Anaximenes of Miletus

Anaximenes of Miletus (c. 586/585 – c. 526/525 BC) was an Ancient Greek, pre-Socratic philosopher from Miletus in Anatolia. He was the last of the three philosophers of the Milesian School, following Thales and Anaximander. These three are considered the first philosophers of the Western world. Little is known of Anaximenes's life and work, as all of his original texts are lost; information is reconstructed from later writers. Anaximenes is known for his belief that air is the *arche*, or the basic element of the universe. He proposed that air could change into other forms through rarefaction or condensation. Condensation would make air denser, turning it into wind, clouds, water, earth, and stone. Rarefaction would make air less dense, eventually becoming fire. He also developed a model of a flat Earth floating on air, with the Sun and stars also floating and revolving around it. Anaximenes is considered one of the earliest figures to develop science, influencing many subsequent Pre-Socratic philosophers and contributing early concepts of natural science, physical change, and scientific writing.