CRITOLAUS, Greek philosopher, was born at Phaselis in the 2nd century B.C. He lived to the age of 82 and died probably before III B.C. He studied philosophy under Aristo of Ceos and became one of the leaders of the Peripatetic school. In general he was an orthodox Peripatetic (cf. Cicero, De Fin. v. 5), though in some respects he went beyond his predecessors. For example, he held that pleasure is an evil (Gellius, Noctes Atticae, ix. 5. 6), and definitely maintained that the soul consists of aether. The end of existence was to him the general perfection of the natural life. Cicero says in the Tusculans that the goods of the soul en tirely outweighed for him the other goods ("tantum propendere illam bonorum animi lancem") . Further, he defended against the Stoics the Peripatetic doctrine of the eternity of the world and the indestructibility of the human race. Of the life of Crit olaus one incident alone is preserved. He was sent with Car neades and Diogenes to Rome in 156-155 B.c. to protest against the fine of 500 talents imposed on Athens (Cic. Acad. [ii] 45) The three ambassadors lectured on philosophy in Rome and Cato had them dismissed from the city.
Consult the article PERIPATETICS and histories of ancient philosophy, e.g., Zeller.