Re: Prisoner's Delemma

Kennita Watson (
Tue, 1 Jul 1997 03:20:10 -0400 (EDT)

John K Clark (
>If everybody adopted a tit-for-tat strategy most people and the world in
>general would be better off, however a mutant that always defected would do
>better than anybody else in such a population. A defector would produce more
>descendants, until a sizable fraction of the population were defectors, and
>then they would be worse off than their honest contemporaries and their
>numbers decline.

In a population of 10 people, if 9 play tit-for-tat and one always defects,
the 9 will be defected against 10% of the time, and the one will be defected
against 100% of the time. This isn't useful for producing descendants.

The reason you don't see 100% honest people is that a) most people don't
consistently play tit-for-tat, and b) hardly anybody _always_ defects
("honor among thieves" and all).


Kennita Watson | The bond that links your true family is not one of blood,| but of respect and joy in each other's life. Rarely do
| members of the same family grow up under the same roof.
| -- Richard Bach, _Illusions_