Heraclitus
Heraclitus by Johannes Moreelse
Born	c. 535 BC Ephesus, Ionia, Persian Empire
Died	c. 475 BC (age c. 60)
Era	Ancient philosophy
Region	Western philosophy
School	Ionian
Main interests	Metaphysics, epistemology, ethics, politics, cosmology
Notable ideas	Logos, "everything flows", unity of opposites
Influences Anaximander, Pythagoras, Bias of Priene, Zoroaster, Homer
Influenced Parmenides, Plato, Aristotle, Socrates, Stoicism, Hegel, Engels, Nietzsche, Heidegger, Whitehead, Spengler, Popper, McKenna, Pater, D. H. Lawrence

Heraclitus of Ephesus or Herakleitos (c.535 – 475 BC) was a pre-Socratic Greek philosopher. He was a native of Ephesus, Ionia, on the coast of Asia Minor.

His teaching, as we have it now, is a series of epigrams. This means his teachings are sayings and remarks, rather than systematic essays. Heraclitus is famous for his doctrine of change being central to the universe. His famous sayings, "All is flux", and "You cannot step twice into the same river" is still remembered today. Another of his sayings appeals to some psychologists:

• "You cannot discover the depths of the psyche, even if you travelled every road to do so, such is the depth of its meaning".