It should be observed that if this definition of pleasure be accepted, and if, as before proposed, ‘Ultimate Good’ be taken as equivalent to ‘what is ultimately desirable,’ the fundamental proposition of ethical Hedonism has chiefly a negative significance; for the statement that ‘Pleasure is the Ultimate Good’ will only mean that nothing is ultimately desirable except desirable feeling, apprehended as desirable by the sentient individual at the time of feeling it. This being so, it may be urged against the definition that it could not be accepted by a moralist of stoical turn, who while recognising pleasure as a fact refused to recognise it as in any degree ultimately desirable. But I think such a moralist ought to admit an implied judgment that a feeling is _per se_ desirable to be inseparably connected with its recognition as pleasure; while holding that sound philosophy shows the illusoriness of such judgments. This, in fact, seems to have been substantially the view of the Stoic school. However this may be, I conceive that the preference which pure Hedonism regards as ultimately rational, should be defined as the preference of feeling valued merely as feeling, according to the estimate implicitly or explicitly made by the sentient individual at the time of feeling it; without any regard to the conditions and relations under which it arises. Accordingly we may state as the fundamental assumption of what I have called Quantitative Hedonism,--implied in the adoption of “greatest surplus of pleasure over pain” as the ultimate end,--that all pleasures and pains, estimated merely as feelings, have for the sentient individual cognisable degrees of desirability, positive or negative; observing further, that the empirical method of Hedonism can only be applied so far as we assume that these degrees of desirability are definitely given in experience. There is one more assumption of a fundamental kind, which is not perhaps involved in the acceptance of the Hedonistic calculus considered as purely theoretical, but is certainly implied if it be put forward as a practical method for determining right conduct: the assumption, namely, that we can by foresight and calculation increase our pleasures and decrease our pains. It may perhaps be thought pedantic to state it formally: and in fact no one will deny that the conditions upon which our pleasures and pains depend are to some extent cognisable by us and within our own control. But, as we shall see, it has been maintained that the practice of Hedonistic observation and calculation has an inevitable tendency to decrease our pleasures generally, or the most important of them: so that it becomes a question whether we can gain our greatest happiness by seeking it, or at any rate by trying to seek it with scientific exactness.