A famous quote from Carl Sagan in the marvelous Cosmos documentary where he explains atoms by slicing an apple pie until you can not slice no more because you are down to a single elementairy particle the atom.

Carl also references Plato's Republic when visiting the actual cave where Plato lived.

Carl also references books classical mechanics but not the book the parent comment mentions but earlier ones like Al-Baghdadi, Cristian Huygens, Galileo, Newton.