(born c. 490, Acragas, Sicilydied 430 BC, the Peloponnese) Greek philosopher, statesman, poet, and physiologist. All that remains of his writings are 500 lines from two poems. He held that all matter was composed of four basic ingredients: fire, air, water, and earth. Like Heracleitus, he held that two forces, love and strife, interact to bring together and separate the four substances. Believing in the transmigration of souls, he declared that salvation requires abstention from the flesh of animals, whose souls may once have inhabited human bodies.