The document discusses how the computer program "Tit for Tat" was able to prevail in a game theory experiment by cooperating on the first encounter and then doing whatever the other program did on the previous encounter. This simple conditional cooperation strategy proved more effective than consistent meanness. The document also notes that brain imaging studies have shown cooperation activates reward centers in the brain similar to drugs or good fortune.

1. How to Encourage Cooperation

2. Political Scientist Robert Axelrod

3. asked game theory experts to submit computer programs designed to prevail in game providing rewards either for refusing to cooperate or for cooperating when the programs encountered other programs

5. TIT FOR TAT

6. 1 st encounter with any program, Tit for Tat cooperates 2d encounter: Tit for Tat did what the other program did on previous encounter

7. Tit for Tat never gets repeatedly victimized & never gets locked into mutually costly chains of mutual betrayal

8. Simple conditional cooperation is more infectious than unmitigated meanness

9. if tit for tat had been tossed into the game with 49 steadfast non-cooperators, there would have been a 49-way tie for first place Robert Wright, The Moral Animal

10. Most of Tit for Tat’s neighbors were designed to cooperate under at least some circumstances

11. We are designed to cooperate under at least some circumstances

12. When volunteers playing the Prisoner’s Dilemma Game cooperated with one another, the “reward circuits” of their brains were activated, the same regions that are activated when certain drugs are taken or when good fortune befalls us Emory University Professor Gregory Berns .

13. How Do You Play Tit for Tat? Cooperate Retaliate for Betrayal Forgive Return to Cooperation