Human males have never been thought of as models of sexual restraint — and with good reason. From the moment the adolescent libido begins to boot up, boys seem to enter an ongoing state of emotional — if not literal — priapism, from which they never fully emerge. As far as nature is concerned, this is just fine. The goal of any organism, after all, is to ensure the survival and propagation of its genes, and males — far more so than females — are eminently equipped to do that. Even the world’s most reproductively prolific mothers rarely produce more than eight or nine children in a lifetime. Males can conceive everyday, even multiple times a day, and come emotionally hardwired to do just that. Part of the reason they don’t, apart from the impracticality of trying to raise a brood of 200 children, is that they just don’t get that many mating opportunities. Sex requires a willing partner, and females, with so much more on the line in terms of the time, effort and energy that pregnancy and child-rearing involve, can be extremely selective in choosing mates. That requires males to develop a whole suite of emotional muscles — self-denial, self-restraint, a facility for delayed gratification — that will help them cope with an appetite that at some levels will never be fully satisfied. And that, in turn, is a central pillar of monogamy and fidelity. (More on TIME.com: Sex and Politics: Are Powerful Men Really More Likely to Cheat?) But what happens when the lid comes off? What happens when the opportunities are unlimited? In some cases, not much. Males either continue to practice self-control or, after a brief period of happy debauchery — think rock stars or leading men who are always seen stepping out with a new piece of arm candy —  finally settle down into stable monogamy. In some cases, though, the stability never happens; in some cases, unlimited opportunity simply leads to unlimited appetites. Emperors and despots may be best known for this kind … Continue reading The Caligula Effect: Why Powerful Men Compulsively Cheat