What are the similarities and differences between Heraclitus and Parmenides?

  Parmenides took the view that nothing changes in reality; only our senses convey the appearance of change. Heraclitus, by contrast, thought that everything changes all the time, and that "we step and do not step into the same river," for new waters flow ever about us.

  Heraclitus and Parmenides were two of the most influential and enigmatic of the Presocratic philosophers. Heraclitus argued for the idea that reality is impermanent, while Parmenides argued that reality is static.

new evidence is discovered.

oversights and errors are corrected,

new technology is applied to evidence.