Through my readings of Plato I've become aware of his antedecents and presocratic inspirations. The annotations to Republic makes it clear that Plato integrated the views of two important presocratics that are often put in opposition, Heraclitus and Parmenides.

Heraclitus held that everything changes and nothing is stable. Becoming as a concept is assigned to him, famously he is quoted as no man ever steps into the same river twice. The waters of the river are ever changing, so is the man. Yet in the change there is still unity, which is also seen in fire which has nothing to grasp yet still remains a "thing".

Parmenides held that multiplicity was an illusion, that the world is one unity that is uniform, indivisble and unchanging. Being is ascribed as championed by Parmenides.

Both hold the universe to be a unity, but differ on becoming and being.

The philosophy outlined by Plato in Republic is seen as a synthesis of these opposing worldviews. The realm of forms is being, while the world of the unreliable senses represents becoming. By reading the collected testimonies and fragments of these presocratic philosophers I hope to gain greater understanding of those that came afterwards.