Anaxagoras

Anaxagoras (Greek: Ἀναξαγόρας, Anaxagoras, "lord of the assembly"; c. 500 BC – 428 BC) was a Pre-Socratic Greek philosopher. Born in Clazomenae in Asia Minor, Anaxagoras was the first philosopher to bring philosophy from Ionia to Athens. 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.

Anaxagoras is famous for introducing the cosmological concept of Nous (mind), as an ordering force. He regarded material substance as an infinite multitude of imperishable primary elements, referring all generation and disappearance to mixture and separation respectively.

All things have existed from the beginning. But originally they existed in infinitesimally small fragments of themselves, endless in number and inextricably combined. All things existed in this mass, but in a confused and indistinguishable form. There were the seeds (spermata) or miniatures of wheat and flesh and gold in the primitive mixture; but these parts, of like nature with their wholes (the homoiomereiai of Aristotle), had to be eliminated from the complex mass before they could receive a definite name and character. Mind arranged the segregation of like from unlike; panta chremata en omou eita nous elthon auta diekosmese.