1 Episteme Symposium on Group Agency

The central theme of Gerald Gaus’s commentary is the understanding of rationality underlying our book. His discussion is framed around the contrast between classical, universalist understandings of rationality, and their more recent, psychologically and evolutionarily informed rivals. He calls the former “constructivist ” and the latter “ecological”. He argues that our book is firmly grounded in a classical, constructivist understanding, and that this, in turn, makes it vulnerable to a number of criticisms. In particular, he argues that, despite our acknowledgment that there is no “one size fits all” organizational design for a group agent, our theory gives insufficient attention to the context-specificity of the rationality requirements a group agent should satisfy – something he suggests would be better captured by an ecological approach. In this reply, we first explain how we see the distinction between “classical ” and “ecological ” understandings of rationality and relate the distinction to our project. We then address two of Gaus’s more specific criticisms: his criticism of the claim that group agents must satisfy “robust group rationality ” (which, technically, subsumes “universal domain ” and “collective rationality”), and his criticism that our judgment-aggregatio