Democritus developed atomism into a wide-ranging account of nature, perception, knowledge, and ethical cheerfulness grounded in atoms moving through void.
Intellectual setting
Democritus answered Eleatic restrictions on change with a pluralist physical theory and participated in broader fifth-century debates about sensation and knowledge.
Key ideas
Conventional qualities
Sensible qualities depend on the observer and arrangement, while atoms and void underwrite the causal account.
Euthymia
Ethical fragments value a balanced, steady state of mind achieved through moderation and practical judgment.
Legacy
His atomism became the principal ancient materialist alternative inherited by Epicurus and Lucretius.