Chemists’ careful advances have helped massively boost lifespans even as our numbers have grownCakeio/Getty“HE MIXES this and that, and he shakes it, and he fiddles around”: Richard Feynman’s description of a chemist in his famous 1959 talk entitled “Plenty of room at the bottom” must have put many noses out of joint. To add to the insult, it’s physicists...