The 'substitution argument' purports to demonstrate the falsity of Russellian accounts of belief-ascription by observing that, e.g., these two sentences: (LC) Lois believes that Clark can fly. (LS) Lois believes that Superman can fly. could have different truth-values. But what is the basis for that claim? It seems widely to be supposed, especially by Russellians, that it is simply an 'intuition', one that could then be 'explained away'. And this supposition plays an especially important role in Jennifer Saul's defense of (...) Russellianism, based upon the existence of an allegedly similar contrast between these two sentences: (PC) Superman is more popular than Clark. (PS) Superman is more popular than Superman. The latter contrast looks pragmatic. But then, Saul asks, why shouldn't we then say the same about the former? The answer to this question is that the two cases simply are not similar. In the case of (PC) and (PS), we have only the facts that these strike us differently, and that people will sometimes say things like (PC), whereas they will never say things like (PS). By contrast, there is an argument to be given that (LS) can be true even if (LC) is false, and this argument does not appeal to anyone's 'intuitions'. The main goal of the paper is to present such a version of the substitution argument, building upon the treatment of the Fregan argument against Russellian accounts of belief itself in "Solving Frege's Puzzle". A subsidiary goal is to contribute to the growing literature arguing that 'intuitions' simply do not play the sort of role in philosophical inquiry that so-called 'experimental philosophers' have supposed they do. (shrink)

For years philosophers argued for the existence of distinct yet materially coincident things by appealing to modal and temporal properties. For instance, the statue was made on Monday and could not survive being flattened; the lump of clay was made months before and can survive flattening. Such arguments have been thoroughly examined. Kit Fine has proposed a new set of arguments using the same template. I offer a critical evaluation of what I take to be his central lines of reasoning.

In a 1997 paper Jennifer Saul adduces various examples of simple sentences in which the substitution of one co-referential singular term for another appears to be invalid. I address the question of whether anti-substitution is logically justified by examining the validity and soundness of substitution of co-referential singular terms in three simple-sentence arguments each exhibiting a different logical structure. The result is twofold. First, all three arguments are valid, provided Leibniz’s Law is valid with respect to simple sentences . Thus, (...) as far as these arguments are concerned, there is no logical problem with substitution in simple sentences. Second, two of the arguments cannot be sound, because their respective sets of premises are inconsistent. Thus, it would be logically irrational to commit oneself to all the premises of the respective arguments. To the extent that the origin of Saul’s puzzles is in logic , I suggest, tentatively, that substitution may appear to be invalid because the issues of validity and soundness have not been kept separate. I then consider in depth Saul’s first sentence, “Clark Kent enters a phone booth and Superman exits”. Obviously, two-way substitution is trivially valid, if the expressions are co-referential semantically proper names, the conclusion being but a rephrasing of the premise. However, I argue that a non-trivial semantic analysis of this sentence should take account of the diachronicity of Clark Kent’s entrance and Superman’s exit while preserving the internal link between being Superman and being Clark Kent. I propose the following. ‘Superman’ and ‘Clark Kent’ refer to two distinct individual concepts. “Superman is Clark Kent” then no longer expresses the self-identity of an individual bearing two names, but that two named concepts are held together by the requisite relation: wherever and whenever someone falls under the concept of Superman the same individual also falls under the Clark Kent concept, whereas there are exceptions to the converse. This semantic analysis always validates the substitution of ‘Clark Kent’ for ‘Superman’, but validates the substitution of ‘Superman’ for ‘Clark Kent’ only if the additional condition is met that somebody should fall under the Superman concept when Clark Kent. (shrink)

In this paper I concern myself with The Superman Puzzle. I argue that the descriptive content associated with proper names, besides determining the proper name’s reference, function as truth-conditionally relevant adjuncts which can be used to express a manner, reason, goal, time or purpose of action. In that way a sentence with a proper name ‘NN is doing something’ could be understood as ‘NN is doing something as NN’. I argue that the substitution of names can fail on modified readings (...) because the different descriptive content of proper names modifies the main predicate differently. Here I present a formal representation of modified predicates which allows one to model intuitively the different truth-conditions of sentences from The Puzzle. (shrink)