François Recanati Philosophie du langage et de l'esprit Collège de France Année 2023-2024 Colloque - Transparency, Indexicality and Consciousness : Transparency and A Posteriori Physicalism Colloque organisé par François Recanati, Professeur du Collège de France, chaire Philosophie du langage et de l'esprit Intervenant(s) Gregory Bochner, Collège de France According to a posteriori physicalism, the apparent gap between consciousness and the physical world has its source not in the nature of consciousness (ontological gap), but only in features of the concepts we use to think about our conscious experiences (epistemic gap). It would be true that phenomenal consciousness is physical, but this would be knowable only a posteriori, due to the semantics of phenomenal concepts. While a posteriori physicalism thus postulates that the link between phenomenal and physical knowledge is in some sense opaque, Kripke had argued that phenomenal knowledge should in some sense be transparent, and recent objections to a posteriori physicalism draw on the Kripkean thesis of transparency. In this talk, I seek to disentangle two relevant transparency theses on behalf of the a posteriori physicalist: the comparative transparency of mental content ("Boghossian's transparency") (Frege, Boghossian) and the thesis that phenomenal concepts reveal the essence of the experience they denote ("revelation") (Kripke, Chalmers, Nida-Rümelin, Goff). In a first part, I present my own compatibilist response to the conflict between externalism and Boghossian's transparency. The "pragmatic two-dimensionalism" it involves – which combines ideas from Lewis, Stalnaker, and Recanati – rejects the (Fregean) claim, common to all brands of what I call "classical two-dimensionalism," that what plays the role of mode of presentation is also what fixes reference. In a second part, I compare the roles of the two transparency theses in the knowledge argument and related cases. I argue that Boghossian's transparency plays a neglected yet essential role in epistemic arguments against physicalism. The most fundamental conflict these arguments highlight is really one between Boghossian's transparency, classical two-dimensionalism, and a posteriori physicalism. In the third and final part, I argue that classical two-dimensionalism (and the way it forces us to pose the problems) is the culprit. It becomes possible to maintain Boghossian's transparency and a posteriori physicalism once we endorse the pragmatic sort of two-dimensionalism I advertize.