Full Idea
Prisoners A and B can support or betray one another. If both support, they each get 1 year in prison. If one betrays, the betrayer gets 0 and the betrayed gets 3. If they both betray they get 2 each. The common good is to support each other.
Gist of Idea
Two prisoners get the best result by being loyal, not by selfish betrayal
Source
William Poundstone (Prisoner's Dilemma [1992], 06 'Tucker's')
Book Reference
Poundstone,William: 'Prisoner's Dilemma' [OUP 1992], p.118
A Reaction
[by Albert Tucker, highly compressed] The classic Prisoner's Dilemma. It is artificial, but demonstrates that selfish behaviour gets a bad result (total of four years imprisonment), but the common good gets only two years. Every child should study this!