Aristotle was born in 384BC. For twenty years he studied at Athens at the Academy of Plato, on whose death in 347 he left, and some time later became tutor to Alexander the Great. On Alexander's succession to the throne of Macedonia in 336, Aristotle returned to Athens and established his school and research institute, the Lyceum. After Alexander's death he was driven out of Athens and feld to Chalcis in Euboea where he died in 322. His writings profoundly affected the whole course of ancient and medieval philosophy. HUGH LAWSON-TANCRED was born in 1955 and educated at Eton and Balliol College, Oxford. He is a Departmental Fellow in the Department of Philosophy at Birkbeck College in the University of London. He has published extensively on Aristotle and Plato and is currently engaged in research in computational linguistics. He translates widely from the Slavonic and Scandinavian languages. He is married with a daughter and two sons and lives in North London and Somerset.