Presocratic Philosophers were the first Greek philosophers of the Western tradition. Some of this philosophers were the Milesian Thales of Miletus, Anaximander of Miletus and Anaximenes of Miletus, Xenophanes of Colophon and Heraclitus of Ephesus, Parmenides of Elea, his pupil Zeno of Elea, Pythagoras of Samos, the Eliastics Melissus, the Pluralists Anaxagoras of Clazomenae and Empedocles of Acragas, the Atomists Leucippus and Democritus of Abdera and the Sophists Diogenes of Apollonia. Aristotle refers to them as Investigators of Nature because of their interest on questions of physics (as the material principle).
- Presocratic interests extended to religious and ethical thought, the nature of understanding, mathematics, meteorology, the nature of explanation, and the roles of mechanism, matter, form, and structure in the world. Almost all the Presocratics seemed to have something to say about embryology, and fragments of Diogenes and Empedocles show a keen interest in the structures of the body; the overlap between ancient philosophy and ancient medicine is of growing interest to scholars of early Greek thought 
It was Pythagoras (ca. 582 - 504 BC) who first brought Philosophy into connection with practical life; he also gave Philosophy its name "the love of wisdom".