>>519222415
If people could be rational it is an obvious problem. If you even mix in a small amount of retards then your population will become more retarded and your population as a whole will be weakened in future generations. Now imagine if you mix in 150 million retards that are all retarded in different ways, now your population is fucked, and any hope of them rising up to level of your forefathers is impossible, because now the next generation is a more primative and underevolved people than the ones that came before them. Even a little bit of contamination matters, and we are already majorly contaminated.