There is something else, and more important, that distinguishes the Atomists from their contemporary philosophers. Their approach anticipated much of what we now know about science and knowledge. They were content with describing mechanical processes, instead of pursuing teleological dead-ends.
Bertrand Russell writes:
"[...] experience has shown that the mechanistic question leads to scientific knowledge, while the teleological question does not. The atomists asked the mechanistic question, and gave a mechanistic answer. Their successors, until the Renaissance, were more interested in the teleological question, and thus led science up a blind alley."
The curse of teleology is not confined to the natural sciences. In the social sciences, the undying quest for a desired result, without a full understanding of the processes and structures involved, has led to much disaster.
I named my blog after the Atomists, partly in honor of these insights -- and also because the mirthful Democritus was known as the laughing philosopher.