Then again, we find that there is the same sense and feeling of cold as of heat; but privation is neither to be seen, heard, or felt, neither is it known to any of the other senses. For the object of sense is substance; but where no substance appears, there we understand privation to be,—which is a negation of substance, as blindness of sight, silence of voice, and vacuity of corporeal substance. For there is no sense or perception of vacuity by feeling; but where there is no body to be felt, there a vacuity is implied. Neither do we hear silence; but where we do not hear any thing at all, there we imply silence. In like manner we have no perception of blindness, nakedness, or being unarmed; but we know them from the negation of our sense. Therefore if cold were a privation of heat, there would be no being sensible of cold; but only where heat ceased to be, there cold would be implied. But if, as heat is perceptible by the warmth and laxative softness of the flesh, so cold is no less perceptible by the contraction and condensation of it, it is from thence apparent, that there is some peculiar original and fountain of cold as well as heat.