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Did the Greeks discover atoms?

People ask us questions and we try to answer them.
July 5, 2017

The concept of atoms is quite old. Proof of their existence required modern science.

Democritus (see images above) lived about two hundred years before Aristotle and Plato, and is often credited with originating the concepts of the atom. He was a philosopher, and his idea was to try to explain why different materials had different properties, such as why are liquids flexible and solids less flexible. We know now that the atoms, for example in ice, water, and steam are all made of the same kinds of atoms. Many Greeks of the time thought that the highest form of research was thinking about things, because the mind and ideas are superior to the world and the senses, or something like that. The word “atom” means indivisible, and in that sense, the Greeks were sort of correct. I would argue they really had no idea what atoms really are.

John Dalton, in the early 1800s, more than 2,000 years after Aristotle, formulated the first modern version of atomic theory, and by then he had enough scientific data to actually do a pretty good job of describing an atom, as we now understand it. Still, there was no direct evidence to prove the existence of atoms, and Dalton’s atomic model was primitive by modern standards.

It wasn’t until 1905 that Albert Einstein published a paper that actually proved the atomic theory, and ever since then, the model of the atom has been corrected and improved many times.

Gordon McDonough, Science evangelist