Heraclitus of Ephesus

Heraclitus of Ephesus was a Greek philosopher of the late 6th Century BC.

"Both the life and the work of Heraclitus are shadowy, and overlain by later legends and reworkings of his views. The one book he is known to have produced is lost, probably from early antiquity, although he was often quoted and discussed. The guiding idea of his philosophy was that of the logos (law or principle) governing all things: this logos is capable of being heard or hearkened to by people, it unifies opposites, and it is somehow associated with fire, which is preeminent among the four elements that Heraclitus distinguishes: fire, air (breath, the stuff of which souls are composed), earth, and water.

Although he is principally remembered for the doctrine of the 'flux' of all things, and the famous statements that you cannot step into the same river twice, for new waters are ever flowing in upon you, Heraclitus was probably more interested in measured, balanced processes. The more extreme implications of the doctrine of flux (e.g. the impossibility of categorizing things truly) do not seem consistent with his general epistemology and view of meaning, and were left to his follower Cratylus to develop. The primacy of the divine, eternal logos and the contrast between the unstable world of appearance and the order behind it exercised tremendous influence on Plato, and then on the Stoics."