7h 17min, sep 5, 400 y BC - Democritus- A greek philosopher from around 400 B.C. came up with the idea of the atom. He said that if you cut something into smaller and smaller pieces then eventually there would be a piece which was so small it couldn't be cut anymore. He called them “atomos” and said that they were indestructible, have always and will always be in motion, there is empty space between atoms and everything is made of atoms.