Normative Structures in Trust Management

The modelling of trust for the purpose of trust management gives rise to a puzzle that opens up fundamental questions concerning the relationship between trust and calculative reason as the basis for cooperation. It is argued that, ironically, trust management seem not to maximise trust but, instead, to reduce the need for trust. This conclusion is used to argue that the normative aspects of trust must be given a central role in the modelling of trust and trust management. The following question is addressed: What can an agent R infer about the future actions of another agent E, if R assumes that E is trustworthy? It is suggested that a generalised version of Barwise and Seligman’s theory of information flow can be used to model the role of normative structures in reasoning in trust relationships. Implications for trust management are discussed.