Epistemic modals are standardly taken to be context-dependent quantifiers over possibilities. Thus sentences containing them get truth-values with respect to both a context and an index. But some insist that this relativization is not relative enough: `might'-claims, they say, only get truth-values with respect to contexts, indices, and—the new wrinkle—points of assessment (hence, CIA). Here we argue against such "relativist" semantics. We begin with a sketch of the motivation for such theories and a generic formulation of them. Then we catalogue (...) central problems that any such theory faces. We end by outlining an alternative story. (shrink)

It is a recurring mantra that epistemic must creates a statement that is weaker than the corresponding flat-footed assertion: It must be raining vs. It’s raining. Contrary to classic discussions of the phenomenon such as by Karttunen, Kratzer, and Veltman, we argue that instead of having a weak semantics, must presupposes the presence of an indirect inference or deduction rather than of a direct observation. This is independent of the strength of the claim being made. Epistemic must is therefore quite (...) similar to evidential markers of indirect evidence known from languages with rich evidential systems. We work towards a formalization of the evidential component, relying on a structured model of information states (analogous to some models used in the belief dynamics literature). We explain why in many contexts, one can perceive a lack of confidence on the part of the speaker who uses must. (shrink)

Counterfactuals are typically thought--given the force of Sobel sequences--to be variably strict conditionals. I go the other way. Sobel sequences and (what I call) Hegel sequences push us to a strict conditional analysis of counterfactuals: counterfactuals amount to some necessity modal scoped over a plain material conditional, just which modal being a function of context. To make this worth saying I need to say just how counterfactuals and context interact. No easy feat, but I have something to say on the (...) matter. (shrink)

The simplest story about modals—might, must, possibly, necessary, have to, can, ought to, presumably, likelier, and the rest—is also the canon: modals are context-dependent quantifiers over a domain of possibilities. Different flavors of modality correspond to quantification over different domains of possibilities. Logical modalities quantify over all the possibilities there are, physical modalities over possibilities compatible with the..

What we want to be true about ordinary indicative conditionals seems to be more than we can possibly get: there just seems to be no good way to assign truth-conditions to ordinary indicative conditionals. Some take this argument as reason to make our wantings more modest. Others take it to show that indicative conditionals don't have truth-conditions in the first place. But we have overlooked two possibilities for assigning truth-conditions to indicatives. What's more, those possibilities deliver what we want and (...) turn out to be equivalent. CiteULike Connotea Del.icio.us Digg Reddit Technorati What's this? (shrink)

way on the information available in the contexts in which they are used, it’s not surprising that there is a minor but growing industry of work in semantics and the philosophy of language concerned with the precise nature of the context-dependency of epistemically modalized sentences. Take, for instance, an epistemic might-claim like..

This paper has three main goals. First, to motivate a puzzle about how ignorance-expressing terms like maybe and if interact: they iterate, and when they do they exhibit scopelessness. Second, to argue that there is an ambiguity in our theoretical toolbox, and that exposing that opens the door to a solution to the puzzle. And third, to explore the reach of that solution. Along the way, the paper highlights a number of pleasing properties of two elegant semantic theories, explores some (...) meta-theoretic properties of dynamic notions of meaning, dips its toe into some hazardous waters, and offers characterization theorems for the space of meanings an indicative conditional can have. (shrink)

Moore's paradox pits our intuitions about semantic oddnessagainst the concept of truth-functional consistency. Most solutions tothe problem proceed by explaining away our intuitions. But``consistency'' is a theory-laden concept, having different contours indifferent semantic theories. Truth-functional consistency is appropriateonly if the semantic theory we are using identifies meaning withtruth-conditions. I argue that such a framework is not appropriate whenit comes to analzying epistemic modality. I show that a theory whichaccounts for a wide variety of semantic data about epistemic modals(Update Semantics) buys (...) us a solution to Moore's paradox as a corollary.It turns out that Moorean propositions, when looked at through the lenseof an appropriate semantic theory, are inconsistent after all. (shrink)

In "*Must* ...stay ...strong!" (von Fintel & Gillies 2010) we set out to slay a dragon, or rather what we called The Mantra: that epistemic *must* has a modal force weaker than expected from standard modal logic, that it doesn't entail its prejacent, and that the best explanation for the evidential feel of *must* is a pragmatic explanation. We argued that all three sub-mantras are wrong and offered an explanation according to which *must* is strong, entailing, and the felt indirectness (...) is the product of an evidential presupposition carried by epistemic modals. Mantras being what they are, it is no surprise that each of the sub-mantras have been given new defenses. Here we offer them new problems and update our picture, concluding that *must* is (still) strong. (shrink)

Obligation describing language is hooked up with preference, a relation of what-is-better-than-what. But ordinary situations underdetermine such relations of what-is-better-than-what. Even so, there are plainly true sentences describing our obligations in those situations. This mismatch is trouble-making and getting out of the trouble requires either giving up the easy link between “ought” and preference or re-thinking the kind of things preferences can be.

Chalmers' anti-materialist arguments are an interesting twist on a well-known argument form, and his naturalistic dualism is exciting to contemplate. Nevertheless, we think we can save materialism from the Chalmerian attack. This is what we do in the present paper.

This is a handbook article about conditionals.

“Any theory of conditionals has consequences for less-than-certain judgements. Something is proposed of the form: If A, B is true iff A*B. If a clear-headed person, free from confusions of a logical, linguistic or referential sort, can be nearly sure that A*B yet far from sure that if A, B, or vice versa, then this is strong evidence against the proposal.” (Edgington 1995/2007).

We must change our beliefs, and change them in particular ways, in response to new information. But not all changes are created equal: some are rational changes, some not. The Problem of Epistemic Change is the problem of specifying the rational constraints on how the epistemic state of an agent ought to change in the face of new information. This dissertation is about the philosophical and logical investigation of rational belief change. I start by arguing that the familiar foundations---coherence distinction (...) from static epistemology does not adequately carve up the logical space of theories of epistemic change. It is better to think of theories as being loosely ordered along a continuum from more to less foundational. The ordering, however, is "clumpy" in the sense that there are large regions in the ordering which remain unexplored. I then present and develop GDEC which is a new foundations model of belief revision that fills a gap in this ordering of theories of epistemic change. The key insight in GDEC is that belief that...is ambiguous between the attitudes of accept that...and expect that... GDEC respects the difference and how it matters for epistemic change. I show that GDEC is a genuine competitor to the AGM theory of belief revision in the sense that the two approaches are incompatible. The remainder of the dissertation is devoted to exploring the logical dynamics of GDEC and the models I develop here which extend it by applying them to a series of richer epistemic environments. I show how puzzles and paradoxes which confound other theories of belief revision are solved in a unified way by GDEC and its extensions. In particular, I give solutions to Moore's Paradox, Fuhrmann's Impossibility Theorem, the Reduction Problem of Epistemic Conditionals, and the Gardenfors Impossibility Theorem. (shrink)

Features of experimental design impose auxiliary hypotheses on experimenters. Hertwig & Ortmann rightly argue that the ways some variables are implemented in psychology cloud results, whereas the different implementations in economics provide for more robust results. However, not all design variables support this general conclusion. The repetition of trials may confuse results depending on what theory is being tested. We explore this in the case of simple bargaining games.

Sly Pete and Mr. Stone are playing poker on a Mississippi riverboat. It is now up to Pete to call or fold. My henchman Zack sees Stone’s hand, which is quite good, and signals its content to Pete. My henchman Jack sees both hands, and sees that Pete’s hand is rather low, so that Stone’s is the winning hand. At this point, the room is cleared. A few minutes later, Zack slips me a note which says “If Pete called, he (...) won,” and Jack slips me a note which says “If Pete called, he lost”. (shrink)