It is impossible in the end to deny that even a highly conditioned trait can be without some basis in biology—or vice versa. Nurture always reinforces nature; it rarely fights it. (An exception may be aggressiveness, which develops more in boys despite frequent parental discouragement.) I find it very hard to believe that the fact that 83 percent of murderers and 93 percent of drunken drivers in America are male is due to social conditioning alone.
