Fortunately, we now know the truth. At last we have been vouchsafed clear insight into the laws of life. We now know that men are not, and never will be, equal. We know that environment and education can develop only what heredity brings. We know that the acquirements of individuals are either not inherited at all or are inherited in so slight a degree as to make no perceptible difference from generation to generation. In other words: we now know that heredity is paramount in human evolution, all other things being secondary factors.

Lothrop Stoddard, 1920