In fact marriage – monogamous marriage – did change everything. Far from being an instrument of oppression, the development of monogamy was one of the great civilizing influences of Western history. The spread of monogamous marriage reduced the male-male competition over women by ensuring that (in theory, at least) there’s a woman for every man. This shrinks the pool of low-status, risk-oriented, desperate, unmarried men – the ones who are responsible for nearly all the crimes. Fewer unmarried men means a sharp decline in rape, kidnapping, murder, assault, robbery and other social disorders. Monogamous marriage makes the world more civilized. This is what Joseph Henrich, a professor of human evolutionary biology who’s now at Harvard, argues.
