Replies to Wang, Speaks, and Pautz

I A logically valid argument preserves truth in virtue of form. A modally valid argument is such that, necessarily, if its premises are true then its conclusion is true. I say that logically valid arguments express modally valid arguments. That is, I say that the sentences that are the premises and conclusion of a logically valid argument express propositions, and those propositions are themselves the premises and conclusion of a modally valid argument. Wang objects: “Merricks’s view, unlike those of his opponents, cannot explain something that cries out for explanation: why any logical validity guarantees the existence of a corresponding modal validity” and “[Merricks] cannot explain why truth-preservation in virtue of form tracks necessitation relations between propositions.” She even says that given my view of the nature of propositions, it is a “huge coincidence” that logically valid arguments express modally valid arguments. My reply to Wang’s objection starts with X-Logic (cf. 64–5). By the lights of X-logic, ‘coyotes howl’ is a logical consequence of ‘dogs bark’. Relatedly, ‘coyotes howl’ is true in every model for X-logic in which ‘dogs bark’ is true. But X-logic is mistaken and its models defective. This is because, despite what X-logic says, ‘coyotes howl’ is not really a logical consequence of ‘dogs bark’. I think that one good reason for denying that ‘coyotes howl’ is a logical consequence of ‘dogs bark’ is that the truth of ‘dogs bark’ does not guarantee the truth of ‘coyotes howl’. So I conclude that an argument is logically valid only if the truth of its premises guarantees the truth of its conclusion (cf. 39–40; 61–71). In the book, I argue that the relevant guarantee is modal (64–71). But there is more than one way to understand this modal guarantee. The most widely endorsed way says that logically valid arguments are themselves (in virtue of their form) modally valid (61–2). But every logically valid argument has sentences as its premises and conclusion (34–60); no modally valid argument has sentences