Abstract

Driven by the intuition that the propositions expressed by a=a and a=b, where ‘a’ and ‘b’ are codesignative names, differ in cognitive value, philosophers constructing theories of beliefs and belief attributions have been attracted to elements from both Frege’s and Russell’s theories. This, I will argue, has had the consequence that some of the theories entail that it is a necessary condition for making the astronomical discovery that Hesperus is Phosphorus that we make a mental discovery about our representations of Venus. I will discuss the motivation behind Frege’s and Russell’s views and present an example which makes it clear that we can make astronomical discoveries prior to making the mental discovery that two names, or two mental representations, are of the same object. The upshot of the discussion is that we should not build modes of presentation into propositions.