A Philosophical Dictionary, Volume 06

by Voltaire

It is of great importance to observe, that these faculties of receiving ideas, retaining them, and compounding them, are among the many things of which we can give no explanation. These invisible springs of our being are of nature's workmanship, and not of our own.

Perhaps this gift of God, imagination, is the sole instrument with which we compound ideas, even those which are abstract and metaphysical.

You pronounce the word "triangle;" but you merely utter a sound, if you do not represent to yourself the image of some particular triangle. You certainly have no idea of a triangle but in consequence of having seen triangles, if you have the gift of sight, or of having felt them, if you are blind. You cannot think of a triangle in general, unless your imagination figures to itself, at least in a confused way, some particular triangle. You calculate; but it is necessary that you should represent to yourself units added to each other, or your mind will be totally insensible to the operation of your hand.

You utter the abstract terms—greatness, truth, justice, finite, infinite; but is the term "greatness" thus uttered, anything more or less, than a mere sound, from the action of your tongue, producing vibrations in the air, unless you have the image of some greatness in your mind? What meaning is there in the words "truth" and "falsehood," if you have not perceived, by means of your senses, that some particular thing which you were told existed, did exist in fact; and that another of which you were told the same, did not exist? And, is it not from this experience, that you frame the general idea of truth and falsehood? And, when asked what you mean by these words, can you help figuring to yourself some sensible image, occasioning you to recollect that you have sometimes been told, as a fact, what really and truly happened, and very often what was not so?

Have you any other notion of just and unjust, than what is derived from particular actions, which appeared to you respectively of these descriptions? You began in your childhood by learning to read under some master: you endeavored to spell well, but you really spelled ill: your master chastised you: this appeared to you very unjust. You have observed a laborer refused his wages, and innumerable instances of the like nature. Is the abstract idea of just and unjust anything more than facts of this character confusedly mixed up in your imagination?

Is "finite" anything else in your conception than the image of some limited quantity or extent? Is "infinite" anything but the image of the same extent or quantity enlarged indefinitely? Do not all these operations take place in your mind just in the same manner as you read a book? You read circumstances and events recorded in it, and never think at the time of the alphabetical characters, without which, however, you would have no notion of these events and circumstances. Attend to this point for a single moment, and then you will distinctly perceive the essential importance of those characters over which your eye previously glided without thinking of them. In the same manner all your reasonings, all your accumulations of knowledge are founded on images traced in your brain. You have, in general, no distinct perception or recollection of them; but give the case only a moment's attention, and you will then clearly discern, that these images are the foundation of all the notions you possess. It may be worth the reader's while to dwell a little upon this idea, to extend it, and to rectify it.

The celebrated Addison, in the eleven essays on the imagination with which he has enriched the volumes of the "Spectator," begins with observing, that "the sense of sight is the only one which furnishes the imagination with ideas." Yet certainly it must be allowed, that the other senses contribute some share. A man born blind still hears, in his imagination, the harmony which no longer vibrates upon his ear; he still continues listening as in a trance or dream; the objects which have resisted or yielded to his hands produce a similar effect in his head or mind. It is true that the sense of sight alone supplies images; and as it is a kind of touching or feeling which extends even to the distance of the stars, its immense diffusion enriches the imagination more than all the other senses put together.

There are two descriptions of imagination; one consists in retaining a simple impression of objects; the other arranges the images received, and combines them in endless diversity. The first has been called passive imagination, and the second active. The passive scarcely advances beyond memory, and is common to man and to animals. From this power or faculty it arises, that the sportsman and his dog both follow the hunted game in their dreams, that they both hear the sound of the horn, and the one shouts and the other barks in their sleep. Both men and brutes do something more than recollect on these occasions, for dreams are never faithful and accurate images. This species of imagination compounds objects, but it is not the understanding which acts in it; it is the memory laboring under error.

This passive imagination certainly requires no assistance from volition, whether we are asleep or awake; it paints, independently of ourselves, what our eyes have seen; it hears what our ears have heard, and touches what we have touched; it adds to it or takes from it. It is an internal sense, acting necessarily, and accordingly there is nothing more common, in speaking of any particular individual, than to say, "he has no command over his imagination."

In this respect we cannot but see, and be astonished at the slight share of power we really possess. Whence comes it, that occasionally in dreams we compose most coherent and eloquent discourses, and verses far superior to what we should write on the same subject if perfectly awake?—that we even solve complicated problems in mathematics? Here certainly there are very combined and complex ideas in no degree dependent on ourselves. But if it is incontestable that coherent ideas are formed within us independently of our will in sleep, who can safely assert that they are not produced in the same manner when we are awake? Is there a man living who foresees the idea which he will form in his mind the ensuing minute? Does it not seem as if ideas were given to us as much as the motions of our fibres; and had Father Malebranche merely maintained the principle that all ideas are given by God, could any one have successfully opposed him?