Evolutions and Games

Abstract

In Chapter 12 we discussed various solutions for cooperative games. To a large extent, the acceptability of any of these solutions depends on the notion of fairness or equity prevailing in the society (the group of players). People differ in their perception of ‘fairness’. Consequently, there has been an ever-increasing number of solution concepts in cooperative game theory without any ‘clear criterion as to which solution concept is to be employed in analyzing any real-life social situation’ (Harsanyi and Selten, 1988). On the other hand, refinements of Nash equilibrium are based on various notions of rationality. This is also not a very satisfactory way of explaining how games are played by the players in real life situations (see the introductory comments by Binmore in Weibull, 1995). An alternative approach to the resolution of games appeared in Maynard Smith (1982) which made an enormous impact on the literature in game theory. This approach originated from the observation of evolutionary process in animal kingdom (Maynard Smith and Price, 1973). At any point of time, each group of animals in an animal society has a given history of behaviour. Each animal faces the following problem: should I behave in the way which my history (or tradition) dictates or should I adopt the behaviour of some other group? Each animal in this polymorphic society is trying to select the best behaviour. The emphasis in evolutionary games is not optimization but stability of behaviour.