Anaximenes
Everything is made of air: thinned out it becomes fire, pressed together it becomes wind, water, earth and stone.
Placement
Third of the Milesian natural philosophers, associate of Anaximander: everything is air, which becomes fire when rarefied and wind, cloud, water, earth and stone when condensed.
Key ideas
- Air as the primary substance (arché)
- Rarefaction and condensation
- The earth riding flat on air
Teachers: Anaximander
Influence
Influenced by 1
Anaximander studied with
studied with later tradition ✓
Known only from later tradition (Diogenes Laertius 2.3; Theophrastus, as preserved by Simplicius, In Physica 24.26, calls him only a ‘companion’); the succession may be a later construction. Diogenes Laertius 2.3; Simplicius, In Physica 24.26 Diels (DK 13 A5, after Theophrastus)
Evidence: also in Wikidata · Wikidata
Anaximander › c. 610–546 BCE
Influenced 1
Anaxagoras
influenced disputed
Anaxagoras kept Anaximenes’ flat earth riding on air; the ancient tradition that makes him Anaximenes’ pupil is chronologically doubtful. Aristotle, De caelo II.13, 294b13–21; Diogenes Laertius II.6; SEP “Anaxagoras”
Evidence: AI draft
Anaxagoras › c. 500–428 BCE
Position
Like Anaximander, Anaximenes looked for one source of all things, but he chose something definite rather than the boundless: air (aēr), which he took to be infinite in extent, always in motion and the stuff of life and soul. What made the choice powerful was the mechanism. Air rarefied becomes fire; condensed it becomes wind, then cloud, water, earth and finally stone. Differences in quality thus come from differences in density, a single process that runs in both directions. He pointed to everyday experience: breath blown through pressed lips feels cold, breath from an open mouth feels warm. His cosmology had the earth flat and riding on air like a leaf, with the heavenly bodies also flat and turning around the earth. The report that he compared the soul holding us together to air holding together the cosmos may preserve his own words, though scholars disagree. Later thinkers took up his scheme: Anaxagoras kept the flat earth supported by air, and in the fifth century Diogenes of Apollonia made air the principle of a whole natural philosophy.
Life & context
Anaximenes, son of Eurystratus, lived in Miletus in the sixth century BCE; his exact dates are uncertain. Theophrastus called him an associate of Anaximander, and later tradition made him Anaximander’s pupil, which makes him the third of the Milesian natural philosophers after Thales. According to Diogenes Laertius he wrote a book “in simple and unaffected Ionic”. Nothing of it survives except perhaps a single sentence; his views are known from Aristotle, Theophrastus and later reports in Simplicius, Hippolytus and Aetius.
Main works
- On Nature (6th century BCE, lost; one possible fragment)
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