Can abstinence increase the spread of sexually transmitted diseases? Do parents of daughters divorce more often than parents of sons? Do tall people earn more money than shorter competitors, even if they were all the same height in high school?

In Mere sex Is Safer Sex, economist Steven Landsburg brings his witty and razorsharp analysis to the many ways that our individually rational decisions can combine into some truly weird collective result – and he proposes hilarious and serious ways to fix just about everything.