Heraclitus' theory of flux and the metaphor of a flowing river

“Everything flows and nothing stays” and “you can’t step twice in the same river” probably constitute the best known proverbs attributed to the ancient Greek pre-Socratic philosopher Heraclitus of Ephesus (I. c. 500 BCE), regarded as the “father of dialectics” and also called the "weeping philosopher".

As a dialetheist, the hallmarks of his philosophy are the unity of opposites and change, or flux, who, according to Aristotle, he, as a materialist, denies the law of noncontradiction (a law of thought or logical principle which states that something cannot be true and false at the same time). In this sense, when analyzing Aristotle's hylomorphic, scholar W. K. C. Guthrie interprets the distinction between flux and stability as one between matter and form.

Thus, according to W.K.C. Guthrie [Pre-Socratic Philosophy”, Cambridge Encyclopedia of Philosophy (1961) p 443], Heraclitus is a flux theorist because he is a materialist who believes matter always changes while "Plato took flux as the greatest warning against materialism", as said by Zhang, J. [(One and Many: A Comparative Study of Plato’s Philosophy and Daoism Represented by Ge Hong, 2011, Germany: University of Hawaii Press, p. 38].

Furthermore, according to Diogenes La?rtius’ interpretation about Heraclitus's philosophy, "All things come into being by conflict of opposites, and the sum of things flows like a stream."

About that, Classicist Jonathan Barnes ("The Natural Philosophy of Heraclitus", 1982, The Presocratic Philosophers. London & New York: Routledge Taylor & Francis Group. pp. 43–62) states that "Panta rhei, 'everything flows' is probably the most familiar of Heraclitus's sayings, yet few modern scholars think he said it". So, as highlighted by him, notwithstanding the exact phrase was not ascribed to Heraclitus until the 6th century by Simplicius, a similar saying expressing the same idea, panta chorei, or "everything moves" is ascribed to Heraclitus by Plato in the Cratylus.

Since Plato, Heraclitus's theory of flux has been associated with the metaphor of a flowing river, which cannot be stepped into twice.

Thus, according to Barnes, the fragment from Heraclitus's writings has survived in three different forms:

"On those who step into the same rivers, different and different waters flow" — Arius Didymus, quoted in Stobaeus (Eusebius (1903). "Epitomae of Arius Didymus". Praeparatio evangelica. Translated by E.H. Gifford. Clarendon Press. Book XV, Chapter XVIII-XX – via Tertullian Project.)

"We both step and do not step into the same, we both are and are not" — Heraclitus HomerWe both step and do not step into the same, we both are and are not" — Heraclitus Homericus, Homeric Allegories (Heraclitus (commentator). Homeric Allegories)

"It is not possible to step into the same river twice" — Plutarch, On the E at Delphi (Plutarch. On the E at Delphi.)

Anyway, according to Mary Margaret Anne McCabe, professor emeritus of ancient philosophy at King's College London ("Platonic Conversations", Oxford University Press., 2015, pp. 1–31.), the three fragments "could be retained, and arranged in an argumentative sequence", constituting Heraclitus a philosopher capable of sustained argument, rather than just aphorism.

Joshua J. Mark, World History Encyclopedia's co-founder and Content Director, former professor at Marist College (NY), teaches:

“Following in the traditions of the earlier Pre-Socratic philosophers, Heraclitus expounded a physical theory of matter and the physical world much along the lines of Thales, Anaximander and Anaximenes, but took the ideas further in his famous assertion that “Life is Flux” (Panta Rhei in Greek, meaning everything or all things change). If one understands that change is the only constant in life then one will more easily recognize what Heraclitus is saying in his 'obscure' writings when he claims such things as, “The way up and the way down are one and the same. Living and dead, waking and sleeping, young and old, are the same.” These things are the 'same' in that they are all subject to change, arise from one change to vanish into another and all things, constantly, are in flux and are, in that regard, the same.”

“Heraclitus was famous among his contemporaries for his undisguised contempt for all of them and, equally, those who preceded them. Among the over 100 fragments we have of his work is this one which claims: “A knowledge of many things does not teach one to have intelligence; otherwise it would have taught Hesiod and Pythagoras or, again, Xenophanes and Hecataeus. (DK 22B40)”

“Commenting on this, Professor J.M. Robinson explains that Heraclitus is saying how these others wasted their time in speculation on many things - Hesiod with theories on the gods, Pythagoras with a preoccupation of the soul, Xenophanes in asserting there was only one god - while Heraclitus claimed one should focus only on the First Cause which would explain all else: “To know many things - to know the causes of thunder and lightning and earthquakes - is good; but it is better to understand the one thing which underlies all of these - the thought that steers all things through all things. Thisis wisdom. (Robinson, 88)”

“The underlying form of life, the `wisdom' Heraclitus understood, is that the human condition is chiefly characterized by strife, by the coming together and pulling away of opposing forces. While people lament this strife, equating it with suffering, Heraclitus observed that this same process informed the natural world as well writing, "All things come into being through opposition and all are in flux like a river" (DK 22A1). There is no reason, then, to fear or try to avoid strife because conflict is the essential underlying force in life.”

By the way, as a conjunction of the authority of the argument with the argument of authority, I’d like to emphasise Hegel’s prestigious comment about him: "There is no proposition of Heraclitus which I have not adopted in my Logic."

Indeed, as we can infer from Heraclitus’ metaphor, in a few words, life is flux, therefore everything flows, all things change. So, one of the lessons we can learn from the metaphor of the flowing river is that each minute of our lives is a moment, a unique experience, that never comes back, only the memories. Everything passes. Therefore, we should seek to live better, intensely, vibrantly and happily every moment of our lives, if nothing else, so that the memories are as pleasant as possible. As the Romans said: "carpe diem"! In other words, let's seize the day! (Painting by Abraham Janssens, 1601-2)