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Can you step in to the same river twice?

Can you step into the same river twice? Heraclitus on change an identity.




Heraclitus of Ephesus belongs to the earliest period of ancient Greek philosophy, around 100 years before Plato. He produced beautiful but extremely puzzling writings, provoking human beings to realize how little they understood of really basic ideas such as sameness, difference, and change. Is the constantly changing river that I step into today the same thing it was when I stepped into it before? Am I even the same? How can something be both one way and the opposite way? Heraclitus’ view is quite subtle: it is opposition and change that make everything into a unity. But his ideas greatly influenced Plato, who found his thought challenging. Plato decided that not everything in the world could be changeable, some things must have pure Being, hence his theory of Forms. We shall look at some of the most interesting fragments of Heraclitus’ writings, asking what conceptual framework they reveal, and what influence they had on Plato.

Why is this important?

This is the beginning of philosophy in the Western tradition. The questions posed by Heraclitus and his contemporaries led to the systematic thought of Plato and Aristotle, without which we would have no Western philosophy.


Philosophy, Heraclitus, Plato, change, identity

Year groups

12, 13


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