Anaxagoras
Pre-Socratic philosopher who introduced Cosmic Mind and explained eclipses.
Anaxagoras was a pre-Socratic Greek philosopher born in the town of Clazomenae in Asia Minor, at a time when that region was under Persian control. He later came to Athens, where he became closely associated with the prominent statesman Pericles. In his later years, he was charged with impiety—a charge that may have been politically motivated due to his connection to Pericles, or possibly fabricated by later biographers. Pericles is said to have spoken in his defense, but Anaxagoras was nonetheless forced into exile in Lampsacus, where he died around 428 BC. The citizens of Lampsacus honored him by erecting an altar to Mind and Truth, and established an annual celebration called the Anaxagoreia.
Responding to Parmenides’ arguments against the possibility of change, Anaxagoras proposed that the world is a mixture of primary, imperishable ingredients. Material variation arises not from the absolute presence of any one ingredient, but from its relative preponderance over others. He introduced the concept of Nous, or Cosmic Mind, as an ordering force that set the original homogeneous mixture into motion, separating and arranging it. He also provided scientific accounts of natural phenomena: he correctly explained eclipses, described the Sun as a fiery mass larger than the Peloponnese, and speculated that the Sun might be just another star. He believed the Moon reflected sunlight, that it had mountains, and that it might be inhabited. He introduced the notion of panspermia, the idea that life exists throughout the universe and can be distributed everywhere. He also attempted to explain rainbows and meteors, and thought the Earth was flat, floating on strong air, with earthquakes caused by disturbances in that air.
- 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 introduced the concept of Nous (Cosmic Mind) as an ordering force, responding to Parmenides on the impossibility of change. He gave scientific accounts of natural phenomena, including a correct explanation for eclipses, describing the Sun as a fiery mass larger than the Peloponnese, and speculating that the Sun might be just another star. He also introduced the notion of panspermia, that life exists throughout the universe. He thought the Earth was flat and floated on strong air, and that disturbances in this air caused earthquakes. He attempted to explain rainbows and meteors. According to Plutarch, Anaxagoras is the first Greek to attempt squaring the circle, a problem he worked on while in prison.
Reader's Guide
Anaxagoras responded to Parmenides by arguing that change is possible because all things are mixtures of primary, imperishable ingredients; no ingredient is ever wholly present or absent, but one becomes dominant. He introduced Nous, or Cosmic Mind, as a pure, independent, and ordering force that set the original homogeneous mixture into motion, separating and arranging like parts. This Mind, possessing all knowledge and power, first manifested as motion and rules all life. Growth and decay are merely new aggregations and disruptions of these parts, and each thing contains heterogeneous elements, its character determined by which homogeneous parts predominate. In astronomy, he correctly explained eclipses, described the Sun as a fiery mass larger than the Peloponnese, and believed the Moon reflected sunlight, had mountains, and was inhabited. He thought the stars were fiery stones of the same nature as the Sun, too distant to give heat, and that the heavenly bodies were masses of stone torn from the Earth and ignited by rapid rotation. He introduced panspermia, the idea that life exists throughout the universe and can be distributed everywhere. He also attempted scientific accounts of rainbows and meteors, and predicted the fall of a meteorite in 467 BC. His theories were based on observations, possibly of the eclipse of 463 BC. He believed the Earth was flat, supported by strong air, with earthquakes caused by disturbances in that air.
Did You Know?
- Anaxagoras deduced a correct explanation for eclipses.
- He described the Sun as a fiery mass larger than the Peloponnese.
- He introduced the concept of Nous (Cosmic Mind) as an ordering force.
- He is the first Greek known to attempt squaring the circle.
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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