I think most people would accept that a majority of people blindly follow rules and accept toxic nonsense (your 2/3rds) while a smaller, but still substantial portion (roughly 1/3?) do what's in the best interest of themselves and the world they live in.
This is so self-evident that I don't think it needs a theory. Those who want this to be a theory are by its own definition "level 3" or something :^)