The human species

by A. de Quatrefages

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.