Philosophical Dictionary, by Voltaire


What a pity and what a poverty of spirit to assert that beasts are machines deprived of knowledge and sentiment, which effect all their operations in the same manner, which learn nothing, never improve, etc.

What! this bird, who makes its nest in a semicircle when he attaches it to a wall; and in a circle on a tree — this bird does all in the same blind manner! The hound, which you have disciplined for three months, does he not know more at the end of this time than he did before? Does the canary, to which you play an air, repeat it directly? Do you not employ a considerable time in teaching it? Have you not seen that he sometimes mistakes it, and that he corrects himself?

Is it because I speak to you that you judge I have sentiment, memory, and ideas? Well, suppose I do not speak to you; you see me enter my room with an afflicted air, I seek a paper with disquietude, I open the bureau in which I recollect to have shut it, I find it and read it with joy. You pronounce that I have felt the sentiment of affliction and of joy; that I have memory and knowledge.

Extend the same judgment to the dog who has lost his master, who has sought him everywhere with grievous cries, and who enters the house agitated and restless, goes upstairs and down, from room to room, and at last finds in the closet the master whom he loves, and testifies his joy by the gentleness of his cries, by his leaps and his caresses.

Some barbarians seize this dog, who so prodigiously excels man in friendship, they nail him to a table and dissect him living to show the mesenteric veins. You discover in him the same organs of sentiment which are in yourself. Answer me, machinist, has nature arranged all the springs of sentiment in this animal that he should not feel? Has he nerves, and is he incapable of suffering? Do not suppose this impertinent contradiction in nature.

But the masters of this school ask, what is the soul of beasts? I do not understand this question. A tree has the faculty of receiving in its fibres the sap which circulates, of evolving its buds, its leaves, and its fruits. You will ask me what is the soul of this tree? It has received these gifts. The animal has received those of sentiment, memory, and a certain number of ideas. Who has bestowed these gifts; who has given these faculties? He who has made the herb of the field to grow, and who makes the earth gravitate towards the sun.

The souls of beasts are substantial forms, says Aristotle; and after Aristotle, the Arabian school; and after the Arabian school, the Angelical school; and after the Angelical school, the Sorbonne; and after the Sorbonne, every one in the world.

The souls of beasts are material, exclaim other philosophers. These have not been more fortunate than the former. They are in vain asked what is a material soul? They say that it is a matter which has sensation; but who has given it this sensation? It is a material soul, that is to say, it is composed of a matter which gives sensation to matter. They cannot get out of this circle.

Listen to one kind of beasts reasoning upon another; their soul is a spiritual being, which dies with the body; but what proof have you of it? What idea have you of this spiritual being, which has sentiment, memory, and its share of ideas and combinations, but which can never tell what made a child of six years old? On what ground do you imagine that this being, which is not corporeal, perishes with the body? The greatest beasts are those who have suggested that this soul is neither body nor spirit — an excellent system! We can only understand by spirit something unknown, which is not body. Thus the system of these gentlemen amounts to this, that the soul of beasts is a substance which is neither body, nor something which is not body. Whence can proceed so many contradictory errors? From the custom which men have of examining what a thing is before they know whether it exists. They call the speech the effect of a breath of mind, the soul of a sigh. What is the soul? It is a name which I have given to this valve which rises and falls, which lets the air in, relieves itself, and sends it through a pipe when I move the lungs.

There is not, then, a soul distinct from the machine. But what moves the lungs of animals? I have already said, the power that moves the stars. The philosopher who said, “Deus est anima brutorum,” — God is the soul of the brutes — is right; but he should have gone much further.

Last updated Sunday, March 27, 2016 at 12:01