Journal of Economics

, Volume 102, Issue 3, pp 237-262

Open Access This content is freely available online to anyone, anywhere at any time.

Social norms and the indirect evolution of conditional cooperation

  • Christian TraxlerAffiliated withMax Planck Institute for Research on Collective Goods Email author 
  • , Mathias SpichtigAffiliated withInstitute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam


We develop a model of social norms and cooperation in large societies. Within this framework we use an indirect evolutionary approach to study the endogenous formation of preferences and the co-evolution of norm compliance. The multiplicity of equilibria, which emerges in the presence of social norms, is linked to the evolutionary analysis: individuals face situations where many others cooperate as well as situations where a majority free-rides. The evolutionary adaptation to such heterogenous environments favors conditional cooperators, who condition their pro-social behavior on the others’ cooperation. As conditional cooperators react flexibly to their social environment, they dominate free-riders as well as unconditional cooperators.


Conditional cooperation Indirect evolution Social norms Heterogenous environments

JEL Classification

C70 Z13