Online research in philosophy

I want to discuss a puzzle about the semantics of epistemic modals, like “It might be the case that” as it occurs in “It might be the case that Goldbach’s conjecture is false.”1 I’ll argue that the puzzle cannot be adequately explained on standard accounts of the semantics of epistemic modals, and that a proper solution requires relativizing utterance truth to a context of assessment, a semantic device whose utility and coherence I have defended elsewhere for future contingents (MacFarlane..

Contextualists, about a given type of expression, claim that the contribution that expression makes to the content or truth value of an assertion depends on the context in which this assertion is made, whereas invariants deny this. Recently, arguments have been given favoring invariantism for a number of expressions for which contextualism had previously been favored, including predicates of personal taste (e.g., ‘tasty,’ ‘dreamy’),1 epistemic modals (‘might,’ ‘must’),2 deontic modals (‘ought,’ ‘may’),3 probability operators (‘probably,’ ‘certainly’),4 and indicative conditionals,5 among others.6 Invariantists have prominently argued that their view is preferable to contextualism because only their view accounts for disagreement and closely related phenomena. For invariantism seems to allow, correctly, that Popeye and Bluto disagree when Popeye says ‘spinach is tasty’ and Bluto says ‘spinach is not tasty,’ whereas contextualism seems to predict that they do not thereby disagree, since the proposition Popeye affirms differs from the proposition Bluto denies. More generally, if we define a contested sentence as a sentence containing one of the contested expressions (‘tasty’, ‘might’, ‘ought’ etc.) but no other contextsensitive expressions, invariantism seems to entail that the following is true, whereas contextualism seems to entail that it is false.

Schulz has shown that the suppositional view of indicative conditionals leads to a corresponding view of epistemic modals. But his case backfires: the resulting theory of epistemic modals gets the facts wrong, and so we end up with a good argument against the suppositional view. I show how and why a dynamic view of indicative conditionals leads to a better theory of epistemic modals.

This paper explores the possibility of supplementing the suppositional view of indicative conditionals with a corresponding view of epistemic modals. The most striking feature of the suppositional view consists in its claim that indicative conditionals are to be evaluated by conditional probabilities. On the basis of a natural link between indicative conditionals and epistemic modals, a corresponding thesis about the probabilities of statements governed by epistemic modals can be derived. The paper proceeds by deriving further consequences of this thesis, in particular, the logic of epistemic modals and their logical interaction with indicative conditionals are studied.

Puzzles about sentences containing expressions of certain sorts, such as predicates of personal taste, epistemic modals, and ‘know’, have spawned families of views that go by the names of Contextualism and Relativism. In the case of predicates of personal taste, which I will be focusing on, contextualist views say that the contents of sentences like “Uni is delicious” and “The Aristocrats is hilarious” vary somehow with the context of utterance. Such a sentence semantically expresses different propositions in different contexts, depending on what standard or perspective (or whose standard or perspective) is implicitly adverted to. According to relativist views, the propositional content of such a sentence is fixed, but what it takes for that proposition to be true varies somehow with the context, depending on the relevant standard or perspective. I will argue that such views are neither well supported by the data nor well motivated by the puzzles themselves. Even so, there is an element of truth in each. I will sketch an alternative view, dubbed Radical Invariantism, according to which the appearance of context sensitivity is illusory. Rather than impute either kind of context sensitivity to these sentences or to their contents, Radical Invariantism says that these sentences are distinguished by what they don’t do. Because they are not explicitly relativized, they leave a certain semantic slack. They fall short of fully expressing a proposition, instead expressing merely a “propositional radical.” We can explain away the appearance of semantic context sensitivity pragmatically, by taking into account facts about how, and under what conditions, speakers who use or encounter these sentences manage to pick up the slack. This can occur in either of two ways. Speakers either take a certain standard or perspective as understood, or else they treat the sentence as if it expresses a standard- or perspective-independent proposition even though it does not..

In “Epistemic Modals,” Seth Yalcin argues that what explains the deficiency of sentences containing epistemic modals of the form ‘p and it might be that not-p’ is that sentences of this sort are strictly contradictory, and thus are not instances of a Moore-paradox as has been previous suggested. Benjamin Schnieder, however, argues in his Yalcin’s explanation of these sentences’ deficiency turns out to be insufficiently general, as it cannot account for less complex but still defective sentences, such as ‘Suppose it might be raining.’ Consequently, Schnieder proposes his own, expressivist treatment of epistemic modals which he thinks can explain the deficiency of both the original sentence type as well as more complex cases of embedded sentences containing epistemic modals. In this study, I argue that although Schnieder is right to draw our attention to the explanatory failure of Yalcin’s account, we aren’t forced to adopt Schnieder’s expressivist account of epistemic modals. I defend instead a contextualist-friendly alternative which explains the deficiencies of all the relevant sentence types, while avoiding both the defects of Yalcin’s account and the intuitive costs of expressivism.

Recently, Yalcin (Epistemic modals. Mind, 116 , 983–1026, 2007) put forward a novel account of epistemic modals. It is based on the observation that sentences of the form ‘ & Might ’ do not embed under ‘suppose’ and ‘if’. Yalcin concludes that such sentences must be contradictory and develops a notion of informational consequence which validates this idea. I will show that informational consequence is inadequate as an account of the logic of epistemic modals: it cannot deal with reasoning from uncertain premises. Finally, I offer an alternative way of explaining the relevant linguistic data.

A very simple contextualist treatment of a sentence containing an epistemic modal, e.g. a might be F, is that it is true iff for all the contextually salient community knows, a is F. It is widely agreed that the simple theory will not work in some cases, but the counterexamples produced so far seem amenable to a more complicated contextualist theory. We argue, however, that no contextualist theory can capture the evaluations speakers naturally make of sentences containing epistemic modals. If we want to respect these evaluations, our best option is a relativist theory of epistemic modals. On a relativist theory, an utterance of a might be F can be true relative to one context of evaluation and false relative to another. We argue that such a theory does better than any rival approach at capturing all the behaviour of epistemic modals.

A very simple contextualist treatment of a sentence containing an epistemic modal, e.g. a might be F, is that it is true iff for all the contextually salient community knows, a is F. It is widely agreed that the simple theory will not work in some cases, but the counterexamples produced so far seem amenable to a more complicated contextualist theory. We argue, however, that no contextualist theory can capture the evaluations speakers naturally make of sentences containing epistemic modals. If we want to respect these evaluations, our best option is a relativist theory of epistemic modals. On a relativist theory, an utterance of a might be F can be true relative to one context of evaluation and false relative to another. We argue that such a theory does better than any rival approach at capturing all the behaviour of epistemic modals.

I develop a new argument for an expressivist account of epistemic modals, which starts from a puzzle about epistemic modals which Seth Yalcin recently presented. I reject Yalcin's own solution to the puzzle, and give a better explanation based on expressivism concerning epistemic modals. I also address two alleged problems for expressivism: do embeddings of epistemic modals pose a serious threat to expressivism, and how can expressivism account for disagreements about statements containing epistemic modals?