Democritus in 5th century B.C. Greece was walking along the beach with his teacher and asked the question “Is the water in the ocean continuous or is it made up of tiny uncuttable particles (atomos)?” Leucippus, his teacher, probably turned the question back to Democritus, who answered “I believe that water is made of very tiny particles.” This is how the idea of atoms was born. For the next 2,000 years, the idea of atoms was held by few scientists or natural philosophers.