François Recanati Philosophie du langage et de l'esprit Collège de France Année 2023-2024 Colloque - Transparency, Indexicality and Consciousness : Externalism, Transparency, and the (In)transitivity of Coordination Colloque organisé par François Recanati, Professeur du Collège de France, chaire Philosophie du langage et de l'esprit Intervenant(s) Aidan Gray, University of Illinois, Chicago Following recent usage, I use 'coordination' to refer to the relation that Fregeans have conceived of as sameness of sense. To a first approximation, representations are coordinated when the fact they are about the same object is transparent to their subject. Coordination is the relation that must hold between representations for it to be rational to 'trade on the identity' of their referents. In this talk, I examine the interaction between two questions: - Is coordination transitive? - What features of attitude states are shared between qualitative duplicates? My focus is Boghossian's discussion of slow-switching. The crux of Boghossian's argument is that content externalism entails that we cannot attribute coordination in certain confusion cases in which a subject is intuitively rational in trading on identity. I show that this conclusion is only forced on us if coordination is transitive. If coordination is intransitive, we can describe confused subjects in a way that respects the reference of their thoughts and the rationality of their inferences. The challenge for developing a view of this kind is to characterize the rational upshot of intransitive coordination. I develop a logical system that models this. It follows from this account that when coordination is (de facto) transitive, rational relations are classical. But when coordination is intransitive, rational relations break down in a particular way: individually valid rational transitions do not always sum to globally valid transitions.