Prolegomena for a Logic of Trust and Reputation

Reputation and trust are useful instruments in multi-agent systems to evaluate agent behaviour. Most of the works on trust and reputation adopt a quantitative representation of these concepts. Trust and reputation are commonly simplified to a numerical representation loosing important properties of these concepts. The aim of this paper is therefore to provide a qualitative formal analysis of trust and reputation on the basis of cognitive primitives. The proposed formalization is strongly inspired by Castelfranchi and Falcone’s model of social trust. The concepts of trust and reputation are built from the same bricks (goal, capability, power, and willingness) but in a different scope (individual belief vs. collective belief).