Anaxagoras
Pre-Socratic philosopher who introduced Nous and explained eclipses.
Anaxagoras (c. 500 BC – c. 428 BC) was a pre-Socratic Greek philosopher born in Clazomenae, a town in Asia Minor then under Persian control. He is notable for bringing philosophy and scientific inquiry from Ionia to Athens, where he became associated with the statesman Pericles. Responding to Parmenides' claims on the impossibility of change, Anaxagoras introduced the concept of Nous (Cosmic Mind) as an ordering force and gave novel scientific accounts of natural phenomena, including a correct explanation for eclipses and the notion of panspermia.
- born
- c. 500 BC, Clazomenae
- died
- c. 428 BC, Lampsacus
- field
- Pre-Socratic philosophy, natural science
- nationality
- Greek (from Clazomenae, under Persian Empire)
- known_for
- Concept of Nous (Cosmic Mind), correct explanation of eclipses, panspermia, theory that the Sun is a fiery mass larger than the Peloponnese
Lore & Background
Anaxagoras was born in Clazomenae in the early 5th century BC, possibly into an aristocratic family. He arrived at Athens either shortly after the Persian war (in which he may have fought on the Persian side) or around 456 BC. While in Athens, he became close with Pericles. In later life, according to Diogenes Laërtius and Plutarch, he was charged with impiety and went into exile in Lampsacus; the charges may have been political, owing to his association with Pericles. Pericles reportedly spoke in his defense at trial around 450 BC, but Anaxagoras was forced to retire to Lampsacus around 434–433 BC. He died of starvation there around 428 BC. Citizens of Lampsacus erected an altar to Mind and Truth in his memory and established the annual Anaxagoreia celebration.
Reader's Guide
Anaxagoras is significant for shifting philosophical and scientific inquiry from Ionia to Athens, influencing later thinkers such as Socrates, who reportedly read his works eagerly. His concept of Nous as a cosmic ordering force addressed Parmenidean challenges to change and laid groundwork for later metaphysical thought. His scientific contributions—correct eclipse explanation, recognition that the Moon shines by reflected sunlight, and the notion of panspermia—were pioneering. Though only fragments of his book survive, preserved by Simplicius, his ideas were known to playwrights Sophocles, Euripides, and Aristophanes. He is mentioned in Plato's Phaedo and Apology, and later by Seneca, Dante (who placed him in Limbo), and Nietzsche, who admired his concept of Nous. His legacy includes the annual Anaxagoreia festival in Lampsacus and a lasting influence on natural philosophy.
Did You Know?
- Anaxagoras was the first Greek to attempt squaring the circle, working on the problem while in prison.
- He predicted the fall of a meteorite in 467 BC, according to Pliny.
- He believed the Moon had mountains and was inhabited.
- His book was reportedly available for a drachma in the Athenian marketplace.
Notable Quotes (Wikiquote)
"All things were together, infinite both in number and in smallness; for the small too was infinite." — Anaxagoras "Frag. B 1, quoted in John Burnet's Early Greek Philosophy, (1920), Chapter 6." — Anaxagoras "Frag. B 4, quoted in John Burnet's Early Greek Philosophy, (1920), Chapter 6." — Anaxagoras "Mind is infinite and self-ruled, and is mixed with nothing, but is alone itself by itself." — Anaxagoras
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