What Kepler needed, Alex Bellos writes, was an optimal strategy — a way, not to guarantee success, but to maximize the likelihood of satisfaction. And, as it turns out, mathematicians think they have such a formula.

It works any time you have a list of potential wives, husbands, prom dates, job applicants, garage mechanics. The rules are simple: You start with a situation where you have fixed number of options (if, say you live in a small town and there aren’t unlimited men to date, garages to go to), so you make a list — that’s your final list — and you interview each candidate one-by-one. Again, what I’m about to describe doesn’t always produce a happy result, but it does so more often than would occur randomly. For mathematicians, that’s enough.

They even have a name for it. In the 1960s it was called (a la Kepler) “The Marriage Problem.” Later, it was dubbed “The Secretary Problem.”