Roger Penrose is the Rouse Ball Professor of Mathematics at the University of Oxford. E.g. he’s the inventor of Penrose Tiles, which can cover a plane but only aperiodically (nice effect!). And he has proved, rigorously!, that you are smarter than him. Or, to be ultra-precise, he has proved that there are Mathematical Truths™ that you can easily see but he cannot. In this posting I shamelessly reproduce his proof.