He travelled extensively, wrote books on every subject, and was considered the equal of the great Plato and Aristotle. But he never founded a school, and so his ideas never had quite the same impact as Plato s and Aristotle s on later civilization. Further, he said that sensations are a matter of atoms falling on the sense organs, and that all the senses are essentially forms of touch. This is called the nomothetic approach, from the Greek work nomos, meaning convention. The soul or mind, he said, is composed of small, smooth, round atoms, a lot like fire or energy atoms, which can be found throughout the bodies of both humans and animals, and even the rest of the world.
Happiness comes from acquiring knowledge and ultimately wisdom.
Sensual pleasure is way too short-lived and fickle to depend on. Democritus did not believe in gods nor an afterlife. He is sometimes called the laughing philosopher, because he found life much more cheerful without what he considered to be these depressing superstitions. It would be many centuries before these ideas would again become well-known. He is the most famous of the group of philosophers known as the sophists.