a distinguished Pythagorean philosopher, born, according to some, at Crotona, according to others, at Tarentum, some time during the latter half of the fifth century B.C. He was instructed in philosophy by Areas, and had for his disciples Simmias, Cebes, and Archytas, the friend of Plato, whom he taught at Thebes in Boeotia. Philolaus was the first who published a book on the Pythagorean doctrines, a treatise which Plato is said to have made use of in the composition of his Timaeus. This work of the Pythagorean seems to have consisted of three books:—1. Containing a general account of the Origin and Arrangement of the Universe; 2. An Exposition of the Nature of Numbers; 3. On the Nature of the Soul. (See Fabricius' Bibliotheca Graeca.) There is an edition of the fragments of Philolaus, by Böckh, 8vo, Berlin, 1819.