Theoretical Background:

The simulators on this site are based for the most part on "game theory". Game theory is originally an area of economics devoted to the analysis of the strategic interaction of rational agents. It has since been extended to apply to the proliferation of strategies in populations of biological agents where strategies breed true, and in cultural dynamics where strategies are imitated on the basis of perceived success. A large part of the extant literature concerns the conditions under which cooperative behavior stabilizes, as do the simulators in this site.

A game is an interactive situation characterized in terms of payoffs. The most common cases are those where two players can each make two moves, and how well each one does depends on which move both players make. There are thus four possible outcomes, and the "payoff matrix" specifies payoffs for both players in all four situations. For instance, the following matrix gives the familiar "prisoner's dilemma" payoffs.

The first number is Player 1's payoff in the situation, the second is Player 2's.  Game theorists have a variety of tools that allow them to say something about how rational agents will choose to play when they know they are playing against other rational agents. For instance in the "prisoner's dilemma" (above) rational agents will choose to defect, even though it is clear that they could do better by both cooperating.

Evolutionary game theory wonders about how inherited (or imitated) strategies evolve. One can analyze the same "games" that game theorists analyze in the context of evolutionary processes, both biological and cultural. Sometimes evolution and rational choice give the same outcome (in terms of which behavior stabilizes), sometimes they don't.

You will find bits of information on game theory throughout the site, as it pertains to the particular simulators. If, however, you would prefer a more systematic introduction, the following links are recommended.  

• Stanford Encyclopedia of Philosophy: Game Theory
• Stanford Encyclopedia of Philosophy: Prisoner's Dilemma
• What is Game Theory?
• Pricipia Cybernetica: Game theory
• Paul Walker's History of Game Theory

[Other suggestions?  mailto:bharms@interchange.ubc.ca]