Philosophical Dictionary, by Voltaire


The following passage is found in the “Système de la Nature,” London edition, page 84: “We ought to define life, before we reason concerning soul; but I hold it to be impossible to do so.”

On the contrary, I think a definition of life quite possible. Life is organization with the faculty of sensation. Thus all animals are said to live. Life is attributed to plants, only by a species of metaphor or catachresis. They are organized and vegetate; but being incapable of sensation, do not properly possess life.

We may, however, live without actual sensation; for we feel nothing in a complete apoplexy, in a lethargy, or in a sound sleep without dreams; but yet possess the capacity of sensation. Many persons, it is too well known, have been buried alive, like Roman vestals, and it is what happens after every battle, especially in cold countries. A soldier lies without motion, and breathless, who, if he were duly assisted, might recover; but to settle the matter speedily, they bury him.

What is this capacity of sensation? Formerly, life and soul meant the same thing, and the one was no better understood than the other; at bottom, is it more understood at present?

In the sacred books of the Jews, soul is always used for life.

“Dixit etiam Deus, producant aquæ reptile animæ viventis.” (And God said, let the waters bring forth abundantly the moving creature which hath a living soul.)

Creavit Deus cete grandia, et omnem animam viventem, atque motabilem quam produxerant aquæ.” (And God created great dragons (tannitiim), and every living soul that moveth, which the waters brought forth.) It is difficult to explain the creation of these watery dragons, but such is the text, and it is for us to submit to it.

Producat terra animam viventem in genere suo, jumenta et reptilia.” (Let the earth produce the living soul after its kind, cattle and creeping things.)

“Et in quibus est anima vivens, ad vescendum.” (And to everything wherein there is a living soul [every green herb], for meat.)

“Et inspiravit in faciem ejus spiraculum vitæ, et factus est homo in animam viventem.” (And breathed into his nostrils the breath of life, and man became a living soul.)

Sanguinem enim animarum vestrarum requiram de manu cunctarum betiarum, et de manu hominis,” etc. (I shall require back your souls from the hands of man and beast.)

Souls here evidently signify lives. The sacred text certainly did not mean that beasts had swallowed the souls of men, but their blood, which is their life; and as to the hands given by this text to beasts, it signifies their claws.

In short, more than two hundred passages may be quoted in which the soul is used for the life, both of beasts and man; but not one which explains either life or soul.

If life be the faculty of sensation, whence this faculty? In reply to this question, all the learned quote systems, and these systems are destructive of one another. But why the anxiety to ascertain the source of sensation? It is as difficult to conceive the power which binds all things to a common centre as to conceive the cause of animal sensation. The direction of the needle towards the pole, the paths of comets, and a thousand other phenomena are equally incomprehensible.

Properties of matter exist, the principle of which will never be known to us; and that of sensation, without which there cannot be life, is among the number.

Is it possible to live without experiencing sensation? No. An infant which dies in a lethargy that has lasted from its birth has existed, but not lived.

Let us imagine an idiot unable to form complex ideas, but who possesses sensation; he certainly lives without thinking, forming simple ideas from his sensations. Thought, therefore, is not necessary to life, since this idiot has lived without thinking.

Hence, certain thinkers think that thought is not of the essence of man. They maintain that many idiots who think not, are men; and so decidedly men as to produce other men, without the power of constructing a single argument.

The doctors who maintain the essentiality of thought, reply that these idiots have certain ideas from their sensation. Bold reasoners rejoin, that a well-taught mind possesses more consecutive ideas, and is very superior to these idiots, whence has sprung a grand dispute upon the soul, of which we shall speak — possibly at too great a length — in the article on “Soul.”

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