This view, however, rests on the assumption that the total intensity of our consciousness is a constant quantity; so that when one element of it positively increases, the rest must positively--as well as relatively--diminish. And it does not appear to me that experience gives us any valid ground for making this general assumption: it rather seems that at certain times in our life intellect and feeling are simultaneously feeble; so that the same mental excitement may intensify both simultaneously.
Still it seems to be a fact that any very powerful feeling, reaching to the full intensity of which our consciousness is normally capable, is commonly diminished by a contemporaneous stroke of cognitive effort: hence it is a general difficulty in the way of exact observation of our emotions that the object cognised seems to shrink and dwindle in proportion as the cognitive regard grows keen and eager. How then are we to reconcile this with the proposition first laid down, that pleasure only exists as we are conscious of it? The answer seems to be that the mere consciousness of a present feeling--apart from any distinct representative elements--cannot diminish the feeling of which it is an indispensable and inseparable condition: but in introspective cognition we go beyond the present feeling, comparing and classifying it with remembered or imagined feelings; and the effort of representing and comparing these other feelings tends to decrease the mere presentative consciousness of the actual pleasure.
I conclude, then, that there is a real danger of diminishing pleasure by the attempt to observe and estimate it. But the danger seems only to arise in the case of very intense pleasures, and only if the attempt is made at the moment of actual enjoyment; and since the most delightful periods of life have frequently recurring intervals of nearly neutral feeling, in which the pleasures immediately past may be compared and estimated without any such detriment, I do not regard the objection founded on this danger as particularly important.
§ 4. More serious, in my opinion, are the objections urged against the possibility of performing, with definite and trustworthy results, the comprehensive and methodical comparison of pleasures and pains which the adoption of the Hedonistic standard involves. I cannot indeed doubt that men habitually compare pleasures and pains in respect of their intensity: that (_e.g._) when we pass from one state of consciousness to another, or when in any way we are led to recall a state long past, we often unhesitatingly declare the present state to be more or less pleasant than the past: or that we declare some pleasant experiences to have been ‘worth,’ and others ‘not worth,’ the trouble it took to obtain them, or the pain that followed them. But, granting this, it may still be maintained (1) that this comparison as ordinarily made is both occasional and very rough, and that it can never be extended as systematic Hedonism requires, nor applied, with any accuracy, to all possible states however differing in quality; and (2) that as commonly practised it is liable to illusion, of which we can never measure the precise amount, while we are continually forced to recognise its existence. This illusion was even urged by Plato as a ground for distrusting the apparent affirmation of consciousness in respect of _present_ pleasure. Plato thought that the apparent intensity of the coarser bodily pleasures was illusory; because these states of consciousness, being preceded by pain, were really only states of relief from pain, and so properly neutral, neither pleasant nor painful--examples of what I have called the hedonistic zero--only appearing pleasant from contrast with the preceding pain.