Heraclitus and Parmenides

The Greek Elements (Heraclitus and Parmenides)

Heraclitus of Ephesus focused on fire as the primary substance because he saw change and motion in everything he encountered. Parmenides of Elea, disagreed. He argued that change is impossible, and that all that can occur is the appearance of change. The debate over whether matter is eternal -- unchangeable -- or characterized by constant changes was resolved by a group of philosphers known as the pluralists. This school rejected the philosophies of Thales, Anaximander, and Anaximenes, which assumed that there was a single primary substance, and introduced a model based on the existence of more than one primary substance.