We have been dealing with hedonism in its strict form--that which makes _a_ pleasure, considered as to its intensity, certainty, etc., the end of an act. Hedonism in this form fails to unify life, and fails, therefore, to supply any standard. But the end of conduct is often stated to be the greatest possible sum of pleasures thus introducing a certain element of generality. Mill goes further and brings in the idea of quality of pleasure. Regarding the sum of pleasures the following from Sidgwick (Op. cit., p. 382; see also p. 114) gives the hedonistic statement. "The assumption is involved that all pleasures are capable of being compared qualitatively with one another and with all pains; that every feeling has a certain intensive quality, positive or negative (or perhaps zero) in respect to its desirableness and that the quantity may be known, so that each may be weighed in ethical scales against any other. This assumption is involved in the very motion of maximum happiness," as the attempt to make "as great as possible a sum of elements not quantitatively commensurable would be a mathematical absurdity." I. Sum of pleasures as the moral end. This, first, taken as criterion, comes into conflict with the hedonistic psychology of pleasure as the motive of acts; and, secondly, it requires some objective standard by means of which pleasure is to be summed, and is, in so far, a surrender of the whole hedonistic position. 1. If the object of desire is pleasure or a state of feeling which exists only as it is felt, it is impossible that we should desire a greatest sum of pleasures. We can desire a pleasure and that only. It is not even possible that we should ever desire a continuous series of pleasures. We can desire one pleasure and when that is gone, another, but we can not unify our desires enough to aim at even a sum of pleasures. This is well put by Green (Op. cit, p. 236). "For the feeling of a pleased person, or in relation to his sense of enjoyment, pleasure cannot form a sum. However numerous the sources of a state of pleasant feeling, it is one and is over before another can be enjoyed. It and its successors can be added together in thought, but not in enjoyment or in imagination of an enjoyment. If the desire is only for pleasure, _i. e._, for an enjoyment or feeling of pleasure, we are simply victims of words when we talk of desire for a sum of pleasures, much more when we take the greatest imaginable sum to be the most desirable." See the whole passage, pp. 235-246.