Anaximander of Miletus

Influenced: All pre-socratic philosophy, in particular, Anaximenes, Pythagoras, Democritus and Greek astronomy

Influenced by Thales of Miletus

Anaximander (c. 610 – c. 546 BC, ~64 years old, lived during the Archaic period (c. 750 – c. 500 BC)) was a pre-Socratic Greek philosopher who lived in Miletus, Ionia in Asia Minor (modern west coast turkey). He belonged to the Milesian school and learned the teachings of his master Thales.

• Father of Cosmology
• Made three important astronomical speculations: 
  • (1) that the celestial bodies make full circles and pass also beneath the earth
  • (2) that the earth floats free and unsupported in space
  • (3) that the celestial bodies lie behind one another and thought them as hollow concentic wheels
• First to write down his philosophy, earliest written in prose at least in the Western world
• Some consider him evolution's most ancient proponent
• First to create the map of the world, his innovation was to represent the entire inhabited land known to the ancient Greeks
• Introduced the gnomon to Greece from the Babylonians.
• First to employ, in a philosophical context, the term archế, the first principle, from which everything we perceive is derived. So he asked the question what is the cause of all things?
• For Anaximander this was the Apeiron (“that which has no boundaries”), an endless, unlimited primordial mass, eternal and infinite, subject to neither old age nor decay, from which all things are born and to which all things will return
• First to conceive a mechanical model of the world and the cosmos
• First to realize the obliquity (or the Earth's axial tilt)
• First known example of using an argument that is based on the principle of sufficient reason