"In any case, the number three fitted perfectly the way quarks occur in nature." -Murray Gell-Mann You might think that we know it all, at least as far as knowing-it-all is possible. After all, we know that matter is made up of atoms, which are made up of electrons and nuclei, and the nuclei are made up of protons and neutrons, and then the protons and neutrons are made up of quarks and gluons.