Chapter I

EMPIRES AND KINGDOMS OF NATURE.—THE HUMAN KINGDOM.—ANTHROPOLOGICAL METHOD.

I. The naturalist who meets with an object for the first time, instinctively asks the question:—What is this object? This question leads to another:—With what other objects shall I class it? To what group, and, in the first place, to what kingdom does it belong? Is it a mineral, a plant, or an animal?

The answer is not always easy. We know that, in what may be called the basis of each kingdom, there are ambiguous forms, whose nature has long been, and still is, the subject of contention among naturalists. We know that polyps were long regarded as plants, and that nullipores, at first taken for polyps, are now divided between the vegetable and mineral kingdoms; and, finally, we know that even now, botanists and zoologists dispute over certain diatoms and transfer them from one kingdom to the other.

Similarly the question has been asked:—What is man? and it has been answered from several points of view. To the naturalist it has but one meaning, and signifies, in which kingdom must man be placed? or better: is man an animal?

In spite of all the differences which a comparison of man with the mammalia presents, should he be classed with them? This question is similar to that which Peysonnel is said to have asked himself, when, struck by the special phenomena presented by the coral, he asked himself whether the object before him was a vegetable.

It is evident that, in order to solve the first problem which arises from a study of the natural history of man, we must have a clear idea what are these great groups of beings, which are called kingdoms; we must give an account of the characters which distinguish and separate them from each other, and then of their true scientific meaning. It will be sufficient for the purpose to explain the well-known laws of Linnæus, supplementing the theory of the immortal Swede by some ideas borrowed from Pallas and de Candolle, and by one of the fundamental conceptions which Adamson and A. L. de Jussieu have almost equally contributed to introduce into science.

II. It is impossible for anyone, whether learned or otherwise, not to recognise at once the difference between two kinds of objects very distinct from each other: inanimate bodies and organised beings. These are the two groups into which Pallas has divided kingdoms under the name of empires. Their distinction is generally easy, and I shall confine myself to recalling some of the most essential differences.

Inanimate bodies, when placed under favourable circumstances, last for an indefinite time, neither taking nor giving anything to the surrounding world; organised beings, under whatever conditions they are placed, only last for a fixed period of time, and, during this existence, undergo every moment losses of substance which they repair by means of materials taken from without. Inanimate bodies, even when they assume the fixed and definite form of crystals, are formed independently of all other bodies resembling them; they have from their commencement fixed forms, and increase simply by superposition of new layers. Every organised being is connected either directly or indirectly with a similar being, in the interior of which it first appeared in the form of a germ, then grew and acquired its definite form by intussusception.

In other words, filiation, nutrition, birth and death, are so many characteristics of the organised being, of which no trace is found in inanimate bodies. I agree with Pallas in making inanimate bodies compose the Inorganic Empire, and organised beings the Organic Empire.

I must here make an observation, the importance of which will be easily understood.

The existence of the two groups which have been recognised by the good sense of the general public as well as by the science of Pallas, is a fact absolutely independent of all hypothesis. Whatever explanation we may propose to account for the differential phenomena which distinguish them, these phenomena will not the less exist; the inanimate body will never be an organised being.

To attempt, under any pretext whatever, to reconcile or confound these two kinds of objects with each other, is to go in direct opposition to all the progress made for more than a century, and especially during the last few years, in physics, chemistry and physiology. It is inexplicable to me that some men, whose merits I otherwise acknowledge, should have recently again compared crystals to the simplest living forms, to the sarcodic organisms, as they were called by Dujardin, who discovered them, and was the first to give a comprehensive theory of them from minute observations. A change of name is useless; the things remain the same, and protoplasm has the same properties as sarcode. The animals, whose entire substance they seem to form, have not altered their nature; whether monera or amœbæ, these forms are the antipodes of the crystal from every point of view.

A crystal, as M. Naudin has well remarked, closely resembles one of those regular piles of shot which may be seen in every arsenal. It only increases from the exterior, as the pile is increased when the soldier adds a fresh layer of shot; its molecules are just as immovable as the balls of iron. It is exactly the contrary with the organised being, and the simpler its composition the greater the contrast. The small size of the moneron and the amœba prevents, it is true, certain observations. I appeal, however, to all those naturalists who have studied certain marine sponges in a living state. They must like myself have remarked the strange activity of the _vital whirlpool_ in the semi-sarcodic substance which surrounds their siliceous or horny skeleton; they will have seen the sea water in which they are placed move with a rapidity which it never exhibits when in contact with any other animal.

The reason is that, in the organised being, the repose of the crystal is replaced by an incessant movement; that, instead of remaining immovable and unalterable, the molecules are unceasingly undergoing transformation, changing their composition, producing fresh substances, retaining some and rejecting others. Far from resembling a pile of shot, the organised being may much rather be compared to the combination of a number of physico-chemical apparatus, constantly in action to burn or reduce materials borrowed from without, and ever making use of their own substance for its incessant renewal.

In other words, in the crystal once formed the forces remain in a state of _stable equilibrium_, which is only interrupted by the influence of exterior causes. Hence the possibility of its indefinite continuance without any change either of its forms or of its properties. In the organised being the equilibrium is _unstable_, or rather, there is no equilibrium properly so called. Every moment the organised being expends as much _force_ as _matter_, and owes its continuance solely to the _balance of the gain and loss_. Hence the possibility of a modification of its properties and form without its ceasing to exist.

Such are the bare facts which rest upon no hypothesis whatever; and how can we, in the presence of these facts, compare the crystal which grows in a saline solution to the germ which becomes in succession embryo, fœtus, and finally a complete animal? How can we confuse the _inanimate body_ with the _organised being_.

The two groups are easily separated by the phenomena they exhibit. It is the same with the causes of the phenomenon.

Naturalists and physiologists are here divided. Some would have it that the cause, or the causes, are identical, and that conditions, which are almost accidental, alone determine the difference in the results by changing their mode of action. In their opinion the formation of a crystal or of a moneron is only a question of resultant.

Others consider living beings as the result of a cause entirely different from those which act in inanimate bodies, and refer to this cause alone everything which takes place in these beings.

These two methods appear to me, from the exclusive element in each, to be equally ill-founded. It cannot be denied that phenomena identical with those characteristic of inanimate bodies are found in organised beings, and we have, therefore, no scientific reason to attribute them to different causes.

But organised beings have also their special phenomena radically distinct from, or even opposed to, the former. Is it possible to refer all of them to one, or to several, identical causes? I think not. For this reason, I admit with a great number of eminent men of every age and country, and, I believe, with the majority of those that respect modern science, that organised beings owe their distinctive characteristics to a _Special Cause_, to a _Special Force_, to _Life_, which in them is associated with the inorganic forces. For this reason I consider it legitimate to call them _Living Beings_.

I shall often, however, return to this class of considerations, in order to make it quite clear in what sense I take these words, _Force_, and _Life_.

III. The two Empires of Pallas are themselves sub-divided into Kingdoms, which are characterised by special facts and phenomena, becoming more and more complicated as we ascend the scale of nature.

And, in the first place, I distinctly admit with de Candolle the existence of a _Sidereal Kingdom_. To any one who considers, as far as we are able, the little that we know of the universe, the celestial bodies, suns, planets, and comets or satellites only appear as molecules of the great All which fills indefinite Space. One general phenomenon which is unchangeable, however varied in its forms, is, as it were, the attribute of these bodies. All, whether gaseous or solid, obscure or luminous, hot or cold, move within curves of the same nature, obeying the laws discovered by Kepler. It is now well known that _fixed stars_ do not exist.

In order to explain this _phenomenon_ philosophers have admitted the existence of a _force_ which they have called _Gravitation_, the effect of which is to precipitate the stars towards one another, as if they mutually attracted each other, whilst obeying the laws of Newton. Now it is well known that the great Englishman himself gave no opinion upon the mode of action of this force, and that he hesitated between the hypothesis of _Attraction_ and that of _Impulsion_. The first should prevail as being more in accordance with the immediate results of observation; but the second also has had serious partisans, among whom I will only mention M. de Tessan.

Thus Newton, in spite of all his genius, cannot tell us what was the cause of the movement of the stars; he was not even able to determine the immediate mode of action of this cause; and yet there is not a scientific term more universally received than that of _Gravitation_, there is not a case in which the expression _Force_ is more generally accepted. The reason of this is, that in the presence of general facts and groups of phenomena, it is necessary to make use of terms as simple as possible. We must, however, avoid the delusion of thinking that _naming_ is equivalent to _explaining_.

In cases analogous to that of which we have been treating, the word Force merely indicates the presence of an _Unknown Cause_, which gives rise to a _group of fixed phenomena_. In assigning names to each of the Forces or Unknown Causes to which we consider ourselves able to refer certain groups of phenomena, we facilitate the demonstration and discussion of the facts. The scientific man knows very well that he cannot go beyond this.

It is in this sense, and in this sense alone, that I have used above the expressions _Force_ and _Life_. Astronomers consider gravitation the unknown cause of the movement of the stars; I consider Life as the unknown cause of the phenomena which are characteristic of organised beings. It may be that both gravitation and Life, as well as the other general forces are merely as _x_, of which the equation has not yet been discovered. I shall presently return to these considerations.

Be this as it may, whatever our real ignorance, whatever the Cause of which we are here treating, and though _Impulsion_ should one day replace _Attraction_ in our Theories, the facts would still remain the same. The stars would still be distributed through space, and subject to the laws of Newton and Kepler; they would still constitute a perfectly distinct whole, in the part assigned to the bodies which compose it, and in the nature of the relations which unite them. They would still form the _Sidereal Kingdom_.

This kingdom is then characterised by a _general phenomenon_, the _Keplerian Movement_, which may be attributed to a single force, namely that of _gravitation_.

IV. Let us now return to the Earth, the only celestial body which we can study in detail. Modern discoveries, however, judging from the relation of the elements and their mutual action, make it almost certain that the greatest similarity exists between the stars distributed in space, between all those at least which form part of our heavens.

Let us first establish the fact that upon our globe we again meet with the Keplerian Movement in falling bodies. Attraction is here represented by _Weight_. Gravitation reappears with all its laws, acting upon grains of dust as it acts upon worlds. The parts of the whole, of cosmos, as Humboldt would have said, cannot escape from the force which governs the whole.

But upon the surface of our Earth and in its interior, as far as we have been able to penetrate either by direct observation or scientific induction, we notice the appearance of other movements which are not subject to the laws of Kepler or Newton; phenomena appear which are entirely new and perfectly distinct from those due to gravitation. They are the _physico-chemical_ phenomena. From their number and their difference in character they were long attributed to the action of distinct forces which were called _Electricity_, _Heat_, _Magnetism_, etc. Modern science, however, by transforming, so to speak, one into the other, has demonstrated their original unity. Physicists refer them all to nothing more than so many manifestations of the undulations of ether. The vibration of the latter is then the fundamental phenomenon from which all the others rise.

But this ether is absolutely hypothetical; its nature is perfectly unknown; no one knowing whence it acquires this quantity of movement, which, according to actual theory, should be subject neither to increase nor diminution. Now, in reality, we have here the _Unknown cause_ of all physico-chemical phenomena. For this reason, and also for convenience, we shall give a name to this unknown cause, to this _force_, and call it _Etherodynamy_ (Ethérodynamie).

But is not Etherodynamy only a particular form, a simple modification, or an effect of gravitation? Are not these two forces only different manifestations of a more general force? Many eminent men are much inclined to admit one or other of these hypotheses. Still, up to the present time, the facts do not seem to me to shew much agreement with them. Etherodynamy is displayed even in space and among the stars by variable, localised and temporary phenomena; the action of gravitation is one, universal and constant. Man has always been able to exercise a certain amount of control over the former; he can produce at will light and heat; modern science cannot act upon the second. We can neither augment nor diminish, reflect or refract, or polarise weight; we cannot arrest its action. Even in the fall of bodies the regularity in the acceleration of the motion proves that the cause of this movement is subject to no alteration. Here then is no _transmutation of force_ similar to that in a machine worked by electricity or heat.

But whatever be the progress of science, and though M. de Tessan’s theory should be confirmed by experiment, the difference between the phenomena would not be diminished; the conclusions to be drawn from the facts in connection with the question we are here discussing would remain the same.

It is scarcely necessary to remark that the physico-chemical phenomena produced by etherodynamy can act upon masses or be exclusively molecular. They are in all cases similar to those which depend upon gravitation, they are subject to invariable laws and are always repeated in a similar manner when produced under similar circumstances.

No antagonism, it is true, exists between gravitation and etherodynamy. It is no less true that the action of the first is always disturbed in a peculiar manner by that of the second, and that in some phenomena it seems as if the latter would neutralise the former. This fact is most strikingly shown in some of the commonest experiments in physics. The gold leaves of the electroscope separate, the pith-balls are attracted towards electrified bodies in spite of their weight, and are repelled with a rapidity greater than that which would result merely from their own weight. And yet these bodies have no more ceased to possess weight than those masses of iron raised by the powerful magnets of M. Jamin. Etherodynamy in these two cases merely overcame gravitation and either modified or imitated its action.

Those terrestrial bodies which present no other phenomena than those which can be referred to either gravitation or etherodynamy have, since the time of Linnæus, been termed _Inanimate Bodies_. Together they constitute the _Mineral Kingdom_. We see that the existence and the distinction of this group are perfectly independent of any hypothesis intended to explain the phenomena.

_Two kinds of phenomena_ then are characteristic of the mineral kingdom: _phenomena of the Keplerian movement_ and _physico-chemical phenomena_, which may be attributed to the action of two forces: _gravitation_ and _etherodynamy_.

V. The sidereal and mineral kingdoms form the Inorganic Empire. Passing from it we enter the domain of organized and living beings. We have already seen the essential phenomena by which they are distinguished. These phenomena differ essentially from all those which we have observed in inanimate bodies. It seems to me, therefore, necessary to attribute them to a special cause,—to _Life_.

I know that in the present day any one making use of this word is readily accused by a great number of physicists and chemists, and by an entire physiological school, of introducing into science a vague and almost mysterious expression. There is, however, nothing in it more vague or mysterious than in the word _gravitation_.

It is very true that we do not know _what_ Life _is_; but no more do we know _what_ the force _is_ that set the stars in motion and retains them in their orbits. If astronomers have been right in giving to the _force_, or _unknown cause_, which gives the worlds their mathematical movements, naturalists have a perfect right to designate by a special term that _unknown cause_ which produces filiation, birth and death.

It will be apparent that my idea of Life is not the same as it was with many ancient vitalists, that it is no more the _arche_ of van Helmont than the _vital principle_ of Barthez. Its function appears to me very different to that attributed to it by most of our predecessors, and which is still attributed to it by some physiologists.

Far from merely animating the organs, it is closely associated with the forces of which we have already spoken. Living beings are heavy, and therefore subject to gravitation; they are the seat of numerous and various physico-chemical phenomena which are indispensable to their existence and which must be referred to the action of etherodynamy. But these phenomena are here manifested under the influence of _another force_. It is for this reason that the results of these phenomena are often quite different to those in inanimate bodies, and that living beings have their special products. Life is not antagonistic to the inanimate forces, but it governs and rules their action by its laws. Therefore it makes them produce tissues, organs and individuals instead of crystals; it organizes germs, and maintains through space and time, in spite of the most complex metamorphoses, that _unity of definite living forms_ which we call _Species_.

If the anti-vitalists would only seriously reflect upon the matter, they would acknowledge that, considered from this point of view, there is nothing more mysterious in living beings than in some of the commonest phenomena presented by inanimate bodies. The intervention of Life as a modifying agent of actions purely etherodynamic may be as easily admitted as that of etherodynamy itself modifying and overcoming the action of weight. It is just as strange to see a piece of iron attracted and supported by a magnet, as to see carbon, oxygen, hydrogen and nitrogen combine and dispose themselves so as to form an animal or vegetable cell instead of any imaginable inorganic composition.

I have repeatedly, and for many years, maintained the doctrine which I have summed up here. It seems to me confirmed in the highest degree by the researches undertaken for the elucidation of the problem of which we are treating. The experiences of M. Bernard in particular, relative to the action exercised by anæsthetics upon plants as well as upon animals, makes it impossible for us to doubt for a moment the intervention of an agent distinct from physico-chemical forces in organic beings. In employing the word _Life_ to designate this agent, I only make use of an established expression, without pretending to go beyond the information gained from experiment and scientific observation.

Beings, in which life alone is added to gravitation and etherodynamy constitute the _Vegetable Kingdom_. Now there is one general fact displayed by this group, the significance of which has not, it seems to me, been sufficiently understood. With the exception of certain phenomena of _unconscious irritability_ which have long been known in some plants of a superior order, and of facts, probably of the same class, which have been established chiefly with reference to some reproductive organs of plants of an inferior order, every movement which takes place in plants appears to be produced _solely_ by inanimate forces. The transfer of matter in particular, which is necessary for the development and sustenance of every vegetable, belongs to actions of this kind. Can we believe that these forces, as they are known to us from innumerable experiments, could, if left to themselves, have formed an oak, or even raised a mushroom? Can we believe that they could have _organised_ the acorn or the spore, and hidden in those minute bodies the power of reproducing the parent? And yet without them the vegetable cannot exist. But, in my opinion, nothing makes their real subordination more apparent than the importance of their part in the process of execution. They may be compared to workmen raising an edifice under the eye of the architect who has made the plan.

Are we then to conclude that life is an intelligent force, conscious of the part it plays, and enjoying the dominion it exercises over the subordinate inanimate forces? Not at all. Like these forces, it is ruled by general and fixed laws. Nevertheless, we do not find in the application of these laws, and in the results to which they lead, the mathematical precision of the laws and phenomena of gravitation and etherodynamy. Their mode of action merely seems to oscillate between limits which remain impassable. This kind of liberty, and the bounds imposed upon it, are conspicuous in the constant diversity of the products of life, a diversity which contrasts in so striking a manner with the uniformity of the products of etherodynamy. Crystals, when similar in composition, and when formed under similar circumstances, resemble each other perfectly; but we never find two leaves exactly alike upon the same tree.

The vegetable kingdom is, therefore, characterised by _three kinds of phenomena_: _the Keplerian movement_, _physico-chemical phenomena_, and _vital phenomena_, which may be ascribed to the action of three forces: _Gravitation_, _Etherodynamy_, and _Life_.

VI. We find repeated among animals all the phenomena which we have noticed amongst plants, and, especially in the highest orders, those movements due to unconscious irritability, of which examples are presented by plants. Some eminent men, Lamarck among the number, have even wished to refer all acts performed by inferior animals to this order of phenomena. But here the author of _La Philosophie Zoologique_ has fallen into an anatomical error, which has been long since recognised; and whoever has lived, even for a short time, by the sea-side, or has followed closely the habits and actions of worms and zoophytes will certainly protest against this manner of regarding them.

Passing from the plant to the animal, the latter executes movements belonging either to the part or to the whole which are perfectly independent of the laws of gravitation and etherodynamy. The regulating and determining cause of these movements is evidently within the animal itself. It is the _Will_. But the Will itself is intimately connected with _sensibility_ and _consciousness_. To everyone who judges animals by what he finds takes place within himself, personal experiment and observation prove that the animal _feels_, _judges_, and _wills_, that is to say _reasons_, and consequently is _intelligent_.

This proposition will, I know, be contested by men whose learning I profoundly respect, and objections will be made on all sides. On the one hand the Automatism of Descartes will be revived in some schools, and will now be supported by physiology and the experiments of vivisection. I am far from denying the great interest which is attached to the latter, and to the phenomena of reflex actions. But the conclusions which are drawn from them appear to me singularly exaggerated; Carpenter has rightly opposed them with personal experiment. I will add that the study of animals placed far below, and certainly inferior to, the frog, would doubtless lead to very different interpretations. Moreover, Huxley himself admits that animals are probably _sensible_ and _conscious automata_. But if they were merely machines we should be obliged to allow that they performed their functions _as if_ they felt, judged, and willed.

On the other hand, in the name of philosophy and psychology, I shall be accused of confounding certain _intellectual_ attributes of the human _reason_ with the exclusively _sensitive_ faculties of animals. I shall presently endeavour to answer this criticism from the standpoint which should never be quitted by the naturalist, that, namely, of experiment and observation. I shall here confine myself to saying that, in my opinion, the animal is _intelligent_, and, although a _rudimentary_ being, its _intelligence_ is nevertheless of the _same nature_ as that of man. It is, moreover, very unequally distributed among the animal species; in this respect there are many intervening stages between the oyster and the dog.

In addition to the phenomena which spring from the intelligence and reasoning, we find in animals other impulses which arise from _Instinct_, a blind impulse, or at least apparently so, which often is the characteristic of animal species, and with which each individual is endowed. These two orders of facts are very often confounded, but the confusion can be explained as follows. In the first place, instinct has as its object the attainment of a determined and fixed result, but in the multitude of ways and means necessary to attain this result a portion which is often very large is due to the intelligence. The distinction is not always easy. It will, moreover, be apparent that I cannot here enter into the details required by the examination of this question, so entirely foreign to that which is before us.

Besides the acts of intelligence and instinct, phenomena have been established among animals which are closely connected with what we call _character_, _sentiment_, or _passion_. The familiarity of the terms is in itself a proof that upon this point ordinary observation has outstripped scientific examination.

All these phenomena are perfectly new and have no analogy with those which we have noticed in the preceding kingdoms. They evidently justify the formation of an equally important group. The _animal kingdom_ is thus universally admitted, independently of every theory which attempts to explain its characters.

Facts radically different cannot be attributed to the same cause. We must admit, then, that the characteristic phenomena of the animal depend upon something different to those met with in the vegetable or mineral kingdoms. They are, moreover, united by such intimate relations, that it would be impossible not to attribute them to a single cause. From motives already mentioned we will give a name to this _Unknown Cause_, and, making use of an expression already established, though open, I can see, to more than one criticism, we will call it the _Animal Mind_ (l’âme animale).

Does the animal mind liberate the beings it animates from the inferior forces? By no means, for we find them repeated with all their characteristics. In order to raise the least of its organs, the animal must contend with weight; it cannot perform the smallest movement without the intervention of physico-chemical phenomena; it cannot breathe, and, therefore, cannot live, without constantly consuming some of its constituents. In the animal, moreover, just as much as in the plant, the inanimate forces, etherodynamy especially, appear in their double character of constancy and of ubiquity in the accomplishment of phenomena, and of subordination to life, which governs their action in the animal as in the plant.

Moreover, a large part is reserved for purely vegetative life in animals of the highest order. The entire organism is formed without any intervention of the animal mind. Again, a certain number of organs always escape more or less from the influence of the latter, and seem to be subject to life alone. Now these organs are precisely those upon which _nutrition_, and consequently the constitution and duration of the whole, depend. Thus life, which reigned supreme in the vegetable kingdom, now in its turn, appears in a subordinate character. We might say that it was essentially entrusted with the organisation and maintenance of the instruments of the animal mind.

As to the latter, even where its intervention is most questioned, it is only revealed to observation by _voluntary movements_. Now personal experiment and the faculty of reasoning, are necessary to enable us to comprehend the nature, and appreciate the signification of these movements. It is only by regarding himself as normal, that man can judge of the animal, a subject to which I shall presently return.

_Phenomena of four kinds_ are then characteristic of the Animal Kingdom: _phenomena of the Keplerian movement_; _physico-chemical phenomena_; _vital phenomena_; and _phenomena of voluntary movement_; attributable to the action of four forces: _gravitation_, _etherodynamy_, _life_, and the _animal mind_.

VII. Although the preceding statements are so much abridged, I have thought it well to give the condensed results in the following table:

+-----+-----------+---------------+---------------------+--------------+
| | EMPIRES. | KINGDOMS. | PHENOMENA. | CAUSES. |
+-----+-----------+---------------+---------------------+--------------+
| | | {Sidereal | {Phenomena of the | |
| | | {(de Candolle)| { Keplerian movement| Gravitation. |
| | | { | | |
| |Inorganic | { | {Phenomena of the | |
| { | (Pallas).| {Mineral | { Keplerian movement| Gravitation. |
| A { | | { (Linnæus) | {Physico-chemical | |
| l { | | { | { phenomena | Etherodynamy.|
| l { | | | | |
| { | | { | {Phenomena of the | |
| { | | { | { Keplerian movement| Gravitation. |
| B { | | {Vegetable | {Physico-chemical | |
| o { | | { (Linnæus) | { phenomena | Etherodynamy.|
| d { | | { | {Vital phenomena | Life. |
| i { | | { | | |
| e { | Organic | { | {Phenomena of the | |
| s { | (Pallas).| { | { Keplerian movement| Gravitation. |
| { | | { | {Physico-chemical | |
| | | {Animal | { phenomena | Etherodynamy.|
| | | { (Linnæus) | {Vital phenomena | Life. |
| | | | {Phenomena of | |
| | | | { voluntary movement| The Animal |
| | | | | Mind. |
+-----+-----------+---------------+---------------------+--------------+

From this table, and the expansions which it sums up, rise the following conclusions.

1. Each kingdom is characterised by a certain number of phenomena, whose existence is independent of all hypothesis and theory.

2. The phenomena increase in number from the sidereal to the animal kingdom.

3. In passing from one kingdom to another, and proceeding from the simple to the composite, a number of phenomena appear, which are entirely unknown in the inferior kingdoms.

4. The superior kingdom presents, independently of its special phenomena, the characteristic phenomena of the inferior kingdoms.

5. Each group of phenomena indicated in the table is connected with a small number of fundamental phenomena, which can, in some cases with certainty, in others with more or less probability, be referred to a single cause.

6. All these causes are equally unknown to us as regards their nature and mode of action. We know them merely by phenomena. We can, therefore, make no conjecture as to the relations, more or less close, which may exist between them.

7. We nevertheless give names to these causes for the sake of convenience, and of facilitating the discussion of the facts.

VIII. We can now return to the problem which gave rise to these expansions, and ask the question: Whether Man should take his place in the animal kingdom? a question which evidently leads to another: Is man distinguished from animals by important and characteristic phenomena, absolutely unknown in the latter? For more than forty years I have answered this question in the affirmative, and my convictions, tested by many controversies, are now stronger than ever.

But it is neither in the material disposition, nor in the action of his physical organism, that we must look for these phenomena. From this point of view, man is neither more nor less than an animal. From an anatomical point of view, there is less difference between man and the superior order of apes, than between the latter and the inferior orders. The microscope reveals equally striking resemblances between the elements of the human organism and those of the animal organism; and chemical analysis leads to the same result. It was easy to foresee that the action of elements and organs would be exactly the same in man and beast, and such was found to be the case.

Passions, sentiments, and characters, establish between animals and ourselves equally close relations. The animal loves and hates; we recognise in it irritability and jealousy; unwearying patience, and immutable confidence. In our domestic species, these differences are more apparent, or perhaps we only notice them more closely. Who has not known dogs which have been playful or snappish, affectionate or savage, cowardly or courageous, friendly with everybody, or exclusive in their affections.

Again, man has true instincts, were it only that of sociability. Faculties, however, of this order, which are so fully developed in certain animals, in man are evidently very much reduced in comparison with the intelligence.

The relative development of the latter certainly establishes an enormous difference between man and animal. It is not, however, the _intensity_ of a phenomenon which gives value to it from our present point of view, but simply its _nature_. The question is whether human intelligence and animal intelligence can be considered as of the same order.

As a rule philosophers, psychologists, and theologians, have replied in the negative, and naturalists in the affirmative. This opposition can be easily understood. The former make the human mind, considered as an indivisible whole, their principal study, and attribute to it all our faculties. Unable to deny the similarity, external at least, between certain animal and human acts, and yet being anxious to clearly distinguish man from the brute, they have given to the acts different interpretations as they have been performed by one or the other. Naturalists have regarded the phenomena more closely without thinking of anything else, and when they have seen the animal behave in the same manner as they themselves would have done under the given circumstances, they have concluded that the motives of the action must be fundamentally the same. I must ask permission to remain a naturalist, and to recall some facts, and regard them from this point of view.

The theologians themselves allow that the animal possesses sensation, formation and association of images, imagination, and passion (R. P. de Bonniot). They allow that the animal feels the relation of fitness or of unfitness between sensible objects and his own senses; that it experiences sensible attractions and repulsions, and acts perfectly in consequence, and that _in this sense the animal reasons and judges_ (l’Abbé A. Lecomte). Therefore, they add, we cannot doubt but that the animal possesses a principle superior to that of mere matter, and we may even give it the name of mind (R. P. Bonniot). But in spite of all, theologians and philosophers maintain that the animal cannot be intelligent, because it has neither _innate sense_, _consciousness_ nor _reason_.

Let us leave for a moment the last term, with which the idea of phenomena which we shall presently discuss, is connected in the mind of our opponents. Is it true that animals are wanting in innate sense, and are not conscious of their actions? Upon what facts of observation does this opinion rest? We each one of us feel that we possess this sense, that we enjoy this faculty. By means of speech we can convey to another the results of our personal experience. But this source of information is wanting when we come to deal with animals. Neither in them nor in ourselves are innate sense and consciousness revealed to the outer world by any special characteristic movement. It is, therefore, only by interpreting these movements, and by judging from ourselves, that we can form an idea of the motives from which the animal acts.

Proceeding in this manner, it seems to me impossible to refuse to allow animals a certain amount of consciousness of their actions. Doubtless, they do not form such an exact estimate of them, as even an illiterate man can do. But we may be very certain that when a cat is trying to catch sparrows on level ground, and creeps along the hollows, availing herself of every tuft of grass however small, she knows what she is about, just as well as the hunter who glides in a crouching attitude from one bush to another. We may be equally sure that kittens and puppies when they fight, growl and bite without hurting each other, know very well that they are playing and not in earnest.

I must here beg permission to relate the remembrance of my struggles with a mastiff of pure breed, and which had attained its full size, remaining, however, very _young in character_. We were very good friends, and often played together. As soon as ever I assumed an attitude of defence before him, he would leap upon me with every appearance of fury, seizing in his mouth the arm which I had used as a shield. He might have marked my arm deeply at the first onset, but he never pressed it in a manner that could inflict the slightest pain. I often seized him by his lower jaw with my hand, but he never used his teeth so as to bite me. And yet the next moment the same teeth would indent a piece of wood, I tried to tear away from them.

This animal evidently knew what it was doing when it feigned the passion precisely _opposite_ to that which it really felt; when, even in the excitement of play, it retained sufficient mastery over its movements to avoid hurting me. In reality it _played a part in a comedy_, and we cannot act without being conscious of it.

It is useless for me to insist upon many other facts which I could bring forward, and I refer my reader to the works of those naturalists who have studied the question, especially those of F. Cuvier. But the more I reflect upon it, the more is my conviction confirmed that man and animals think and reason in virtue of a faculty which is common to both, and which is only far more developed in the latter than in the former.

What I have just said of the intelligence I do not hesitate to say also of language, the highest manifestation of the intelligence. It is true that man alone possesses _speech_, that is to say the _articulate voice_. But two classes of animals possess _voice_. With us it is, again, only a high degree of perfection, nothing radically new. In both cases the sounds, produced by the air which is thrown into vibration by the voluntary movements accorded to the larynx, convey impressions and personal thoughts which are understood by individuals of the same species. The mechanism of the production, the object and the result are fundamentally the same.

It is true that the language of animals is most rudimentary and, in this respect, in harmony with the inferiority of their intelligence. We might say that it was almost entirely composed of interjections. Such as it is, however, this language is sufficient for the wants of the mammalia and birds who understand it perfectly, while man himself can learn it without very much trouble. The hunter can distinguish the accents of anger, love, pleasure, sorrow, the call and the signal of alarm and makes use of these indications as an unfailing guide, and often imitates these accents and cries in such a manner as to deceive the animal. Of course I exclude from the _language of brutes_, the song, properly so called, of birds, that of the nightingale for example. It appears to me void of all meaning, as are the notes of a singer, and I do not believe in the interpretation of Dupont de Nemours.

It is not, therefore, in the phenomena connected with the intelligence that we shall find the basis of a fundamental distinction between man and animals.

But in man the existence has been proved of fundamental phenomena of which nothing either in living beings or inanimate bodies has hitherto been able to give us any conception. 1st. Man has the _perception of moral good and evil_ independently of all physical welfare or suffering. 2nd. Man _believes in superior beings_ who can exercise an influence upon his destiny. 3rd. Man _believes in the prolongation of his existence after this life_.

The last two phenomena have always been so closely connected that it is natural to refer them to the same faculty, to that namely of _Religion_. The first depends on _Morality_.

Psychologists attribute religion and morality to the _reason_, and make the latter an attribute of man. But with the _reason_ they connect the highest phenomena of the intelligence. In my opinion, in so doing they confound and refer to a common origin, facts entirely different. Thus since they are unable to recognise either morality or religion in animals, which in reality do not possess these two faculties, they are forced to refuse them intelligence also, although the same animals, in my opinion, give decisive proof of their possession of this faculty every moment.

The generality of the phenomena which we are discussing is, I believe, indisputable, especially since the investigation to which it has been subjected by the Society of Anthropology in Paris, where the question of the human kingdom has been long and seriously discussed. I cannot here reproduce the discussion, even in an abridged form, but refer my readers either to the summary in my _Rapport sur les progrès de l’anthropologie en France_, or to the _Bulletins_ of the Society. I shall, moreover, go into this subject in some detail in the chapters devoted to the moral and religious characters of the human races.

A host of manifestations of human activity are derived, as so many consequences, from the three facts which I have pointed out. Customs and institutions of every kind are connected with them; they alone explain some of the great events which change the destiny of nations and the face of the earth.

For reasons which I have several times pointed out already, we must give a name to the _Unknown Cause_ from which are derived the phenomena of morality and religion. We will call it the _Human mind_ (l’âme humaine).

I must here repeat the formal declaration which I have often made already. When I employ this term, which is established by custom, it is with the understanding that I strictly confine myself within the limits imposed upon anyone who intends to be exclusively faithful to science, experiment and observation. I consider the human principle as the _Unknown Cause_ of exclusively human phenomena. To go beyond that would be to encroach upon the domain of philosophy or theology. To them belongs the solution of the formidable problems raised by the existence of the ‘_something_’ which makes a man of an organism entirely animal, and I give everyone leave to choose from the proposed solutions the one which agrees most satisfactorily with the demands of his own feelings and reason.

But whatever this solution may be, it will in no way affect the phenomena; those which I have just described will neither be diminished nor modified. Now they exist in man alone, and it is impossible to deny their importance. Thus they distinguish man from the animal as much as the phenomena of intelligence distinguish the animal from the plant, and as the phenomena of life distinguish the plant from the mineral. They are, therefore, the attributes of a kingdom, which we will call the _Human Kingdom_.

From this conclusion it will seem that I am at variance with Linnæus, whose idea I have, however, only developed and stated more precisely. In fact, the immortal author of the _Systema Naturæ_ has placed his _Homo sapiens_ amongst the mammalia in the class of primates, and has made him congenous with the gibbon. This is because Linnæus had recourse to the _System_ in order to establish his _nomenclature_. To classify man as well as other beings, he has made an arbitrary choice of a certain number of characteristics, and only taken those into consideration which were furnished by the body.

But the language of Linnæus is very different, even in his remarks relating to the genus _Homo_, and still more so in the kind of introduction entitled _Imperium Naturæ_. He there almost places man in opposition with all beings, and particularly with animals, and in such terms as necessarily to suggest the idea of a _human kingdom_.

The reason of this is that here Linnæus no longer speaks of _physical_ man, but of man _as a whole_. Now, thanks to the labours of Adanson, Jussieu and Cuvier, naturalists now know that this is the right course to pursue in judging of the relations which exist between beings. The _Natural Method_ no longer allows the choice of such or such a group of characteristics; it demands, together with an appreciation of their relative value, a consideration of all. It is on this account that I have been led to admit the existence of this human kingdom, which has been already proposed under several appellations by some eminent men, but to which I believe myself to have given a more precise and rigorous determination.

The table given above must then be completed in the following manner:—

+--------+--------------------------------------+-------------+
| | PHENOMENA. | CAUSES. |
|--------+--------------------------------------+--------------
| | {Phenomena of the Keplerian movement | Gravitation |
| | {Physico-chemical phenomena | Etherodynamy|
|Human | {Vital phenomena | Life |
|Kingdom | {Phenomena of voluntary movement | Animal mind |
| | {Phenomena of morality and religion | Human mind |
+--------+--------------------------------------+-------------+

Thus in the human kingdom we find by the side of the phenomena which characterise it all those which we have met with in the inferior kingdoms. We are consequently forced to admit that all the _forces_ and all the _unknown causes_ to which we have attributed these effects are acting in man. From this point of view man deserves the name which has sometimes been given to him of _microcosm_.

We have seen that in the vegetable kingdom the inanimate forces perform their functions _under the control_, so to speak, of Life, which afterwards, in the animal, showed incontestable signs of its subordination to the animal mind. Life now appears under similar conditions with regard to the human mind. In the most characteristic human actions, the intelligence almost always plays the most prominent part from the executive point of view; but it is manifestly under the direction of the human mind. All legislation affects to rest upon the one foundation of morality and of justice, which is only a form of it; the immediate cause of the Crusades, of the spread of the Arabs, and the conquests of Islam, was religious fervour. The true legislator and the great leader are indeed necessarily men of high intelligence, but is it not clear that in the cases mentioned the intelligence has been placed at the service of morality or of religion, and consequently of the _Unknown Cause_ to which man owes these faculties?

But however preponderating the part claimed by this cause in acts exclusively human may be, it has nothing to do with those phenomena which have their origin in the intelligence alone. The learned mathematician who seeks by the aid of the most profound abstractions the solution of some great problem, is completely without the moral or religious sphere into which, on the contrary, the ignorant, simple-minded man enters when he struggles, suffers, or dies for justice or for his faith.

IX. It was necessary to recall all the facts and theories which I have just summed up, in order to facilitate the comprehension and the justification of the method which alone can guide us in anthropological studies.

The object of anthropology is the study of man _as a species_. It abandons the _material individual_ to physiology and medicine; the _intellectual_ and _moral individual_ to philosophy and theology. It has, therefore, its own special field of study, and on that account alone its special questions, which often could not be solved by processes borrowed from cognate sciences.

In fact, in some questions, and in some of the most fundamental ones, the difficulty lies in the interpretation of phenomena connected with those which are characteristic of all living beings. For the very reason that they are to a certain extent obscure in man, we cannot seek for an explanation of them in man, since he becomes, so to speak, the unknown quantity of the problem. An endeavour to solve the problem by the study of man, who is the object of it, would be equivalent to a mathematician representing the value of _x_ in terms of _x_ itself.

How does the mathematician proceed? He seeks in the data of the problem for a certain number of _known quantities_ equivalent to the _unknown quantity_, and by means of these quantities he determines the value of _x_.

The anthropologist must act in the same manner. But where must he seek for the known quantities which will enable him to state the equation?

The answer to this question will be found in what we have said above, and in the table of kingdoms. Man, although he has his special and exclusively human phenomena, is above all an organised and living being. From this point of view he is the seat of phenomena common to animals and plants; he is subjected to the same laws. In his physical organisation he is nothing more than an animal, somewhat superior in certain respects to the most highly developed species, but inferior in others. From this point of view he presents organic and physiological phenomena identical with those of animals in general, and of mammalia in particular; and the laws which govern these phenomena are the same in both cases.

Now plants and animals have been studied for a much longer period than man, and from an exclusively scientific point of view, without any trace of the prejudice and party feeling which often interferes with the study of man. Without having penetrated very deeply into all the secrets of vegetable and animal life, science has acquired a certain number of fixed and indisputable results which constitute a foundation of positive knowledge, and a safe starting point. It is there that the anthropologist must seek the _known quantities_ of which he may stand in need.

Whenever there is any doubt as to the nature or signification of a phenomenon observed in man, the corresponding phenomena must be examined in animals, and even in plants; they must be compared with what takes place in ourselves, and the results of this comparison accepted as they are exhibited. What is recognised as being true for other organised beings cannot but be true for man.

This method is incontestably scientific. It is similar to that of modern physiologists, who, since they are unable to experiment upon man, experiment upon animals, and form their conclusions upon the former from the latter. But the physiologist devotes his attention to the _individual_ only, and, therefore, examines little more than those groups which in their organisation approach most nearly to the being whose history he wishes to explain. The anthropologist on the contrary studies the _species_. The questions with which he has to deal are much more general, so he is forced to direct his attention to plants as well as to animals.

This method is accompanied by its criterion; it allows the control of the various, answers which are often made to one question. The means of estimation are simple and easily applied.

In anthropology, every solution to be sound, that is to say, true, should refer man in everything which is not exclusively human to the general recognised laws for other organised and living beings.

Every solution which makes or tends to make man an exception, by representing him as free from those laws which govern other organised and living beings, is unsound and false.

Again, when we reason and form our conclusions in this manner, we remain faithful to the mathematical method. To be received as true, a solution of a given problem must agree with admitted axioms, with truths previously proved. Every hypothesis which leads to results at variance with these axioms or these truths, is, on that account alone, declared false. In anthropology, the axiom or the truth which serves as a criterion is the fundamental, physical, and physiological identity of man with other living beings, with animals, with mammalia. All hypotheses at variance with this truth should be rejected.

Such are the absolute rules which have always acted as my guide in anthropological studies. I do not pretend to have invented them. I have scarcely done more than formulate what has been more or less explicitly admitted by Linnæus, Buffon, Lamarck, Blumenbach, Cuvier, the two Geoffroy St.-Hilaire, J. Müller, Humboldt, etc. But, on the one hand, my illustrious predecessors have seldom treated the subject with sufficient precision, and have too often omitted to give the reasons for their decisions. On the other hand these principles have been, and are daily forgotten by men who, in other respects, enjoy with justice the title of great authorities. As I shall be compelled to disagree with them, I thought it necessary to show clearly the general ideas which serve as a foundation for my own scientific convictions. The reader will thus be able to appreciate and discern the causes of this difference of opinion.