In endeavoring to establish such a theory, we must start from the ordinary consciousness. What does the plain man believe about perception and the real world of physical things? He believes that his senses, especially sight and touch, put him in immediate relation with real things. He has only to open his eyes or to stretch out his hand, and he is face to face or in actual contact with the realities themselves. The objects which he perceives are not dependent upon his perceiving them, which is a purely accidental fact both in their life-history and in his. Just as he himself existed as a real being before the act of perception, so they existed independently before he turned his eyes upon them, and they continue to exist after his vision is averted. He believes, in short, that he sees and touches the real thing as that exists in itself independent of perception. He draws no distinction between the existence of the thing in itself and its existence for him in the moment of perception. The appearance is the reality. "The vulgar," as Hume says, "confound perceptions and objects, and attribute a distinct continued existence to the very things they feel or see."[1] "'Tis certain," he says again, "that almost all mankind, and even philosophers themselves, for the greatest part of their lives, take their perceptions to be their only objects, and suppose that the very being, which is intimately present to the mind, is the real body or material existence. 'Tis also certain that this very perception or object is supposed to have a continued, uninterrupted being, and neither to be annihilated by our absence nor to be brought into existence by our presence."[2]
No doubt this is, as Hume says, the belief of "the vulgar"; it is what Mr. Spencer calls Crude, and what other writers call naïve or uncritical Realism. As such, it contains much that is untenable, and much that requires more careful sifting and definition. But what we have to note is that it is a primary, instinctive, and irresistible belief of all mankind, nay of the whole animal creation. Hume himself characterizes Realism as "a natural instinct or prepossession" which operates "without any reasoning or even almost before the use of reason." [3]
