While Democritus didn't have the scientific tools to prove his idea, he proposed that matter was made up of indivisible particles called atoms. He believed that atoms were solid, homogeneous, and eternal, and that all matter was made up of different combinations of these atoms.
It's important to note that Democritus' concept of the atom was purely philosophical and not based on scientific evidence. It wasn't until much later, in the 19th century, that scientists like John Dalton were able to develop the atomic theory that we know today.
