From the days of Aristippus and Epicurus to our own times the nature of pleasure has occupied the attention of philosophers. 'Is pleasure an evil? a good? the only good?' are the simple forms which the enquiry assumed among the Socratic schools. But at an early stage of the controversy another question was asked: 'Do pleasures differ in kind? and are some bad, some good, and some neither bad nor good?' There are bodily and there are mental pleasures, which were at first confused but afterwards distinguished. A distinction was also made between necessary and unnecessary pleasures; and again between pleasures which had or had not corresponding pains. The ancient philosophers were fond of asking, in the language of their age, 'Is pleasure a "becoming" only, and therefore transient and relative, or do some pleasures partake of truth and Being?' To these ancient speculations the moderns have added a further question:--'Whose pleasure? The pleasure of yourself, or of your neighbour,--of the individual, or of the world?' This little addition has changed the whole aspect of the discussion: the same word is now supposed to include two principles as widely different as benevolence and self-love. Some modern writers have also distinguished between pleasure the test, and pleasure the motive of actions. For the universal test of right actions (how I know them) may not always be the highest or best motive of them (why I do them). Socrates, as we learn from the Memorabilia of Xenophon, first drew attention to the consequences of actions. Mankind were said by him to act rightly when they knew what they were doing, or, in the language of the Gorgias, 'did what they would.' He seems to have been the first who maintained that the good was the useful (Mem.). In his eagerness for generalization, seeking, as Aristotle says, for the universal in Ethics (Metaph.), he took the most obvious intellectual aspect of human action which occurred to him. He meant to emphasize, not pleasure, but the calculation of pleasure; neither is he arguing that pleasure is the chief good, but that we should have a principle of choice. He did not intend to oppose 'the useful' to some higher conception, such as the Platonic ideal, but to chance and caprice. The Platonic Socrates pursues the same vein of thought in the Protagoras, where he argues against the so-called sophist that pleasure and pain are the final standards and motives of good and evil, and that the salvation of human life depends upon a right estimate of pleasures greater or less when seen near and at a distance. The testimony of Xenophon is thus confirmed by that of Plato, and we are therefore justified in calling Socrates the first utilitarian; as indeed there is no side or aspect of philosophy which may not with reason be ascribed to him--he is Cynic and Cyrenaic, Platonist and Aristotelian in one. But in the Phaedo the Socratic has already passed into a more ideal point of view; and he, or rather