perform any of the actions of their lives more easily and better for being bright and graceful, rather than if they were dull and plain? So, to go deeper, is it conceivable that the harmonious variation of a common plan which we find everywhere in nature serves any utilitarian purpose? that the innumerable varieties of antelopes, of frogs, of clupeoid fishes, of beetles, and bivalve mollusks, of polyzoa, of actinozoa, and hydrozoa, are adaptations to as many different kinds of life, and consequently varying physiological necessities? Such a supposition with regard to the three last, at any rate, would be absurd; the polyzoa, for instance, presenting a remarkable uniformity in mode of life and internal organization, while nothing can be more striking than the wonderful variety of their external shape and of the sculpture of their cells. If we turn to the vegetable world, we find it one vast illustration of the same truth. Who has ever dreamed of finding an utilitarian purpose in the forms and colours of flowers, in the sculpture of pollen-grains, in the varied figures of the frond of ferns? What "purpose" is served by the strange numerical relations of the parts of plants, the threes and fives of monocotyledons and dicotyledons?

Thus in travelling from one end to the other of the scale of life, we are taught one lesson, that living nature is not a mechanism but a poem; not a mere rough engine-house for the due keeping of pleasure and pain machines, but a palace whose foundations, indeed, are laid on the strictest and safest mechanical principles, but whose superstructure is a manifestation of the highest and noblest art.

Such is the plain teaching of Nature. But if we have a right to conclude from the marks of benevolent design to an infinite

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Intellect and Benevolence, in some sort similar to our own, then from the existence of a beauty (nay, even of a humour), and of a predominant harmonious variety in unity in nature, which, if the work of man, would be regarded as the highest art, we are similarly bound to conclude that the æsthetic faculties of the human soul have also been foreshadowed in the Infinite Mind.

Such is a brief indication of the regions of thought into which natural history leads us, and we may surely conclude that as Knowledge it stands second in scope and breadth to no science.

As Discipline, impartial consideration will show that it takes no lower rank; whether we regard it as a gymnastic for the intellectual, the moral, or the æsthetic faculty.

For the successful carrying on of the business of life, no less than for the pursuit of science, it is essential that the mind should easily and accurately perform the four great intellectual processes of observation, experiment, induction, and deduction. No training can be so well adapted to develop the first of these faculties as that of the naturalist, the very foundation of whose studies lies in exact observation of characters and nice discrimination of resemblances and differences. In fact, the skilled naturalist is the only man who combines the moral and intellectual advantages of civilization with that acuteness and minute accuracy of perception which distinguish the savage hunter; and if man's senses are to keep pace with his intellect as the world grows older, natural history observation must be made a branch of ordinary education.

Again, what science can present more perfect examples of the application of the methods of experiment than physiology? All that we know of the physiology of the nervous system rests on experiment; and if we turn to other functions, the investigations of Bernard might be cited as striking specimens of experimental research.

To say that natural history as a science is equivalent to the assertion that it exercises the inductive and deductive faculties; but it is often forgotten that the so-called "natural classification" of living beings is, in reality, not mere classification, but the result of a great series of inductive investigations. In a "natural classification" the definitions of the classes are, in fact, the laws of living form, obtained, like all other laws, by a process of induction from observed facts.

For examples of the exercise of deduction, of the arguing from the laws of living form obtained by induction, to their legitimate consequences, the whole science of palæontology may be cited.

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As has already been already shown, the whole process of palæontological restoration depends–First, on the validity of a law of the invariable coincidence of certain organic peculiarities established by induction; Secondly, on the accuracy of the logical process of deduction from this law. Professor Owen's determination of the nature of the famous Stonesfield mammal is a striking illustration of this. A small jaw of a peculiar shape was found, containing a great number of teeth, some of which were imbedded by double fangs in the jaw.

Now these laws have been inductively established–

(a) That only mammals have teeth imbedded in a double socket.

(b) That only marsupials have teeth in so great a number, imbedded in so peculiarly formed a jaw.

By deduction from these laws to the case in question, the legitimate conclusion was arrived at, that the jaw belonged to a marsupial mammal.

The naturalist then, who faithfully follows his calling leaves no side of his intellect untrained; but, after all, intellect, however gigantic, confers but half the qualifications required by one who desires to follow science with success, and he who gains only knowledge from her, gains but little. The moral faculties of courage, patience, and self-denial, are of as much value in science as in life; the origin of an erroneous doctrine lies as often in the heart as in the head; and the basis of the character of a great philosopher will commonly be found, on close analysis, to be earnest truthfulness–and no imaginary gift of genius. It is character and not talent which is the essential element of success in science. But as the muscle of the smith grows stronger by reason of its constant use in hammering, so it seems impossible to doubt that the training of the moral faculty, necessarily undergone by the philosopher, must react upon the man. There are, indeed, lamentable examples of men who seem to have one moral faculty for science, and another for their daily affairs: but such instances are hardly found in the highest ranks of philosophy; and when they occur, the daily poison may be traced spreading higher and higher, and sooner or later falling like a Nemesis upon the scientific faculty.

Let those who doubt the efficacy of science as moral discipline make the experiment of trying to come to a comprehension of the meanest worm or weed, of its structure, its habits, its relation to the great scheme of nature. It will be a most exceptional case, if the mere endeavour to give a correct outline of its form, or to describe its appearance with accuracy, do not call into exercise far more patience,

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perseverance, and self-denial than they have easily at command; and if they do not rise up from the attempt, in utter astonishment at the habitual laxity and inaccuracy of their mental processes, and in some dismay at the pertinacious manner in which their subjective conceptions and hasty preconceived notions interfere with their forming a truthful conception of objective fact. There is not one person in fifty whose habits of mind are sufficiently accurate to enable him to give a truthful description of the exterior of a rose.

Finally, the power of natural history was illustrated by examples of recent applications of that science in opening up sources of industrial wealth.

1 Ossemens Fossiles, 4me édition, T. 1.