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AR'ISTIP'PUS (Gk. Άριστιππος, Aristippos). The founder of the Cyrenaic or Hedonistic School of Philosophy. He was the son of Aristades of Cyrene, in Africa, and was born probably not long before B.C. 435. He was drawn to Athens by the fame of Socrates, whose pupil he remained until his master's condemnation and death, without, however, adopting fully his philosophy. After Socrates's death he lived in various cities, avoiding all hindering connections by becoming a citizen of no state, but having guest-friends in many. We know that he sojourned some time in Ægina, in Corinth, where he was intimate with the famous courtesan Laϊs, and especially at the Syracusan court. He must have spent considerable time also in his native Cyrene, where he possessed property, for his philosophic school was there established. His master, Socrates, had taught that virtue and felicity together formed the highest aim of man; the latter Aristippus emphasized as a principle in itself, and declared that pleasure (ήδονή, hëdonë) was the supreme good. According to him, our sensations alone are the real bases of knowledge, and all that gives pleasant sensations must be good; virtue and all so-called moral obligations and limitations have no validity so far as they limit pleasure. Yet Aristippus shows the influence of Socratic doctrine when he teaches that the wise man will wish to preserve the enjoyment he may secure by practicing self-control, judgment, and moderation; and for the same end will resist the mastery of the passions. Further, the greatest pleasure is to be found in the cultivation of the mind. For this teaching he has been not inaptly named a pseudo-Socratic.

Many anecdotes about Aristippus have come down from antiquity. They show him to have been a skillful man of the world, capable of adapting himself to the changes of fortune. Plato is reported to have said that Aristippus was the only man he knew who could wear with equal grace both fine clothes and rags. Diogenes Laërtius has preserved to us many of his bon-mots and repartees. He apparently did not formulate a philosophy himself; the Cyrenaic system was probably worked out by Arete, his daughter, and by her son, Aristippus the younger. (See Hedonism.) Aristippus's works, if he left any, have been lost: the five letters to which his name is attached are unquestionably spurious. Consult: Zeller, Geschichte der griechischen Philosophie (Leipzig, 1893), and Ueberweg, History of Philosophy, English translation (New York, 1877).