The Greek philosopher Heracleides Ponticus (Heraclides of
Pontus), c.390-310 BC, was one of the first to propose that the
Earth rotates on its axis. He was a pupil and assistant at
Plato's Academy in Athens, later opening his own school in
Pontus. Heracleides also propounded a variant of the standard
GEOCENTRIC WORLD SYSTEM, whereby the Sun revolves about
the Earth and the planets Mercury and Venus revolve
around the Sun. Although the theory was not accepted, it was a step
toward the HELIOCENTRIC WORLD SYSTEM advanced by
ARISTARCHUS a century later.
Steven J. Dick
Bibliography: Clagett, Marshal', Greek Science in Antiquity (1955);
Sarton, George, A History of Science (1952).