A good statement of strict individualistic hedonism is the following from Barratt, Physical Ethics, page 71: "If man aims at pleasure merely by the physical law of action, that pleasure must evidently be ultimately his own, and whether it be or not preceded by phenomena which he calls the pain and pleasure of others, is a question not of principle but of detail, just as the force of a pound weight is unaltered whether it be composed of lead or of feathers, or whether it act directly or through pulleys."
Hedonism holds that pleasure is both the natural end and the proper criterion of action:
The following quotation from Bentham (Principles of Morals and Legislation, Works, Vol. I, p. 1) gives a statement of both these elements. "Nature has placed man under the governance of two sovereign masters, pain and pleasure. It is for them alone to point out what we ought to do, [i. e. they are criteria] as well as to determine what we shall do [motives]. On the one hand, the standard of right or wrong [criterion]; on the other the chain of causes and effects [motives], are fastened to their throne."
1. _Pleasure as Criterion._ That the tendency of an action to produce pleasure is the standard for judging its moral value is generally held by the hedonists to be so axiomatic as to be beyond argument.
See Bain, Moral Science, p. 27. "The ultimate data must be accepted as self-evident: they have no higher authority than that mankind generally are disposed to accept them.... Now there can be no proof offered for the position that happiness is the proper end of all human pursuits, the criterion of all right conduct. It is an ultimate or final assumption to be tested by reference to the individual judgment of mankind." So Bentham, Enquiry I, II, "The principle is not susceptible of direct proofs for that which is used to prove everything else can not itself be proved; a chain of proofs must have their commencement somewhere." Mill, Utilitarianism. (Dissertations and Discussions, pp. 348-349). "The only proof capable of being given that an object is visible is that people actually see it. In like manner the sole evidence it is possible to produce that anything is desirable is that people do actually desire it." See Stephen, Science of Ethics, p. 42; Spencer, Data of Ethics, pp. 30-32 and p. 46; Lotze, Practical Philosophy, pp. 18-19: Sidgwick, Methods of Ethics, pp. 368-369.