The rational weakness of strong ties:Failure of group solidarity in a highly cohesive group of rational agents

Recent research (Flache 1996; Flache and Macy 1996) suggests a "weakness of strong ties." Cohesive social networks may undermine group solidarity, rather than sustain it. In the original analysis, simulations showed that adaptive actors learn cooperation in bilateral exchanges faster than cooperation in more complex group exchanges, favoring ties at the expense of the common good. This article uses game theory to demonstrate that cognitive simplicity is not a scope condition for the result. The game theoretical analysis identifies a new condition for the failure of group solidarity in a cohesive group. Task uncertainty may make rational cooperation increasingly inefficient in common good production. Accordingly, rational actors may increasingly sacrifice benefits from common good production in order to maintain social ties, as their dependence on peer approval rises.