If all the men will only settle for the best-looking woman—and vice versa—almost everybody is going to end up unhappy. In 1962 two mathematicians worked out how, given a little compromise from everyone, you could actually make everyone happy. David Gale and Lloyd Shapley showed that if everyone compiles a ranking, in order of desirability, of potential partners, it is possible to arrange things into a stable equilibrium state. In this equilibrium, people are partnered in such a way that it is impossible to find a man and a woman from different couples who would both rather be married to each
...more
