Pre-Socratic philosopher

Pre-Socratic philosophy is ancient Greek philosophy before Socrates and schools contemporary to Socrates that were not influenced by him. In Classical antiquity, the Presocratic philosophers were called physiologoi (Greek: φυσιολόγοι; in English, physical or natural philosophers).Aristotle was the first to make a clear distinction between these physiologoi or physikoi ("physicists", after physis, "nature") who sought natural explanations for phenomena, and the earlier theologoi (theologians), or mythologoi (story tellers and bards) who attributed these phenomena to various gods.Diogenes Laërtius divides the physiologoi into two groups: Ionian, led by Anaximander, and the Italiote, led by Pythagoras.

Hermann Diels popularized the term "pre-Socratic" in Die Fragmente der Vorsokratiker (The Fragments of the Pre-Socratics) in 1903. However, the term "pre-Sokratic" [sic] was in use as early as George Grote's Plato and the Other Companions of Sokrates in 1865. Edouard Zeller was also important in dividing thought before and after Socrates. Major analyses of pre-Socratic thought have been made by Gregory Vlastos, Jonathan Barnes, and Friedrich Nietzsche in his Philosophy in the Tragic Age of the Greeks.

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