Heraclitus of Ephesus was a pre-Socratic philosopher from Ionian Ephesus. Heraclitus claimed an insight into the world order different from all conventional ways of conceiving. Hence his sustained critique of most people's superficial perception of reality and way of life.

A recurring theme of his philosophizing is the natural process of constant becoming and change. In later times this change was brought on the popular short formula panta rhei ("everything flows"). Furthermore, Heraclitus dealt with the relationship of opposites, such as day and night, waking and sleeping, concord and discord. He saw these opposites standing in a tension-laden unity.


Heraclitus of Ephesus (c. 535–c. 475 BCE) was a pre-Socratic Greek philosopher known for his profound and enigmatic insights into the nature of reality. Little is known about his life, but his philosophical fragments reveal his unique perspective.

Heraclitus believed that change and flux were fundamental aspects of the universe. He famously stated that "everything flows" or "you cannot step into the same river twice," highlighting the impermanence and constant transformation of the world.

He emphasized the concept of "logos," often translated as "word" or "reason," as an underlying principle that governs the universe. Heraclitus saw the world as a harmony of opposing forces, with strife and conflict playing a role in maintaining balance.

His ideas about change and unity influenced later philosophers, including Plato and Aristotle. Heraclitus' philosophy laid the groundwork for discussions about the nature of existence, the interplay of opposites, and the interconnectedness of all things. Despite his limited surviving works, his insights have had a lasting impact on the development of Western thought.

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