The Greek philosopher Democritus proposed that all matter was made of small, unbreakable particles he called atoms which means unbreakable. He believed that atoms were too small to be seen.
Philosophers are not scientists. They do not test their ideas. Instead they use reasoning to back up their beliefs. To them, human reasoning was superior to experimentation.
460 - 370 BC
Democritus used an example of a beach to support his theory. From afar, the beach appears to be a solid mass.
But up close one finds that a beach is made of small grains of sand too small to be seen from a distance.