In order to know what a belief is, 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. This is not entirely straightforward. Consider for instance 1. Tom thinks that he himself is the smartest and Tim believes the same 2. In 2001, Bill believed that some action had to be taken to save the rain forest and today he believes the same. What does Tim think? That he, Tim, is the smartest, or that Tom is? And what does Bill believe today? That action had to be taken in 2001 or that it has to be taken now? Both answers are intuitively acceptable. This has to be accounted for somehow. Building on Mark Richard's work on tense, Scott Soames 1 claims that the substitutional interpretation of the quantifiers is unable to account for the intended meaning of such statements as (2) and the validity of some inferences involving them. I will show that his argument is not convincing. Not only does the substitutional interpretation fare no worse than the objectual one, but it seems to be able to avoid a problem which could be seriously damaging for any account of the sameness of thoughts based on the notion of structured proposition. In the first section, I state the problem allegedly raised by tensed belief ascriptions to the substitutional interpretation of the quantifiers. In the second, Soames's argument is shown to be flawed. I also show that the content of the that-clause in (2) is not faithfully represented by any kind of structured proposition. Finally, I show how the substitutional interpretation can handle all such statements as (1) and (2) and the inferences involving them.