History of Western Philosophy - Bertrand Russell [372]
The argument about the hot and cold hands in lukewarm water, strictly speaking, would only prove that what we perceive in that experiment is not hot and cold, but hotter and colder. There is nothing to prove that these are subjective.
In regard to tastes, the argument from pleasure and pain is repeated: Sweetness is a pleasure and bitterness a pain, therefore both are mental. It is also urged that a thing that tastes sweet when I am well may taste bitter when I am ill. Very similar arguments are used about odours: since they are pleasant or unpleasant, 'they cannot exist in any but a perceiving substance or mind'. Berkeley assumes, here and everywhere, that what does not inhere in matter must inhere in a mental substance, and that nothing can be both mental and material.
The argument in regard to sound is ad hominem. Hylas says that sounds are 'really' motions in the air, and Philonous retorts that motions can be seen or
felt, not heard, so that 'real' sounds are inaudible. This is hardly a fair argument, since percepts of motion, according to Berkeley, are just as subjective as other percepts. The motions that Hylas requires will have to be unperceived and imperceptible. Nevertheless it is valid in so far as it points out that sound, as heard, cannot be identified with the motions of air that physics regards as its cause.
Hylas, after abandoning secondary qualities, is not yet ready to abandon primary qualities, viz. Extension, Figure, Solidity, Gravity, Motion, and Rest. The argument, naturally, concentrates on extension and motion. If things have real sizes, says Philonous, the same thing cannot be of different sizes at the same time, and yet it looks larger when we are near it than when we are far off. And if motion is really in the object, how comes it that the same motion may seem fast to one and slow to another? Such arguments must, I think, be allowed to prove the subjectivity of perceived space. But this subjectivity is physical: it is equally true of a camera, and therefore does not prove that shape is 'mental'. In the second Dialogue Philonous sums up the discussion, so far as it has gone, in the words: 'Besides spirits, all that we know or conceive are our own ideas.' He ought not, of course, to make an exception for spirits, since it is just as impossible to know spirit as to know matter. The arguments, in fact, are almost identical in both cases.
Let us now try to state what positive conclusions we can reach as a result of the kind of argument inaugurated by Berkeley.
Things as we know them are bundles of sensible qualities: a table, for example, consists of its visual shape, its hardness, the noise it emits when rapped, and its smell (if any). These different qualities have certain contiquities in experience, which lead common sense to regard them as belonging to one 'thing', but the concept of 'thing' or 'substance' adds nothing to the perceived qualities, and is unnecessary. So far we are on firm ground.
But we must now ask ourselves what we mean by 'perceiving'. Philonous maintains that, as regards sensible things, their reality consists in their being perceived; but he does not tell us what he means by perception. There is a theory, which he rejects, that perception is a relation between a subject and a percept. Since he believed the ego to be a substance, he might well have adopted this theory; however, he decided against it. For those who reject the notion of a substantial ego, this theory is impossible. What, then, is meant by calling something a 'percept'? Does it mean anything more than that the something in question occurs? Can we turn Berkeley's dictum round, and instead of saying that reality consists in being perceived, say that being perceived consists in being real? However this may be, Berkeley holds it logically possible that there should be unperceived things, since he holds that some real things, viz. spiritual substances, are unperceived. And it seems obvious that, when we say that an event is perceived, we mean something more than that it occurs.
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