You Cannot Step into the Same River Twice

As strange as it may sound, taking each word of this phrase literally leads us to the conclusion that a person cannot step into the same river twice. With each subsequent step, both the person and the waters of the river will have changed.

With this simple observation and the famous phrase
"Everything flows" (‘Τα πάντα ρει’) (a phrase that was actually not written by him, but by Plato referring to him), the pre-Socratic philosopher Heraclitus formulated the law of perpetual motion, highlighting change as the most significant characteristic of nature.

Everything operates in motion, and every moment is unique in an absolute sense. Everything in nature exists in conflict, which is essential for life and evolution. This flow creates and destroys everything in an endless yet harmonious struggle of opposing forces.

Evil is as necessary as good. The beginning and the end in a circle are the same. The descent and ascent are the same path from a different perspective. Fullness follows hunger, rest follows fatigue, health follows sickness, day follows night, war follows peace. Without this relentless play between opposites, the world would cease to exist.

While inertia seeks permanence and stability, in all the changes, transformations, and oppositions, Heraclitus saw unity and completion. 

This conception of the interdependence of opposites and the transcendence of illusory dilemmas is his most important legacy. The next time you step into a river, hold on to the memory of the water and of yourself. Bring it back to mind the next time you step into the 'same' waters. Perhaps you won't notice the change in the river—no matter how much you theoretically understand that it exists. Instead, look more closely for the change within yourself.