Everything has a natural explanation. The moon is not a god, but a great rock, and the sun a hot rock.

He was the first to explain that the moon shines due to reflected light from the sun. Anaxagoras wrote a book of philosophy but only fragments of the first part of this have survived through preservation in work of Simplicius of Cilicia in the sixth century AD. The heavenly bodies he asserted were masses of stone torn from the earth and ignited by rapid rotation.

Anaxagoras is famous for introducing the cosmological concept of Nous (mind) as an ordering force. He attempted to give a scientific account of eclipses meteors rainbows and the sun which he described as a fiery mass larger than the Peloponnese. According to Diogenes Laertius and Plutarch he fled to Lampsacus due to a backlash against his pupil Pericles.