It may be said, however,--turning from pain to pleasure,--that the generalisation which we have been considering at any rate gives us a psychophysical basis for the ancient maxim of “avoiding excess” in the pursuit of pleasure. But we have to observe that the practical need of this maxim is largely due to the qualifications which the psychophysical generalisation requires to make it true. Thus it is especially needed in the important cases in which over-stimulation is followed by pain not at once but after an interval of varying length. _E.g._ alcoholic drinking, to many, remains pleasurable at the time up to the point of excess at which the brain can no longer perform its functions: it is “next morning” that the pain comes, or perhaps--in the case of “well-seasoned” topers--not till after many years of habitual excess. It should be noted also that it is not always the organ of which the exercise gives pleasure that also, through over-exercise, causes the pain of excess. Thus when we are tempted to eat too much, the seductive pleasure is mainly due to the nerves of taste which are not overtaxed; the pains come from the organs of digestion, whose faint, vague pleasures alone would hardly tempt the voluptuary to excess. In the case of dangerous mental excitements the penalty on excess is usually still more indirect. On the whole, granting that pleasure like virtue resides somewhere in the mean, it must be admitted that this proposition gives no practical directions for attaining it. For first, granting that both excessive and deficient activities of organs cause pain, the question still remains--as Spencer himself says--What determines in any case the lower and the higher limits within which action is pleasurable? Spencer’s answer to this question I will consider presently. But there is a question no less obvious to which he does not expressly advert, viz. why among the normal activities of our physical organs, that have counterparts in consciousness, some only are pleasurable in any appreciable degree, while many if not most are nearly or quite indifferent. It seems undeniable (_e.g._) that while tastes and smells are mostly either agreeable or disagreeable, most sensations of touch and many of sight and sound are not appreciably[144] either; and that, in the daily routine of healthy life, eating and drinking are ordinarily pleasant, while dressing and undressing, walking and muscular movements generally are practically indifferent.