ARCESILAUS, a Grecian philosopher, who is dis tinguished as the founder of the middle academy. He was a native of -Eons, and born in the first year of the 116th Olympiad, or the 516th year B. C. At Athens, whither he was carried by the love of science, he had the advantage of studying under Aristotle, Theophrastus, Polemo, and Crantor ; with the latter of whom, as well as with Zeno, the founder of the Stoic sect, he formed an intimate friendship. After the death of Crates, he succeeded to the academic chair ; and having made cer tain innovations in the Platonic doctrines, is considered as the founder of a new school, called the Middle Aca denzy.
Plato had taught that true science is conversant, not with the objects which are exhibited to our senses, but with the pure objects of intellect, which have existed from eternity as ideas, or forms, in the divine under standing. From this it was an inference, that no cer tain knowledge can be derived from merely sensible ob jects. Arcesilaus carried the scepticism of the academy a degree farther, by maintaining, that whatever certainty there may be in the nature of things, every thing is uncertain to the human tffiderstanding. That truth has no certain characters by which it may be distinguished from error ; and, consequently, that opposite opinions may be supported by arguments of equal weight. He disputed against the testimony of the senses, and the au thority of reason, but at the same time allowed that they are capable of furnishing probable opinions, sufficient for the conduct of life.
Arcesilaus was possessed of wealth, of which he made a liberal and benevolent use. Having lent some silver vessels to a friend for an entertainment, when he found that he was poor, he would not allow them to be re turned. Visiting a sick friend whom he observed to be in straitened circumstances, he silently conveyed a purse of gold under his pillow. When the sick man dis covered it, he said, with a smile, "This is one of the generous frauds of Arcesilaus." This liberality, com bined with the urbanity and sweetness of his manners, procured him many followers. But, like Aristippus, he was more addicted to luxury and splendour than was consistent with the character of a philosopher. On this account, he was scarcely entitled to the compliment of Cleanthes the Stoic, who said of him, " that, though he destroyed morals by his doctrines, he established them by his conduct." On hearing this compliment, Arce silaus said, " Cleanthes, you flatter me." " Is this flat tery," rejoined Cleanthes, "to assert that you say one thing and do another ?" He is said to have died at the age of 75, a martyr to excess. The Athenians, how over, honoured his memory by a magnificent funeral. None of his writings remain. See Dios-. Leer!. I. 4.
ilthen. 1.7. Cic. 4cad. guest. 1. 1. Cic. De Finibus, lib. 2. cap. t. Persius, 3. y. 78. Lactant. Inst. lib. iii. Blucher's and Enfield's Rist. of Philosophy, vol. 1. p. 244. (m)