Isn't there a game theory example that is basically a variation of the game these guys used to demonstrate their theory. I'm thinking of the game where you have 2 players who can do 1 of 3 things when it is their turn. They can either hurt the other guy, or do nothing to the other guy, or help the other guy. Game theory says that to get the other guy to help you, you should mimic what he does. So if he hurts you, during your next turn you hurt him. Then if he does nothing, you do nothing. Eventually, if the other guy is rational, he will figure out that if he helps you everytime, you will help him everytime in return.