Berkeley's Denial of Material Substance

i. Preliminary Clarification. Before considering Berkeley's arguments it will be wise to ask what is commonly understood by 'material substance,' and in what sense Berkeley denied its existence. For he always maintains that he is denying only the theories of certain scientists or philosophers, e.g., the Newtonians, Descartes, and Locke. He asserts that his own view admits the existence of all that plain men understand by 'bodies' or 'material things'. It will also be wise to clear up beforehand the notions of 'perception' and 'sensation'. These preliminaries will take up a considerable part of the paper. I.i. What do we understand by a 'material thing'? It is always dangerous for philosophers to dogmatise about the opinions of plain men. What one ascribes to them is in fact an inference, drawn partly from one's introspection of oneself in one's 'plainer' moments, and partly from the phraseology of everyday speech in the few languages with which one is familiar. There is always a risk of putting into the mouths of babes and of sucklings what could have occurred only to the wise and prudent. But, provided that one is alive to the risks that one is taking, there is no great harm in taking them. It seems to me that a plain man means by a 'solid body' or a 'bit of matter' something which has all the following characteristics. (i) It is literally extended. It is bounded by a closed surface and has an outside and a front. (2) It is literally pervaded throughout its volume and over its surface with certain extensible qualities, e.g., colors, temperature, roughness or smoothness, and so on. (3) It is a centre from which there emanate certain sensible 'atmospheres', which form a kind of aura about it, e.g., a characteristic field of sound in the case of a tolling bell or a waterfall, a characteristic field of odour in the case of an apple, a field of sensible warmth in the case of a radiator, and so on. (4) Some of the qualities mentioned under