Traditional procedures for rational updating fail when it comes to self-locating opinions, such as your credences about where you are and what time it is. This paper develops an updating procedure for rational agents with self-locating beliefs. In short, I argue that rational updating can be factored into two steps. The first step uses information you recall from your previous self to form a hypothetical credence distribution, and the second step changes this hypothetical distribution to reflect information you have genuinely (...) learned as time has passed. While the second step resembles traditional procedures of updating by conditionalization, the first is best understood by analogy to traditional models of how agents transmit self-locating opinions through ordinary interpersonal communication. (shrink)

This paper defends an account of full belief, including an account of its relationship to credence. Along the way, I address several familiar and difficult questions about belief. Does fully believing a proposition require having maximal confidence in it? Are rational beliefs closed under entailment, or does the preface paradox show that rational agents can believe inconsistent propositions? Does whether you believe a proposition depend partly on your practical interests? My account of belief resolves the tension between conflicting answers to (...) these questions that have been defended in the literature. In addition, my account complements fruitful probabilistic theories of assertion and knowledge. (shrink)

What do normative terms like “obligation” mean in legal contexts? On one view, which H.L.A. Hart may have endorsed, “obligation” is ambiguous in moral and legal contexts. On another, which is dominant in jurisprudence, “obligation” has a distinctively moralized meaning in legal contexts. On a third view, which is often endorsed in philosophy of language, “obligation” has a generic meaning in moral and legal con- texts. After making the nature of and disagreements between these views precise, I show how linguistic (...) data militates against both rivals to the generic meaning view, and argue that this has significant implications for jurisprudence. (shrink)

This paper explores the idea that a semantics for ‘ought’ should be neutral between different ways of deciding what an agent ought to do in a situation. While the idea is, I argue, well-motivated, taking it seriously leads to surprising, even paradoxical, problems for theorizing about the meaning of ‘ought’. This paper describes and defends one strategy—a form of Expressivism for the modal ‘ought’—for navigating these problems.

This paper develops an account of the meaning of `ought', and the distinction between weak necessity modals (`ought', `should') and strong necessity modals (`must', `have to'). I argue that there is nothing specially ``strong'' about strong necessity modals per se: uses of `Must p' predicate the (deontic/epistemic/etc.) necessity of the prejacent p of the actual world (evaluation world). The apparent ``weakness'' of weak necessity modals derives from their bracketing whether the necessity of the prejacent is verified in the actual world. (...) `Ought p' can be accepted without needing to settle that the relevant considerations (norms, expectations, etc.) that actually apply verify the necessity of p. I call the basic account a modal-past approach to the weak/strong necessity modal distinction (for reasons that become evident). Several ways of implementing the approach in the formal semantics/pragmatics are critically examined. The account systematizes a wide range of linguistic phenomena: it generalizes across flavors of modality; it elucidates a special role that weak necessity modals play in discourse and planning; it captures contrasting logical, expressive, and illocutionary properties of weak and strong necessity modals; and it sheds light on how a notion of `ought' is often expressed in other languages. These phenomena have resisted systematic explanation. In closing I briefly consider how linguistic inquiry into differences among necessity modals may improve theorizing on broader philosophical issues. (shrink)

I present two Triviality results for Kratzer's standard “restrictor” analysis of indicative conditionals. I both refine and undermine the common claim that problems of Triviality do not arise for Kratzer conditionals since they are not strictly conditionals at all.

At the heart of the Bayesianism is a rule, Conditionalization, which tells us how to update our beliefs. Typical formulations of this rule are underspecified. This paper considers how, exactly, this rule should be formulated. It focuses on three issues: when a subject’s evidence is received, whether the rule prescribes sequential or interval updates, and whether the rule is narrow or wide scope. After examining these issues, it argues that there are two distinct and equally viable versions of Conditionalization to (...) choose from. And which version we choose has interesting ramifications, bearing on issues such as whether Conditionalization can handle continuous evidence, and whether Jeffrey Conditionalization is really a generalization of Conditionalization. (shrink)

Todd (2016) proposes an analysis of future-directed sentences, in particular sentences of the form 'will(φ)', that is based on the classic Russellian analysis of definite descriptions. Todd's analysis is supposed to vindicate the claim that the future is metaphysically open while retaining a simple Ockhamist semantics of future contingents and the principles of classical logic, i.e. bivalence and the law of excluded middle. Consequently, an open futurist can straightforwardly retain classical logic without appeal to supervaluations, determinacy operators, or any further (...) controversial semantical or metaphysical complication. In this paper, we will show that this quasi-Russellian analysis of 'will' both lacks linguistic motivation and faces a variety of significant problems. In particular, we show that the standard arguments for Russell's treatment of definite descriptions fail to apply to statements of the form 'will(φ)'. (shrink)

Imperatives are linguistic devices used by an authority (speaker) to express wishes, requests, commands, orders, instructions, and suggestions to a subject (addressee). This essay's goal is to tentatively address some of the following questions about the imperative. -/- METASEMANTIC. What is the menu of options for understanding fundamental semantic notions like satisfaction, truth-conditions, validity, and entailment in the context of imperatives? Are there good imperative arguments, and, if so, how are they to be characterized? What are the options for understanding (...) the property that an account of good imperative arguments is supposed to track? What constraints on a semantic analysis of the imperative do different positions on the metasemantic issues impose? -/- SEMANTIC. How might we implement metasemantic postures in a rigorous formal system? How much can we do using familiar tools from deontic modal logic? How much leverage over semantic questions can we gain by introducing tools from natural language semantics—ordering sources, dyadic modal operators, salient alternatives, and the like—into a formal semantics for an imperative object language? How much leverage can we gain by introducing tools from rather less-utilized areas of modal logic—devices for representing actions and planning in time, modal operators constructed from action-terms, and the like—into the analysis? -/- DYNAMIC. How do imperatives succeed in performing the speech acts they are used to perform? How do imperatives update discourses? How can we leverage an account of imperative discourse update in giving a dynamic semantics for the imperative? Is there anything about the imperative that demands a dynamic semantic treatment? (shrink)

This paper argues that the innovation of an ordering source parameter in the standard Lewis-Kratzer semantics for modals was a mistake, at least for English auxiliaries like ‘ought’, and that a simpler dyadic semantics (as proposed in my earlier work) provides a superior account of normative uses of modals. I programmatically investigate problems arising from (i) instrumental conditionals, (ii) gradability and “weak necessity”, (iii) information-sensitivity, and (iv) conflicts, and show how the simpler semantics provides intuitive solutions given three basic moves: (...) (1) an end-relational analysis of normative modality, (2) a “most” analysis of “weak necessity”, and (3) well-motivated appeals to pragmatics. I conclude with metasemantic observations about the desiderata for a semantics for ‘ought’. (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)

This is a study in the meaning of natural language probability operators, sentential operators such as probably and likely. We ask what sort of formal structure is required to model the logic and semantics of these operators. Along the way we investigate their deep connections to indicative conditionals and epistemic modals, probe their scalar structure, observe their sensitivity to contex- tually salient contrasts, and explore some of their scopal idiosyncrasies.

This paper develops a compositional, type-driven constraint semantic theory for a fragment of the language of subjective uncertainty. In the particular application explored here, the interpretation function of constraint semantics yields not propositions but constraints on credal states as the semantic values of declarative sentences. Constraints are richer than propositions in that constraints can straightforwardly represent assessments of the probability that the world is one way rather than another. The richness of constraints helps us model communicative acts in essentially the (...) same way that we model agents’ credences. Moreover, supplementing familiar truth-conditional theories of epistemic modals with constraint semantics helps capture contrasts between strong necessity and possibility modals, on the one hand, and weak necessity modals, on the other. (shrink)

Weak ontic necessity is the ontic necessity expressed by “should/ought to” in English. An example of it is “I should be dead by now”. A feature of this necessity is that whether it holds at the present world is irrelevant to whether its prejacent holds at the present world. In this paper, by combining premise semantics and update semantics for conditionals, we present a logical theory for conditional weak ontic necessity based on context update. A context is a set of (...) ordered defaults, determining expected possible states of the present world. Sentences are evaluated with respect to contexts. When evaluating the conditional weak ontic necessity with respect to a context, we first update the context with the antecedent, then check whether the consequent holds with respect to the updated context. We compare this theory to some related works. The logic’s expressivity is studied. (shrink)

Why can I not appropriately utter ‘It must be raining’ while standing outside in the rain, even though every world consistent with my knowledge is one in which it is raining? The common response to this problem is to hold that epistemic must, in addition to quantifying over epistemic possibilities, carries some additional evidential information concerning the source of one'S evidence. I argue that this is a mistake: epistemic modals are mere quantifiers over epistemic possibilities. My central claim is that (...) the seeming anomaly of the data above arises from a mistaken conception of what a possibility is. Instead of conceiving of possibilities as possible worlds, I argue that we should conceive of possibilities as answers to open questions. (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)

This paper argues that several leading theories of subjunctive conditionals are incompatible with ordinary intuitions about what credences we ought to have in subjunctive conditionals. In short, our theory of subjunctives should intuitively display semantic humility, i.e. our semantic theory should deliver the truth conditions of sentences without pronouncing on whether those conditions actually obtain. In addition to describing intuitions about subjunctive conditionals, I argue that we can derive these ordinary intuitions from justified premises, and I answer a possible worry (...) for my derivation by refuting a subjunctive triviality result modeled on (Lewis 1976). I conclude that the debate over the correct theory of subjunctive conditionals requires settling meta-philosophical questions about the relative value of various virtues of first-order theories of subjunctive conditionals. (shrink)

Weak ontic necessity is the ontic necessity expressed by “should” or “ought to”. An example of it is “I should be dead by now”. A feature of this necessity is that whether it holds is irrelevant to whether its underlying proposition holds. This necessity essentially involves time. This paper presents a logic for conditional weak ontic necessity in branching time. The logic’s language includes the next instant operator, the last instant operator, and the operator for conditional weak ontic necessity. Formulas (...) are evaluated at tuples consisting of a tree-based model, a context, a timeline, and an instant. A context is a set of ordered ontic laws determining expected timelines. When evaluating conditional weak ontic necessity, we first update the context with the antecedent, then check whether the consequent holds with respect to the updated context. We discuss some consequences of the formalization and compare it to some related work. We study the logic’s expressivity and axiomatize a special validity of it. (shrink)

Some legal philosophers regard the use of deontic language to describe the law as philosophically significant. Joseph Raz argues that it gives rise to ‘the problem of normativity of law’. He develops an account of what he calls ‘detached’ legal statements to resolve the problem. Unfortunately, Raz’s account is difficult to reconcile with the orthodox semantics of deontic language. The article offers a revised account of the distinction between committed and detached legal statements. It argues that deontic statements carry a (...) Gricean generalized conversational implicature to the effect that the rules in question reflect the speaker’s own commitments. Detached legal statements are made when this implicature is either explicitly cancelled or when the conversational context is sufficient to defeat the implicature. I conclude by offering some tentative reflections on the theoretical significance of deontic language in the law. (shrink)