“We both step and do not step into the same, we both are and are not”

— Heraclitus

Heraclitus’ philosophy was concerned with change. None of Heraclitus’ writings survive in their original form, only in fragments repeated by others. This fragment comes from Heraclitus’ only known work, “On Nature”:

“We both step and do not step into the same, we both are and are not”

— Heraclitus Homericus, Homeric Allegories

There are two more fragments of a similar nature that are either different intepretations of the same concept or continuations of the same work:

“It is not possible to step into the same river twice”

— Plutarch, On the E at Delphi

“On those who step into the same rivers, different and different waters flow”

— Arius Didymus, quoted in Stobaeus

Heraclitus saw the world as constant change; always becoming, but never being. A river serves as his metaphor because a river is by definition never the same as it was a moment ago. Just as a river must be in constant change to exist, so too do we. We exist as a product of constant change; never the same from one moment to the next.

“The hardest stone, in the light of what we have learned from chemisty, from physics, from mineralogy, from geology, from psychology, is in reality a complex vibration of quantum fields, a momentary interaction of forces, a process that for a brief moment manages to keep its shape, to hold itself in equilibrium before disintegrating again into dust
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