Now, everything that I perceive out of myself and which acts upon my senses, I call matter; and those portions of matter which I conceive are united in individual beings, I call bodies. Thus all the disputes between Idealists and Materialists signify nothing to me; their distinctions between the appearance and reality of bodies being chimerical.
Hence I have acquired as certain knowledge of the existence of the universe as of my own. I next reflect on the objects of my sensations; and, finding in myself the faculty of comparing them with each other, I perceive myself endowed with an active power with which I was before unacquainted.
To perceive is only to feel or be sensible of things; to compare them is to judge of their existence. To judge of things and to be sensible of them are very different. Things present themselves to our sensations as single and detached from each other, such as they barely exist in nature: but in our intellectual comparison of them they are removed, transported as it were, from place to place, disposed on and beside each other, to enable us to pronounce concerning their difference and similitude. The characteristic faculty of an intelligent, active being is, in my opinion, that of giving a sense to the word exist. In beings merely sensitive, I have searched in vain to discover the like force of intellect; nor can I conceive it to be in their nature. Such passive beings perceive every object singly or by itself; or if two objects present themselves, they are perceived as united into one. Such beings having no power to place one in competition with, beside, or upon the other, they cannot compare them, or judge of their separate existence.
