To Play Prisoner's Dilemma Effectively Deploy Gandhian TIT FOR TAT

The Economist September 29, 2007 says: “A version of the “prisoner's dilemma” may suggest ways to break through the Kyoto impasse.”

What is Prisoner's Dilemma?

“In it, two prisoners accused of the same crime find themselves in separate cells, unable to communicate. Their jailers try to persuade them to implicate one another. If neither goes along with the guards, they will both receive a sentence of just one year. If one accepts the deal and the other keeps quiet, then the turncoat goes free while the patsy gets ten years. And if they both denounce one another, they both get five years.

If the first prisoner is planning to keep quiet, then the second has an incentive to denounce him, and so get off scot-free rather than spend a year in prison. If the first prisoner were planning to betray the second, then the second would still be better off pointing the finger, and so receive a five-year sentence instead of a ten-year one. In other words, a rational, self-interested person would always betray his fellow prisoner. Yet that leaves them both mouldering in jail for five years, when they could have cut their sentences to a year if they had both kept quiet.

Pessimistic souls assume that the international response to climate change will go the way of the prisoner's dilemma. Rational leaders will always neglect the problem, on the grounds that others will either solve it, allowing their country to become a free-rider, or let it fester, making it a doomed cause anyway. So the world is condemned to a slow roasting, even though global warming could be averted if everyone co-operated…”.

I first read about Prisoner's Dilemma in the essay by Douglas R. Hofstadter (now part of his book “Metamagical Themas, Penguin 1985) for Scientific American (May 1983).

It was an eye opener. I learnt you don’t have to be clever and cunning to be effective

A menacing sounding but actually very simple strategy, translated in a computer program called “TIT FOR TAT”, wins against very complex and cunning strategies.

TIT FOR TAT uses a very simple tactic:
Cooperate on move 1;
thereafter , do whatever the other player did the previous move

Today we are talking of Prisoner's Dilemma for climate change, yesterday it was about cold war and nuclear weapons, tomorrow it will about something else.

For the complex global issues and our every day mundane ones let us never forget elegant and effective TIT FOR TAT.

Let us not waste our time like the “clever prisoners” are doing in Alan Dunn's picture below.


Artist: Alan Dunn The New Yorker 6 Nov 1948