We will not then make all animals blind, nor practise the cruelty of Ulysses in the cave of Polyphemus, but spare in our inversion of the world that destructive instinct. It matters little that men and animals are not blind, provided they cannot see. We will then leave those organs untouched, but we will in return, take all light from the universe; quench like faint torches the sun and stars and all the celestial bodies, extinguish their feeblest scintillations upon the earth, the tall tapers which illumine the rich man's dwelling, and the fire kindled in the peasant's cot, the spark struck from the flint, and the pale phosphorescences emitted from the graves of the dead. Every thing is involved in obscurity, and it is as if that darkness which rested upon the face of the abyss before the Creator said: _let there be light_, were restored.
We must bear in mind that we have not, by plunging the world into such frightful obscurity, changed any one of its laws. The gigantic orbs describe as before with astonishing rapidity and admirable precision their immense orbits. Hence we infer that although we destroy smell, taste, sound, light, and colors, the world still exists, and we may without difficulty so conceive it to be. We may even destroy the sensation of touch, for it is easy to suppose that we perceive no impression by this sense. We may substitute some sensations, whose causes lie in bodies like those of heat and cold, hardness and softness, for others, without therefore believing the universe no longer to exist.
51. Let us now make another abstraction, and see what will happen. Let us destroy extension. The world resists not this trial; the stars vanish, and the earth disappears beneath our feet, distances no longer exist, and motion is an absurdity: our own body fades away and the whole universe is tumbled into nothingness, or if it continues somehow to exist, it is totally different from what we now imagine it to be.
And so indeed it is. If we abstract extension, if we do not externally realize that sensation, or idea, or whatever else it may be, which we have of it, if we do not consider it as the representation of what exists without us, every thing is overthrown: we know not what to think either of our sensations, or their relation to the objects causing them; things all go roundabout, and one basis of our cognitions fails: in vain we stretch out our arms to lay hold of some fixed point; and we ask in our trouble, if all that we perceive be only a pure illusion, if Berkeley's extravagances be true.