c. 500-c. 428 B.C.

Greek Philosopher and Astronomer

The first professional philosopher to teach in Athens, Anaxagoras introduced Ionian physical speculation to mainland Greece. He correctly explained the phases of the Moon as well as the eclipses of both the Sun and Moon. He was also the first to clearly distinguish between mind and matter.

According to the most commonly adopted chronology of his life, Anaxagoras was born in Clazomenae around 500 B.C. This Greek colony in Asia Minor was 75 miles (121 km) north of Miletus—home of Thales (c. 625-c. 547 B.C.) and Anaximander (c. 610-c. 546 B.C.). Born to a wealthy family, Anaxagoras devoted himself to the study of natural philosophy. In either 480 or 456 B.C. he settled in Athens and established a school. He was a member of the enlightened and skeptical circle that gathered around Pericles (d. 429 B.C.). He was...