On the Sameness of Thoughts. Substitutional Quantifiers, Tense, and Belief

In order to know what a belief is – and, more generally, a thought, i.e., the content of a propositional attitude – we need to know when it is appropriate to say that two subjects (or the same subject at two different times) believe(s) the same or entertain the same thought. Building on Mark Richard’s work on tense, Scott Soames claims that the substitutional interpretation of the quantifiers is unable to account for the intended meaning of some inferences involving belief retention. I will show that his argument is not convincing. Not only does the substitutional interpretation fare no worse than the objectual one, but it can answer the problem of the sameness of thoughts, which the objectual one and the attendant apparatus of propositions and properties seem unable to deal with.