[Spontaneous formation of generalized exchange system: an experimental study of discriminating altruism]

Recent computer simulation studies (Takahashi & Yamagishi, 1995, 1996) suggest the possibility that altruists outperform egoists, and the key to their advantage is a strategy called Downward OFT. The strategy calls for acting always altruistically, at the same time selecting as the target of the altruism the most altruistic person among potential recipients. The main purpose of this study was to examine whether people actually follow Downward OFT in a situation where no direct reciprocity was possible. Results were as follows: (1) Pure generalized exchange (i.e., unilateral recourse giving) did emerge and persisted over forty-five trials. (2) Subjects selected other altruists as recipients of their unilateral resource giving. (3) The tendency of altruistic subjects to discriminate among potential recipients of their altruism was stronger than that of self-interested subjects. (4) Subjects who unilaterally gave more resource ended up with more profit (resource received minus resource given) than those who gave less.