Sweet exists by convention, bitter by convention, color by convention; but in reality atoms and the void alone exist
DemocritusDo not trust all men, but trust men of worth; the former course is silly, the latter a mark of prudence.
DemocritusBy convention sweet is sweet, by convention bitter is bitter, by convention hot is hot, by convention cold is cold, by convention color is color. But in reality there are atoms and the void. That is, the objects of sense are supposed to be real and it is customary to regard them as such, but in truth they are not. Only the atoms and the void are real.
Democritus