抄録
We define a kinship-recognizing machine-player (KRP, for short) playing the one-shot Prisoner's Dilemma, which is a generalization of the self-recognizing player discussed by Howard. The KRP can recognize similar opponents as well that are kin to itself, thereby enabling mutual cooperation in a wider class of players. The kinship relation is defined as a computable equivalence relation, describing that two players are kin to each other if they share an ancestor in common. We show the existence of a KRP and the fact that any KRP entails an altruistic player that sacrifices itself to the opponents that are kin to the KRP. It is also discussed that the ability of KRP cannot be extended further to the recognition of all members of any other class of KRP.
