Thinking Alike: Five Essays on the Publicity of Thought = Pensar el mateix: cinc assaigs sobre la “publicitat” del pensament

In this dissertation, I have investigated several philosophical puzzles associated to the thesis that thoughts are public, i.e. that in successful instances of communication, understanding, and in cases where thinkers are in genuine agreement with each other, the relevant thinkers accept the same thoughts. In chapter 1, I showed that this thesis seems difficult to uphold in the face of cases involving indexical expressions. When subjects successfully communicate with indexical expressions, they are nonetheless disposed to perform different actions, and thus we have reason to deny that they accept exactly the same thoughts. In chapter 2, I showed that this thesis is in conflict with the thesis that thoughts must track the cognitive profile of our attitudes (‘Frege’s Constraint’). In chapter 3, I showed that this thesis is in conflict with a minimal version of semantic internalism and that even the most conservative way of trying to make these two theses compatible involves weakening the claim that thought is public in the sense previously defined. In chapter 4, I investigated criteria of successful communication and argued against one based on match of referential content plus absence of false beliefs. In its place, I suggested we go back to criteria based on match of modes of presentation (thoughts) or successful recognition of the speaker’s referential intentions. In chapter 5, I argued that thought’s publicity cannot be fully accommodated by extant relationist theories of thoughts and concepts. One way to frame the most general conclusion of this dissertation is that it is futile to try to individuate an intersubjective notion of thought which is transitive, or which is equally useful from an intrapersonal perspective. If we have any reason for carving up an intersubjective notion of thought – and not even this is clear, as far as this dissertation is concerned – then it will most likely be orthogonal to the usual subjective one