Are the recent findings of Behavioural Game Theory (BGT) on unselfish behaviours relevant for the progress of game theory? Is the methodology of BGT, centred around the attempt to study theoretically players’ utility functions in the light of the feedback that experimental evidence can produce on the theory, a satisfactory one? Or is the creation of various types of ‘social preferences’ just wasteful tinkering? This article compares BGT with the methodology of Rational Game Theory (RGT). BGT is viewed as a (...) more promising and constructive approach, with regard to the relationship between experimental data and theoretical modelling. However, I also argue that today RGT and BGT are closer to one another than often thought. (shrink)