Conclusions and Implications
This final chapter summarizes the main propositions and concludes that punishment originates from moral emotions, stimulates and sustains cooperation, and shapes the social life of humans both within and between groups. Punishment hence is a hardwired moral instinct that evolved to stimulate cooperation in small groups. The remainder of the chapter discusses the practical implications of these insights for public policy, courts of law, organizations, schools, sports, and any other setting that requires punishment to stimulate cooperation. The main implications are (1) when punishing, fairness is more successful than severity in establishing cooperation; (2) for punishment to be effective, one should discourage big egos and personal vendettas, and leave punishment up to independent third parties; (3) punishment is most effective if combined with restorative justice; and (4) one should try to avoid inter-group bias by relying on reason instead of emotions when assigning punishment.