That's a really bizarre post. He writes about game theory as if he doesn't want to assume much knowledge, but then he throws out "copula" as if he assumes it will be familiar. I can't figure out who he's writing for. And I have no idea what's up with "For example, there are two equilibrium outcomes in a game of Chicken, but that doesn't mean that each equilibrium is equally likely. It means that the entire concept of likelihood or probability functions has no meaning here". There are three equilibrium for Chicken, the third being a mixed strategy that decides whether to swerve or not with equal probabilities. I guess he could be talking about only pure strategies, but then I have no idea what he could be getting at with "that doesn't mean that each equilibrium is equally likely."