John MacFarlane explores how we might make sense of the idea that truth is relative. He provides new, satisfying accounts of parts of our thought and talk that have resisted traditional methods of analysis, including what we mean when we talk about what is tasty, what we know, what will happen, what might be the case, and what we ought to do.

Focusing on cases which involve binding into epistemic modals with definite descriptions and quantifiers, I raise some new problems for standard approaches to all of these expressions. The difficulties are resolved in a semantic framework that is dynamic in character. I close with a new class of problems about de re readings within the scope of modals.

A dynamic semantics for epistemically modalized sentences is an attractive alternative to the orthodox view that our best theory of meaning ascribes to such sentences truth-conditions relative to what is known. This essay demonstrates that a dynamic theory about might and must offers elegant explanations of a range of puzzling observations about epistemic modals. The first part of the story offers a unifying treatment of disputes about epistemic modality and disputes about matters of fact while at the same time avoiding (...) the complexities of alternative theories. The second part of the story extends the basic framework to cover some complicated data about retraction and the interaction between epistemic modality and tense. A comparison between the suggestion made in this essay and current versions of the orthodoxy is provided. (shrink)

Epistemic modals are a prominent topic in the literature on natural language semantics, with wide-ranging implications for issues in philosophy of language and philosophical logic. Considerations about the role that epistemic "might" and "must" play in discourse and reasoning have led to the development of several important alternatives to classical possible worlds semantics for natural language modal expressions. This is an opinionated overview of what I take to be some of the most exciting issues and developments in the field.

This paper argues that a priori justification is, in principle, compatible with naturalism—if the a priori is understood in a way that is free of the inessential properties that, historically, have been associated with the concept. I argue that empirical indefeasibility is essential to the primary notion of the a priori ; however, the indefeasibility requirement should be interpreted in such a way that we can be fallibilist about apriori-justified claims. This fallibilist notion of the a priori accords with the (...) naturalist’s commitment to scientific methodology in that it allows for apriori-justified claims to be sensitive to further conceptual developments and the expansion of evidence. The fallibilist apriorist allows that an a priori claim is revisable in only a purely epistemic sense. This modal claim is weaker than what is required for a revisability thesis to establish empiricism, so fallibilist apriorism represents a distinct position. (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)

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)

Some prominent accounts of scientific evidence treat evidence as an unrelativized concept. But whether belief in a hypothesis is justified seems relative to the epistemic situation of the believer. The issue becomes yet more complicated in the context of group epistemic agents, for then one confronts the problem of relativizing to an epistemic situation that may include conflicting beliefs. As a step toward resolution of these difficulties, an ideal of justification is here proposed that incorporates both an unrelativized evidence requirement (...) and the requirement of the security of the evidence on which a conclusion from data is based. The latter requirement incorporates the consideration of epistemic modal statements. (shrink)

Mights plug gaps. If p lacks a truth-value, then ‘It might be that p’ should also lack truth-value. Yet epistemic hedges often turn an unassertible statement into an assertible one. The phenomenon is illustrated in detail for two kinds of statements that are frequently alleged to be counterexamples to the principle of bivalence: future contingents and statements that apply predicates to borderline cases. The paper concludes by exploring the prospects for generalizing this gap-plugging strategy.

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. (shrink)

This paper presents a general-purpose update semantics for expressions of subjective uncertainty in natural language. First, a set of desiderata are established for how expressions of subjective uncertainty should behave in dynamic, update-based semantic systems; then extant implementations of expressions of subjective uncertainty in such models are evaluated and found wanting; finally, a new update semantics is proposed. The desiderata at the heart of this paper center around the contention that expressions of subjective uncertainty express beliefs which are not persistent, (...) whereas propositions express beliefs that are persistent. I argue that if we make the move of treating updates in a dynamic semantics as Bayesian updates, i.e. as conditionalization, then expressions of subjective uncertainty will behave the way we want them to without altering the way propositions behave. (shrink)

The received view says that possibility is the dual of necessity: a proposition is (metaphysically, logically, epistemically etc.) possible iff it is not the case that its negation is (metaphysically, logically, epistemically etc., respectively) necessary. This reading is usually taken for granted by modal logicians and indeed seems plausible when dealing with logical or metaphysical possibility. But what about epistemic possibility? We argue that the dual definition of epistemic possibility in terms of epistemic necessity generates tension when reasoning about non-idealized (...) agents and is a problem of concern for most hyperintensional epistemic logics that alleviate the problem of logical omniscience. The tension is particularly evident when knowledge is taken as a primitive to define other epistemic concepts, such as justification and belief, as done in the knowledge-first tradition. We propose a non-dual interpretation of epistemic possibility, employing a hyperintensionality filter similar to the one that makes the corresponding epistemic necessity operator hyperintensional. We employ the proposed semantics to model Stalnaker's belief as epistemic possibility of knowledge and provide a sound and complete axiomatization for a hyperintensional version of his bimodal logic of knowledge and belief. (shrink)

My aim in this paper is to give a philosophical analysis of the relationship between contingently available technology and the knowledge that it makes possible. My concern is with what specific subjects can know in practice, given their particular conditions, especially available technology, rather than what can be known “in principle” by a hypothetical entity like Laplace’s Demon. The argument has two parts. In the first, I’ll construct a novel account of epistemic possibility that incorporates two pragmatic conditions: responsibility and (...) practicability. For example, whether subjects can gain knowledge depends in some circumstances on whether they have the capability of gathering relevant evidence. In turn, the possibility of undertaking such investigative activities depends in part on factors like ethical constraints, economical realities, and available technology. In the second part of the paper, I’ll introduce “technological possibility” to analyze the set of actions made possible by available technology. To help motivate the problem and later test my proposal, I’ll focus on a specific historical case, one of the earliest uses of digital electronic computers in a scientific investigation. I conclude that the epistemic possibility of gaining access to scientific knowledge about certain subjects depends (in some cases) on the technological possibility for making responsible investigations. (shrink)

According to the widely endorsed Knowledge Account of Assertion, the epistemic requirements on assertion are captured by the Knowledge Norm of Assertion, which requires speakers only to assert what they know. This paper proposes that in addition to the Knowledge Norm there is also an Epistemic Propositional Certainty Norm of Assertion, which enjoins speakers only to assert p if they believe that p on the basis of evidence which makes p an epistemic propositional certainty. The paper explains how this propositional (...) certainty norm accounts for a range of data related to the practice of assertion and defends the norm against general objections to certainty norms of assertion put forward by Duncan Pritchard, John Turri, and Timothy Williamson, by drawing on linguistic theories about epistemic modals and gradable predicate semantics. Together these considerations show that the prospects of a certainty account of assertion are much more promising than is usually assumed. (shrink)

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)

Within the linguistics literature it is often claimed that epistemic modality, unlike other kinds of modality, does not contribute to truth-conditional content. In this paper I challenge this view. I reanalyze a variety of arguments which have been used in support of the non-truth-conditional view and show that they can be handled on an alternative analysis of epistemic modality. # 2006 Elsevier B.V. All rights reserved.

This paper argues that just as full beliefs can constitute knowledge, so can properties of your credence distribution. The resulting notion of probabilistic knowledge helps us give a natural account of knowledge ascriptions embedding language of subjective uncertainty, and a simple diagnosis of probabilistic analogs of Gettier cases. Just like propositional knowledge, probabilistic knowledge is factive, safe, and sensitive. And it helps us build knowledge-based norms of action without accepting implausible semantic assumptions or endorsing the claim that knowledge is interest-relative.

Epistemic contradictions are now a well-known and often discussed phenomenon among those who study epistemic modals. These contradictions are expressed by sentences like ‘It is raining and it might not be raining’ whose oddness to the common ear demands an explanation. However, it has turned out to be a rather controversial enterprise to provide such an explanation in a sufficiently precise and general manner. According to pragmatic explanations, epistemic contradictions are semantically consistent but pragmatically defective. According to semantic explanations, one (...) should regard epistemic contradictions as plain semantic inconsistencies. Endorsing such a semantic solution is, however, tantamount to rejecting classical logic, which predicts the consistency of epistemic contradictions. After arguing that all existing solutions to this problem face as yet unmet challenges, I will present a new solution that adequately overcomes these challenges. I will propose to view epistemic contradictions as semantically consistent but epistemically defective sentences. The main thesis emerging will be that we need neither abandon the inference rules of classical logic nor the classical truth-conditional approach to semantics to deal adequately with epistemic contradictions. (shrink)

Mind &Language, Volume 35, Issue 1, Page 115-138, February 2020.

The relativist's central objection to contextualism is that it fails to account for the disagreement we perceive in discourse about "subjective" matters, such as whether stewed prunes are delicious. If we are to adjudicate between contextualism and relativism, then, we must first get clear about what it is for two people to disagree. This question turns out to be surprisingly difficult to answer. A partial answer is given here; although it is incomplete, it does help shape what the relativist must (...) say if she is to do better than the contextualist in securing genuine disagreement. (shrink)

At the center of the debate between contextualist versus relativist semantics for epistemic modal claims is an empirical question about when competent subjects judge epistemic modal disagreement to be present. John MacFarlane’s relativist claims that we judge there to be epistemic modal disagreement across the widest range of cases. We wish to dispute the robustness of his data with the results of two studies. Our primary conclusion is that the actual disagreement data is not consistent with relativist predictions, and so, (...) that the primary motivation for relativism disappears. Our study differs from a related study by Knobe and Yalcin :1–21, 2014) in that we focus directly on the question of genuine disagreement, as opposed to a question about truth or the appropriateness of retraction. Some of our findings agree with theirs about relativism. We uncover new lessons along the way, including that there are widespread situation effects of epistemic modal discourse; idiosyncratic features of the vignettes significantly influencing judgments about epistemic modal disagreement. We reflect with mixed feelings on the prospects for contextualism to accommodate our findings. (shrink)

If what is known need not be closed under logical consequence, then a distinction arises between something's being known to be the case (by a specific agent) and its following from something known (to that subject). When each of these notions is represented by a sentence operator, we get a bimodal logic in which to explore the relations between the two notions.

The argument from faultless disagreement employed by the relativist purports to show that contextualism falls short of explaining cases of faultless disagreement. The demonstration is intended to give credence to the relativist semantics of epistemic modality expressions. In this paper we present some cases showing that even though cases of faultless disagreement do reveal some intrinsic features of epistemic modality claims, they do not support the relativist semantics. The sophistication of faultless disagreement goes beyond what the relativist semantics can cope (...) with. We also advance an epistemologically oriented proposal to account for faultless disagreement. (shrink)

In this paper I will be arguing that there are cases in which a subject, S, should have known that p, even though, given her state of evidence at the time, she was in no position to know it. My argument for this result will involve making two claims. The uncontroversial claim is this: S should have known that p when another person has, or would have, legitimate expectations regarding S’s epistemic condition, the satisfaction of these expectations would require that (...) S knows that p, and S fails to know that p. The controversial claim is that these three conditions are sometimes jointly satisfied. I will spend the majority of my time defending the controversial claim. I will argue that there are two main sources of legitimate expectations regarding another’s epistemic condition: participation in a legitimate social practice ; and moral and epistemic expectations more generally . In developing my position on this score, I will have an opportunity to defend the doctrine that there are “practice-generated entitlements” to expect certain things, where it can happen that the satisfaction of these expectations requires another’s having certain pieces of knowledge; to contrast practice-generated entitlements to expect with epistemic reasons to believe; to defend the idea that moral and epistemic standards themselves can be taken to reflect legitimate expectations we have of each other; to compare the “should have known” phenomenon with a widely-discussed phenomenon in the ethics literature—that of culpable ignorance; and finally to suggest the bearing of the “should have known” phenomenon to epistemology itself. (shrink)

Philosophers have observed that metaphysical necessity appears to be a true or real or genuine form of necessity while epistemic necessity does not. Similarly, natural necessity appears genuine while deontic necessity does not. But what is it for a form of necessity to be genuine? I defend an account of genuine necessity in explanatory terms. The genuine forms of necessity, I argue, are those that provide what I call necessitarianexplanation. I discuss the relationship of necessitarian explanation to ground.

The notion of conceivability has traditionally been regarded as crucial to an account of modal knowledge. Despite its importance to modal epistemology, there is no received explication of conceivability. In recent discussions, some have attempted to explicate the notion in terms of epistemic possibility. There are, however, two notions of epistemic possibility, a more familiar one and a novel one. I argue that these two notions are independent of one another. Both are irrelevant to an account of modal knowledge on (...) the predominant view of modal reality. Only the novel notion is relevant and apt on the competing view of modal reality; but this latter view is problematic in light of compelling counterexamples. Insufficient care regarding the independent notions of epistemic possibility can lead to two problems: a gross problem of conflation and a more subtle problem of obscuring a crucial fact of modal epistemology. Either problem needlessly hampers efforts to develop an adequate account of modal knowledge. I conclude that the familiar notion of epistemic possibility should be eschewed in the context of modal epistemology. (shrink)

Concessive knowledge attributions (CKAs) are knowledge attributions of the form ‘S knows p, but it’s possible that q’, where q obviously entails not-p (Rysiew, Nous (Detroit, Mich.) 35:477–514, 2001). The significance of CKAs has been widely discussed recently. It’s agreed by all that CKAs are infelicitous, at least typically. But the agreement ends there. Different writers have invoked them in their defenses of all sorts of philosophical theses; to name just a few: contextualism, invariantism, fallibilism, infallibilism, and that the knowledge (...) rules for assertion and practical reasoning are false. In fact, there is a lot of confusion about CKAs and their significance. I try to clear some of this confusion up, as well as show what their significance is with respect to the debate between fallibilists and infallibilists about knowledge in particular. (shrink)

In this paper I argue for a doctrine I call ?infallibilism?, which I stipulate to mean that If S knows that p, then the epistemic probability of p for S is 1. Some fallibilists will claim that this doctrine should be rejected because it leads to scepticism. Though it's not obvious that infallibilism does lead to scepticism, I argue that we should be willing to accept it even if it does. Infallibilism should be preferred because it has greater explanatory power (...) than fallibilism. In particular, I argue that an infallibilist can easily explain why assertions of ?p, but possibly not-p? (where the ?possibly? is read as referring to epistemic possibility) is infelicitous in terms of the knowledge rule of assertion. But a fallibilist cannot. Furthermore, an infallibilist can explain the infelicity of utterances of ?p, but I don't know that p? and ?p might be true, but I'm not willing to say that for all I know, p is true?, and why when a speaker thinks p is epistemically possible for her, she will agree (if asked) that for all she knows, p is true. The simplest explanation of these facts entails infallibilism. Fallibilists have tried and failed to explain the infelicity of ?p, but I don't know that p?, but have not even attempted to explain the last two facts. I close by considering two facts that seem to pose a problem for infallibilism, and argue that they don't. (shrink)

Linguistic intervention in rational decision making is standardly captured in terms of information change. But the standard view gives us no way to model interventions involving expressions that only have an attentional effects on conversational contexts. How are expressions with non‐informational content – like epistemic modals – used to intervene in rational decision making? We show how to model rational decision change without information change: replace a standard conception of value (on which the value of a set of worlds reduces (...) to values of individual worlds in the set) with one on which the value of a set of worlds is determined by a selection function that picks out a generic member world. We discuss some upshots of this view for theorizing in philosophy and formal semantics. (shrink)

Standard theories of epistemic possibility analyze this relation in terms of knowledge, entailment, or probability. These theories are mistaken. Here, I present counterexamples to the standard theories and defend a new theory: that a proposition is epistemically possible on a body of evidence just in case that evidence supports that if the proposition were true, then the evidence might exist. In addition to avoiding the problems of the standard views, this new theory captures good reasoning about epistemic possibilities and matches (...) intuitive judgments in a wide range of cases, giving us good reason to accept it. (shrink)

Contextualism about ‘might’ says that the property that ‘might’ expresses varies from context to context. I argue against contextualism. I focus on problems that contextualism apparently has with attitude ascriptions in which ‘might’ appears in an embedded ‘that’-clause. I argue that contextualists can deal rather easily with many of these problems, but I also argue that serious difficulties remain with collective and quantified says-that ascriptions. Herman Cappelen and John Hawthorne atempt to deal with these remaining problems, but I argue that (...) their attempt fails. (shrink)

This paper concerns a puzzle about the interaction of epistemic modals and future tense. In cases of predictable forgetfulness, speakers cannot describe their future states of mind with epistemic modals under future tense, but promising theories of epistemic modals do not predict this. In §1, I outline the puzzle. In §2, I argue that it undermines a very general approach to epistemic modals that draws a tight connection between epistemic modality and evidence. In §3, I defend the assumption that tense (...) can indeed scope over epistemic modals. In §4, I outline a new way of determining the domain of quantification of epistemic modals: epistemic modals quantify over the worlds compatible with the information accumulated within a certain interval. Information loss can change which interval is relevant for determining the domain. In §5, I defend the view from some objections. In §6, I explore the connections between my view of epistemic modality and circumstantial modality. (shrink)

In this paper, I consider a variant of the ancient Idle Argument involving so‐called “unconditionals” with interrogative antecedents. This new Idle Argument provides an ideal setting for probing the logic of these close relatives of if‐conditionals, which has been comparatively underexplored. In the course of refuting the argument, I argue that contrary to received wisdom, many unconditionals do not entail their main clauses, yet modus ponens is still unrestrictedly valid for this class of expressions. I make these lessons precise in (...) a formal system drawing on recent work in inquisitive semantics. My larger aim is to challenge standard truth preservation accounts of logic and deductive argumentation. (shrink)

According to a popular closure principle for epistemic justification, if one is justified in believing each of the premises in set Φ and one comes to believe that ψ on the basis of competently deducing ψ from Φ—while retaining justified beliefs in the premises—then one is justified in believing that ψ. This principle is prima facie compelling; it seems to capture the sense in which competent deduction is an epistemically secure means to extend belief. However, even the single-premise version of (...) this closure principle is in conflict with certain seemingly good inferences involving the epistemic possibility modal ♢. According to other compelling principles concerning competent deduction and epistemic justification, one can competently infer ¬♢φ from ¬φ in deliberation even though there are cases in which one can justifiably believe ¬φ but would be unjustified in believing ¬♢φ. Thus, as we argue, philosophers must choose between unrestricted closure for justification and the validity of these other principles. (shrink)

Habilitation thesis in psychology. The book consists of a collection of reasoning studies. The experimental investigations will take us from people’s reasoning about probabilities, entailments, pragmatic factors, argumentation, and causality to morality. An overarching theme of the book is norm pluralism and individual differences in rationality research.

Statements containing epistemic modals (e.g., “by spring 2023 most European countries may have the Covid-19 pandemic under control”) are common expressions of epistemic uncertainty. In this paper, previous published findings (Knobe & Yalcin, 2014; Khoo & Phillips, 2018) on the opposition between Contextualism and Relativism for epistemic modals are re-examined. It is found that these findings contain a substantial degree of individual variation. To investigate whether participants differ in their interpretation of epistemic modals, an experiment with multiple phases and sessions (...) is used to classify participants according to the three semantic theories of Relativism, Contextualism, and Objectivism. Through this study, some of the first empirical evidence for the kind of truth-value shifts postulated by semantic Relativism is presented. It is furthermore found that participants’ disagreement judgments match their truth evaluations and that participants are capable of distinguishing between truth and justification. In a second experimental session, it is investigated whether participants thus classified follow the norm of retraction which Relativism uses to account for argumentation with epistemic modals. Here the results are less favorable for Relativism. In a second experiment, these results are replicated and the normative beliefs of participants concerning the norm of retraction are investigated following work on measuring norms by Bicchieri (2017). Again, it is found that on average participants show no strong preferences concerning the norm of retraction for epistemic modals. Yet, it was found that participants who had committed to Objectivism and had training in logics applied the norm of retraction to might-statements. These results present a substantial challenge to the account of argumentation with epistemic modals presented in MacFarlane (2014), as discussed. Keywords: Epistemic Modals, Relativism, Norm Conflicts, Retraction, Semantics, Truth Conditions, Argumentation. (shrink)

Situation semantics was developed as an alternative to possible worlds semantics. In situation semantics, linguistic expressions are evaluated with respect to partial, rather than complete, worlds. There is no consensus about what situations are, just as there is no consensus about what possible worlds or events are. According to some, situations are structured entities consisting of relations and individuals standing in those relations. According to others, situations are particulars. In spite of unresolved foundational issues, the partiality provided by situation semantics (...) has led to some genuinely new approaches to a variety of phenomena in natural language semantics. In the way of illustration, this article includes relatively detailed overviews of a few selected areas where situation semantics has been successful: implicit quantifier domain restrictions, donkey pronouns, and exhaustive interpretations. It moreover addresses the question of how Davidsonian event semantics can be embedded in a semantics based on situations. Other areas where a situation semantics perspective has led to progress include attitude ascriptions, questions, tense, aspect, nominalizations, implicit arguments, point of view, counterfactual conditionals, and discourse relations. (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..

My dissertation asks how we affect conversational context and how it affects us when we participate in any conversation—including philosophical conversations. Chapter 1 argues that speakers make pragmatic presuppositions when they use proper names. I appeal to these presuppositions in giving a treatment of Frege’s puzzle that is consistent with the claim that coreferential proper names have the same semantic value. I outline an explanation of the way presupposition carrying expressions in general behave in belief ascriptions, and suggest that substitutivity (...) failure is a special case of this behavior. Chapter 2 develops a compositional probabilistic semantics for the language of subjective uncertainty, including epistemic adjectives scoped under quantifiers. I argue that we should distinguish sharply between the effects that epistemically hedged statements have on conversational context, and the effects that they have on belief states. I also suggest that epistemically hedged statements are a kind of doxastic advice, and explain how this hypothesis illuminates some otherwise puzzling phenomena. Chapter 3 argues that ordinary causal talk is deeply sensitive to conversational context. The principle that I formulate to characterize that context sensitivity explains at least some of the oddness of ‘systematic causal overdetermination,’ and explains why some putative overgenerated causes are never felicitously counted, in conversation, as causes. But the principle also makes metaphysical theorizing about causation rather indirectly constrained by ordinary language judgments. (shrink)

The subject of this paper is the epistemology of identity: a general theory of knowledge, evidence and justification for the claim that one thing is identical to another. Although identity figures significantly in our epistemic lives, this is a topic that, to the best of my knowledge, has gone entirely unexplored. Initial attempts to integrate such an epistemology into existing theories of evidence---many of which are tailor-made for contingent propositions---are confounded by the necessity of identity. I defend a restricted form (...) of skepticism according to which the only knowable identity claims are trivial. (shrink)

There is an account of modal operators that is both elegant and powerful and that deserves to be called the standard account. There are, however, some epistemic uses of modal operators which seem to be counterexamples to the account – they pose what I call the objectivity problem. It is often thought that the objectivity problem can be fixed by a certain kind of modification to the standard account. I argue that this kind of modification cannot work. Then I argue (...) that the problem posed for the standard account by recently discussed eavesdropper cases is really just the objectivity problem in a different guise, thereby emphasizing the need for a new solution to the objectivity problem. Finally, I propose a new solution to the objectivity problem. (shrink)

There is a lot that we don’t know. That means that there are a lot of possibilities that are, epistemically speaking, open. For instance, we don’t know whether it rained in Seattle yesterday. So, for us at least, there is an epistemic possibility where it rained in Seattle yesterday, and one where it did not. It’s tempting to give a very simple analysis of epistemic possibility: • A possibility is an epistemic possibility if we do not know that it does (...) not obtain. But this is problematic for a few reasons. One issue, one that we’ll come back to, concerns the first two words. The analysis appears to quantify over possibilities. But what are they? As we said, that will become a large issue pretty soon, so let’s set it aside for now. A more immediate problem is that it isn’t clear what it is to have de re attitudes towards possibilities, such that we know a particular possibility does or doesn’t obtain. Let’s try rephrasing our analysis so that it avoids this complication. (shrink)

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..