# Ouspensky Pyotr Demianovich Ouspensky (1878-1947), Russian philosopher and interpreter of his guru, G.I. Gurdjieff Being attracted to theosophy early in his life, he published several books one of which was titled Tertinum Organum (Third Work) which covered such topics as time, space, the cosmos and Eastern and Western philosophies. It was at this same time that he became associated with Gurdjieff and became a disciple of his until 1924. From then on, Ouspensky conducted lectures in England while continuing to write until his death in 1947. See also Gurdjieff in this glossary.