The Classical WorldScience & Math Atomism c. 420 BCEMajor Democritus proposes that everything is made of tiny indivisible particles: atoms. ▲ MattersSaveShareTrace roots Longest chain: The Big Bang → First stars ignite → Supernovae seed heavy elements → The Sun forms → Earth forms → First oceans → First life → Photosynthesis evolves → Great Oxidation Event → Complex cells (eukaryotes) → Multicellular life → First animals → Cambrian Explosion → First vertebrates → Jawed fish → Fish walk onto land → The amniotic egg → The Great Dying → Dinosaurs appear → Asteroid ends the dinosaurs → Early primates → Apes split from monkeys → Human line splits from chimpanzees → Walking upright → First stone tools → Genus Homo appears → Homo erectus → Control of fire → Habitual fire and cooking → Homo sapiens appears → Complex language → Natufian villages → Oldest known bread → Agriculture begins → Irrigation → Uruk and the first cities → Cylinder seals → Writing (cuneiform) → Babylonian mathematics → Babylonian astronomical diaries → Thales and natural philosophy → Atomism Community notesLoading notes… Learn more ranked by votesDocumentplato.stanford.eduDemocritus (Stanford Encyclopedia of Philosophy) ↗Editor's pickBookC. C. W. TaylorThe Atomists: Leucippus and Democritus ↗Editor's pickVideoSearch on YouTubeDemocritus atomism explained ↗Editor's pick