"in his humble opinion": Jim Watson? Humble? There's a first for everything.
Given that WWII showed that race could be dynamite, it's surely astonishing that so many rich countries have permitted mass immigration by people who are not only of different race, but often of different religion. Even more astonishing that they've allowed some groups to keep immigrating even after the early arrivers from those groups have proved to be failures, economically or socially. Did anyone predict that 60 years ago?
"..show students different versions of physics equations that looked plausible, and ask them to figure out which was the correct one": I used to do this. Professor Rosencrantz favours this, I wrote, and Dr Guildernstern that. I stopped when we started getting students who didn't know who R and G were.
Grey, you swine, not gray.