What “evidence” did democritus use to conclude that atoms exist? since matter is not empty space, it must be made of uncuttable particles (atoms). if you divide up matter into smaller pieces for infinity, you end up with essentially nothing; since matter cannot be made up of nothing, it must have a small fundamental unit of matter that is uncuttable (atoms). the greeks observed that chemical reactions could take place; reactions cannot take place unless matter is made up of uncuttable particles (atoms). democritus did not use any evidence; he simply created the idea of atoms using his imagination. all of these are correct.