Democritus of Abdera

Democritus (c. 470-380 B.C.) was an ancient Greek philosopher who pioneered the idea of atoms. He believed that if one broke bits of matter into smaller and smaller pieces, there would eventually come a point where the matter could no longer be divided. This indivisible piece of matter he called an atom. According to Democritus, only atoms and void existed in the universe. He believed that these atoms were eternal, invisible, and everlasting. Also, according to him, atoms had pores, were homogenous, and differed in shape, arrangement, and position. The different shapes accounted for the different states of matter that we have. This matter came from four basic elements: earth, fire, water, and air. These four elements had differently shaped atoms. For example, he believed that water's atoms were smooth and round, and therefore water flowed and had no set form. Fire's atoms were thorny, causing burns, while earth's atoms were rough and jagged which caused them to be moldable and hold their form. He theorized that the number of atoms was constant although the compounds made up of atoms increased and decreased.


Democritus had a very modern idea of how the universe formed. He believed that the original atomic matter was in all directions, and the vibrations of this matter resulted in collisions and whirling movement whereby similar atoms were united to form larger bodies and worlds. This was a result of necessity and not design: normal manifestations of atoms themselves. Atoms are infinite. Motion has always existed. Therefore, infinite worlds composed of similar atoms and motion have always existed.


Interestingly enough, there are no surviving complete texts of the many books that Democritus wrote. Much of his work was lost in the fire of Alexandria. This leaves us with an interesting question with regards to what Democritus actually wrote and how we know what he thought. It is very hard to determine the former, but we can piece together his principles from surviving fragments. The surviving texts are actually citations and paraphrases of Democritus' writings found in the writings of various other ancient authors, such as Heath, Archimedes, Diogenes and Laertius.

Had the work of Democritus not been lost in the fire of Alexandria, history probably would have been different. Granted, not all of his ideas were correct, but had they not been lost we wouldn't have had to rediscover what he had already hypothesized. We could have been much further ahead. Democritus basic principles about atoms were correct in theory, and not until the 20th century did we know that there was something smaller than an atom. Also, if this idea of atoms had been preserved in the writings of Democritus, we probably would have understood the properties of atoms better and earlier. This could have resulted in the use of the atom bomb sooner, or optimistically, we might have even already discovered a way to create fusion and use atomic energy more efficiently and safely. However, it is possible that nothing would have been different. His ideas could have just been ignored until recent times and thus our present day would be nearly the same. Even so, Democritus was ahead of his time, and many years after his death.