Morals by Convention: The rationality of moral behaviour

The account of rational morality presented in Morals by Agreement is based, to a large extent, on the concept of constrained maximisation. Rational agents are assumed to have reasons to constrain their maximisation provided they interact with other similarly disposed agents. On this account, rational agents will internalise a disposition to behave as constrained maximisers. The assertion of constrained maximisation is problematic and unrealistic mainly because it does not explain how the process of internalisation occurs. I propose an amended version of constrained maximisation that is based on a conventional understanding of social behaviour and the social contract. Repeated interactions between rational agents lead to the creation of social conventions, which in turn serve as supportive mechanisms for behaviours that reinforce their stability. In addition, established social conventions facilitate and ensure information sharing, thus making it possible for conventional agents to know others' dispositions. The development and establishment of social conventions are best described and explained through an evolutionary account of social structures. The evolutionary account offers a more powerful and more realistic method of discussing cultural evolution, since it considers large populations over long periods of time and the interdependence between social structures and individual behaviour. In this context, information availability ensures that the most efficient conventions take over and maximising strategies become dominant. While for Gauthier moral behaviour depends on constrained maximisation, in the conventional account of morality it comes about as a result of repeated interactions between rational agents within the bounds of social conventions.