Locus of control and strategic behaviour in a prisoner's dilemma game

Previous research reported inconclusive and even contradictory findings on the relationship between locus of control and cooperative behaviour. In the present paper we argue that this is because there is no reason to expect t hat internals are more cooperative than externals, or vice versa. Going bac k to the very definition of the locus of control concept, we hypothesise th at internals are likely to use both cooperative and competitive behaviour s trategically to further their own self-interest. In order to test this hypo thesis 39 subjects played three repeated prisoner's dilemma games. Their lo cus of control was measured by means of Rotter's I-E Locus of Control scale [Rotter, J.B. (1966). Generalized expectancies for internal versus externa l control of reinforcement. Psychological Monographs: General and Applied, 80, 609 pp.]. Our empirical findings indeed reveal that internals seem to h ave the adaptive capacity to instrumentally switch from cooperative to comp etitive behaviour and vice versa, in a prisoner's dilemma game. They also b ehave more opportunistically when the risk of retaliation is low. The resul ts also make clear that it is essential to study cooperative behaviour dyna mically. (C) 1999 Elsevier Science Ltd. All rights reserved.