Miletus

Anaximander A fellow citizen and disciple of Thales of Miletus, Anaximander (c. 610–546 BCE) was one of the boldest minds of the Milesian school and perhaps the first thinker to write a prose treatise on nature. Tradition credits him with the pioneering use of the term arché (“principle”), as well as remarkable achievements: drawing the first map of the inhabited world and introducing the gnomon (sundial) into Greece. Dissatisfied with Thales’s water, Anaximander proposed as the principle the apeiron — the boundless, indeterminate, and imperishable. No particular element could give rise to all the others without being consumed by them; only something indefinite and inexhaustible could be the eternal source of everything. From the apeiron, eternal and divine, the opposites (hot and cold, wet and dry) separate out, and from this separation worlds are born — which, in due time, return to it. The only surviving verbatim fragment, transmitted by Simplicius, speaks of this cosmology in moral terms: things “pay one another penalty and retribution for their injustice, according to the order of time.” ...

Anaxímenes The third great name of the Milesian school, Anaximenes (c. 585–525 BCE) was a disciple of Anaximander. At first glance he took a step back, rejecting his master’s indeterminate apeiron and returning to a concrete element as the principle: air (aēr). But his choice carried a decisive advantage — air, being determinate, allowed him to explain how the single principle transforms into all things, something that neither Thales’s water nor the apeiron explained clearly. ...

Thales of Miletus A philosopher from Miletus, in Ionia (in present-day Turkey), who lived around 624–546 BCE, Thales is considered the first philosopher of the Western tradition and was counted among the legendary Seven Sages of Greece. He left no writings; what we know comes from later reports, above all from Aristotle, who hailed him as the founder of this kind of inquiry (Metaphysics I, 3). Many stories gathered around his name: he is said to have predicted a solar eclipse, measured the height of the pyramids by their shadow, and, according to Aristotle, demonstrated the practical value of philosophy by foreseeing a good harvest and cornering the olive-press market. ...