Prior's puzzle is standardly taken to be the puzzle of why, given the assumption that that-clauses denote propositions, substitution of "the proposition that P" for "that P" within the complements of many propositional attitude verbs is invalid. I show that Prior's puzzle is much more general than is ordinarily supposed. There are two variants on the substitutional form of the puzzle-a quantificational variant and a pronominal variant-and all three forms of the puzzle arise in a wide range of verbal complements, rather than merely in the complements of propositional attitude verbs. The generalized puzzle shows that a range of proposed solutions to the original puzzle fail, or are radically incomplete, and also reveals the connections between Prior's puzzle and debates over the nature of semantic types and higher-order quantification. I go on to develop a novel, higher-order solution to the generalized form of the puzzle, and I argue that this higher-approach is superior to its first-order alternatives.
• Justin D'Ambrosio(1) a. Sally fears that Fido bites.b. Sally fears the proposition that Fido bites.The standard theory tells us that "that fido bites" refers to a proposition. It also seems clear that "the proposition that Fido bites" refers to a proposition-indeed, the very same proposition. And yet (1-a) can be true while (1-b) is false-Sally does not fear an abstract object. We may call this Prior's puzzle, after Arthur Prior [1971, p. 16], who first formulated it.This paper first shows that Prior's puzzle is not just a puzzle concerning substitutions such as the one above. Rather, the failure of such substitutions to preserve truth is a special case of a puzzle that is much more general along two dimensions. First, the substitutional puzzle has both quantificational and pronominal variants that have the same source and warrant the same solution as the original form. Thus, Prior's puzzle has nothing specifically to do with substitution. Second, all three of these forms of the puzzle arise in the complements of all kinds of verbs. Thus, Prior's puzzle has nothing specifically to do with that-clauses or propositional attitude verbs.This generalization has several important consequences. First, the generalized puzzle shows that a wide range of proposed solutions to Prior's puzzle fail, or are radically incomplete. Many such proposals apply only to the substitutional puzzle, and cannot be generalized to its quantificational or pronominal variants. Other proposals apply only to the case of propositional attitudes, but cannot be extended to solve the puzzle as it arises in other verbal complements.Still other views fail in both of these ways.Second, this generalization reveals the way in which Prior's puzzle is deeply intertwined with debates over the nature of semantic types and the status of higher-order quantification. In particular, one's approach to solving the generalized form of Prior's puzzle is determined by, and also reveals, one's views on two questions that are fundamental to semantic theorizing: whether...
