François Recanati Philosophie du langage et de l'esprit Collège de France Année 2023-2024 Colloque - Indexical Dynamics : Content-Bearers and Indexicality Colloque organisé par François Recanati, Professeur du Collège de France, chaire Philosophie du langage et de l'esprit Intervenant(s) Tadeusz Ciecierski, University of Warsaw One potential conservative reaction to the concept of indexicality of content involves a theory that treats indexicality as a property inherent to content-bearers. While this view aligns intuitively with linguistic cases, as indexicality is commonly seen as a property of expressions, it requires further elucidation when applied to intentional (mental) states as content-bearers. In this paper, I aim to present a theory that elucidates the indexicality of attitudes and other mental states by examining the properties of the bearers or vehicles of content. The theory I shall present departs from an account of indexicality rooted in Frege's philosophy, specifically a hybrid expression view (cf. Frege, 1956). Various versions of this view (cf. Künne, 1992; Künne, 2010; Textor, 2007, 2015; Kripke, 2008; Penco, 2013; Ciecierski, 2019) share the common feature of conceiving content-bearers as complex objects. These objects, in addition to narrowly conceived components (linguistic expressions in the case of utterances or mental representations/forms in the case of mental states), consist of contextual elements such as the speaker, time of utterance, or place of utterance. Recognizing the differences in these content-bearers allows for the expression of a single standard and non-indexical content through appropriately contextually coordinated bearers, while different non-indexical contents are expressible by uncoordinated bearers. One potential advantage of this theory is its uniform treatment of linguistic and mental indexicality. However, the theory is not immune to objections (cf. Perry, 1977, 491; Kaplan, 1989, 538). A notable challenge arises in explaining the intuition that an individual who loses track of time, like Rip van Winkle, shares the same thought when considering that today is sunny (on a day d in 1789) and when thinking that yesterday was sunny (on a day d' in 1800). One response to this challenge (cf. Tichy, 1986, 40; Textor, 2011, 168) suggests that a person who loses track of time fails to accurately capture the content of the thought that yesterday was sunny (on a day d' in 1800). While successful in addressing the challenge, this response rejects the initial intuition entirely and contradicts the idea of the transparency of mental content. To address this problem, I propose the internalistic version of the hybrid expression view of indexicality. While the standard hybrid expression view adopts an externalistic perspective, claiming that a hybrid expression (content-bearer) consists of a vehicle and an aspect of the relevant externally existing context of utterance (Externalistic Hybridity Claim), the internalistic version posits that a hybrid expression consists of a vehicle and an aspect of the relevant mental representation of a possible context of utterance (Internalistic Hybridity Claim). Accepting Internalistic Hybridity allows for a nuanced treatment of cases where individuals are "lost in time." For instance, Rip van Winkle, while entertaining the thought that yesterday was sunny, grasps the content of the hybrid representation consisting of a vehicle (the mental counterpart of "yesterday") and the representation of the time of utterance corresponding to d+1 1789. Consequently, he fails to grasp the content that it was sunny on d'-1 1800, but he apprehends a different yet related content. His mistake in content attribution is a result of a factual error—selecting the wrong context as actual. This analysis aligns with the intuitive transparency of mental content: Rip van Winkle grasps the appropriate content and maintains a disposition to differentiate between