Heraclitus: Pre-Socratic Philosopher of Flux

Pre-Socratic Philosopher of Flux

Utrecht Moreelse Heraclitus
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Heraclitus of Ephesus (fl. 500 B.C.) was a pre-Socratic Greek philosopher, known for an expression commonly paraphrased as "you can't step twice in the same river." The IEP lists the actual (translated) quote as:

"On those stepping into rivers staying the same other and other waters flow."

Heraclitus is also known for espousing the theory of universal flux, or "the coincidence of opposites," and the centrality of fire.

Diogenes Laertius says that Heraclitus won the honorary title of king of the Ionians and wrote a book that he deposited at the temple of Artemis at Ephesus. (Over 100 fragments survive.) The book was divided into separate sections on cosmology, politics, and theology.

Heraclitus is not connected with one of the other Pre-Socratic schools. He believed that everything is fire in some modified form. He also believed that everything is always changing or in a constant state of flux, and this "entails the coincidence of opposites," meaning that things are both the same and opposite of each other at the same time.

Heraclitus is the first known to use the word kosmos for world order, which he says ever was and ever will be, not created by god or man.

Heraclitus is called a monist (because he believes fire is the underlying principle) and an elitist (he believes most people are stupid). Although Heraclitus does not seem to have been in a school, he may have influenced Parmenides, Empedocles, Democritus, Plato, and the Stoics.


Little is known about Heraclitus’ life, as the one book he apparently wrote has been lost. Heraclitus was unpopular in his time, according to the Encyclopedia Britannica:

“Heraclitus was unpopular in his time and was frequently scorned by later biographers. His primary contribution lies in his apprehension of the formal unity of the world of experience.

Though he was primarily concerned with explanations of the world around him, Heraclitus also stressed the need for people to live together in social harmony. He complained that most people failed to comprehend the  logos (Greek: “reason”), the universal principle through which all things are interrelated and all natural events occur, and thus lived like dreamers with a false view of the world.”

Examples:Heraclitus was an Ephesian nobleman with contempt for the masses. He wrote "On Nature" in the Ionic dialect in prose that was difficult enough for his contemporaries to award him the epithet "the obscure." J. V. Luce, in An Introduction to Greek Philosophy, says the paradox that encompasses all of Heraclitus' work is "the Identity of Opposites." Dark cannot exist without Light, Cold without Hot, Death without Life, etc. Heraclitus also says that the kosmos is now, was, and ever will be and that no god ever created it.