Abstract
Two experiments extended and tested Deutsch's (1993) theory of competition effects. A knowledge structure approach predicted that people view competitive situations as inherently more aggressive than cooperative ones. Furthermore, it was predicted that leading people to think of an ambiguously aggressive situation in competitive terms would increase aggressive behavior. In Experiment 1, knowledge structures of competitive situations had more aggressive content than cooperative ones. In Experiment 2, competition-primed subjects unnecessarily killed more video game characters (Mario Brothers) than cooperation-primed subjects. The increase in kill ratio occurred in the absence of changes in hostility, friendliness, or liking for one's game partner. Implications for understanding cooperation and competition, and for further research on such "affectless agression," were discussed.