Greek Philosopher
540-480
Heraclitus of Ephesus is one of the only philosophers who pre-dates Socrates, but still had a profound effect on philsophical thinking. In fact, if we examine Heraclitus's history and works, we can clearly see the impact he had on Socrates and Plato, as well.
Like Socrates after him, Heraclitus attacked contemporary poets and others reputed to be wise because he felt they misrepresented the truth about life. Instead, as his name indicates, Heraclitus's believes that "Everything is in Flux" like the flow of a river. In particular, there are two aspects of reality: the everlasting processes of nature and are own human perspective of the world. Heraclitus challenges people to accept a world which is not made by God, but is "one"; that is to say, the opposites of nature (night/day, living/dying, heating/cooling, etc.) are constantly seeking an equilibirum amongst each other and the unity of the world consists in letting these opposites counterbalance each other.
Additionally, Heraclitus makes sure that his audience is contemplative; he believes that unless people judge their own lives and beliefs, they will never be in tune with the "one" that is life. It is a "fiery" soul that necessitates a man's need to look into his own life, discover the formula of nature, and live appropriately.
As we said earlier, Heraclitus's influence on other philsophers is great, too. The aforementioned "flux" doctrine helped form Plato's cosmology, and the Stoics reference Heraclitus as inspiration for the conception of divine fire. Even the neo-Pyhrronist Aenisedemus gives credit to Heraclitus as a precursor to scepticism.
According to ancient lore, Heraclitus was an arrogant and moody aristocrat. His standing in the ancient Greek community was not that strong because of his political dealings with King Darius of Persia and he was not a proponent of the democratic Greek systems adopted at the time.
Other sources of information
The Window-Heraclitus
Heraclitus: Internet Encyclopedia of Philosophy
Heidegger's Reading of Heraclitus
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