How to Encourage

Cooperation

Political Scientist Robert Axelrod

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

TIT FOR TAT

1st encounter with any program, Tit for Tat cooperates

2d encounter: Tit for Tat did what the other program did on previous encounter

Tit for Tat never gets repeatedly

victimized &never gets locked into

mutually costly chains

of mutual betrayal

Simple conditional cooperation is more infectious than unmitigated meanness

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

Most of Tit for Tat’s neighbors were designed to cooperate under at least

some circumstances

We are designed to cooperate under at least some circumstances

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.

How Do You Play Tit for Tat?

Cooperate Retaliate for Betrayal

Forgive Return to Cooperation