The central analytic tool of classical game theory are solution concepts. They provide a top-down perspective specifying which outcomes of a game are deemed “rational”. This can be given both a prescriptive or a predictive reading. Nash equilibrium is one of the most well-known solution concepts, but we will encounter others below. In the game above, for instance, there are two Nash equilibria in so-called “pure strategies.”[1]  These are the two coordination profiles: \((u, l)\) and \((d, r)\).