(or in economics or other realms of life). Others insist that game theory does not predict, but prescribes—it tells you what you ought to do (if you want to win the game), not what any player would actually do in a game. Or some experts will say that game theory predicts what a “rational” person will do, acknowledging that there’s no accounting for how irrational some people (even those playing high-stakes games) can be. Of course, if you ask such experts to define “rational,” they’re likely to say that it means behaving in the way that game theory predicts.
To me, it seems obvious that basic game theory does not always successfully predict what people will do, since most people are about as rational as pi. Neither is it obvious that game theory offers a foolproof way to determine what is the rational thing to do. There may always be additional considerations in making a “rational” choice that have not been included in game theory’s mathematical framework.
Game theory does predict outcomes for different strategies in different situations, though. In principle you could use game theory to analyze lots of ordinary games, like checkers, as well as many problems in the real world where the concept of game is much broader. It can range from trying to beat another car into a parking place to global thermonuclear war. The idea is that when faced with deciding what to do in some strategic interaction, the math can tell you which move is most likely to be successful. So if you know what you want to achieve, game theory can help you—if your circumstances lend themselves to game theory representation.
The question is, are there ever any such circumstances? Early euphoria about game theory’s potential to illuminate social issues soon dissipated, as a famous game theory text noted in 1957. “Initially there was a naive band-wagon feeling that game theory solved innumerable problems of sociology and economics, or that, at the least, it made their solution a practical matter of a few years’ work. This has not turned out to be the case.”23
Such an early pessimistic assessment isn’t so surprising. There’s always a lack of patience in the scientific world; many people want new ideas to pay off quickly, even when more rational observers