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)

Faultless disagreement and faultless retraction have been taken to motivate relativism for predicates of personal taste, like ‘tasty’. Less attention has been devoted to the question of what aspect of their meaning underlies this relativist behavior. This paper illustrates these same phenomena with a new category of expressions: appearance predicates, like ‘tastes vegan’ and ‘looks blue’. Appearance predicates and predicates of personal taste both fall into the broader category of experiential predicates. Approaching predicates of personal taste from this angle suggests (...) that their relativist behavior is due to their experience-sensitivity, rather than their evaluative meaning. Furthermore, appearance predicates hold interest beyond what they can teach us about predicates of personal taste. Examination of a variety of uses of appearance predicates reveals that they give rise to relativist behavior for a variety of reasons—including some that apply also to other types of expressions, such as epistemic modals and comparative terms. This paper thus serves both to probe the source of relativist behavior in discourse about personal taste, as well as to map out this kind of behavior in the rich and under-explored discourse about appearances. (shrink)

Much linguistic evidence supports the view believing something only requires thinking it likely. I assess and reject a rival view, based on recent work on homogeneity in natural language, according to which belief is a strong, demanding attitude. I discuss the implications of the linguistic considerations about ‘believe’ for our philosophical accounts of belief.

We distinguish three ways that a theory of linguistic meaning and communication might be considered dynamic in character. We provide some examples of systems which are dynamic in some of these senses but not others. We suggest that separating these notions can help to clarify what is at issue in particular debates about dynamic versus static approaches within natural language semantics and pragmatics.

There is a longstanding debate in the literature about static versus dynamic approaches to meaning and conversation. A formal result due to van Benthem is often thought to be important for understanding what, conceptually speaking, is at issue in the debate. We introduce the concept of a conversation system, and we use it to clarify the import of van Benthem's result. We then distinguish two classes of conversation systems, corresponding to two concepts of staticness. The first class corresponds to a (...) generalization of the class of systems that van Benthem's result concerns. These are the strongly static conversation systems. The second class is broader, and allows for a certain commonly recognized form of context sensitivity. These are the weakly static conversation systems. In the vein of van Benthem's result, we supply representation theorems which independently characterize these two varieties of conversation system. We observe that some canonically dynamic semantic systems correspond to weakly static conversation systems. We close by discussing some hazards that arise in trying to bring our formal results to bear on natural language phenomena, and on the debate about whether the compositional semantics for natural language should take a dynamic shape. (shrink)

Barristers in England are obliged to follow the ‘cab rank rule’, according to which they must take any case offered to them, as long as they have time in their.

After presenting a simple expressivist account of reports of probabilistic judgements, I explore a classic problem for it, namely the Frege-Geach problem. I argue that it is a problem not just for expressivism but for any reasonable account of ascriptions of graded judgements. I suggest that the problem can be resolved by appropriately modelling imprecise credences.

Discusses how to capture the link between the probability of indicative conditionals and conditional probability using a classical semantics for conditionals.

IntroductionThe project of giving an account of meaning in natural languages goes largely by assigning truth-conditional content to sentences. I will call the view that sentences have truth-conditional content propositionalism as it is common to identify the truth-conditional content of a sentence with the proposition it expresses. This content plays an important role in our explanations of the speech-acts, attitude ascriptions, and the meaning of sentences when they appear as parts of longer sentences. Much work in philosophy of language and (...) linguistics semantics over the last half-century has aimed to characterize the truth-conditional content of different aspects of language.There are different kinds of worries one might have about this project. There are general methodological worries about truth-conditional semantics that have had some currency in the philosophical literature. In my view, the enormous progress in semantics made in its brief history suggests these are misplaced. Ho .. (shrink)

The phenomenon of disagreement has recently been brought into focus by the debate between contextualists and relativist invariantists about epistemic expressions such as ‘might’, ‘probably’, indicative conditionals, and the deontic ‘ought’. Against the orthodox contextualist view, it has been argued that an invariantist account can better explain apparent disagreements across contexts by appeal to the incompatibility of the propositions expressed in those contexts. This paper introduces an important and underappreciated phenomenon associated with epistemic expressions — a phenomenon that we call (...) reversibility. We argue that the invariantist account of disagreement is incompatible with reversibility, and we go on to show that reversible sentences cast doubt on the putative data about disagreement, even without assuming invariantism. Our argument therefore undermines much of the motivation for invariantism, and provides a new source for constraints on the proper explanation of purported data about disagreement. (shrink)

We assume a central thesis about modal auxiliaries due to Angelika Kratzer, the modal base presupposition: natural language expressions that contain a modal component in their meaning, including all English modal auxiliaries and epistemic modal auxiliaries (EMA)s in particular, presuppose a modal base, a function that draws from context a relevant set of propositions which contribute to a premise-semantics for the modal. Accepting this thesis for EMAs leaves open (at least) the following two questions about the meaning of English EMAs (...) like _must_ and _might_: (i) What constraints, if any, are there on the character of the premise set for an EMA? And (ii) what is the nature of the relationship between premises and conclusion that is required for truth of the EMA statement? I argue for at least a partial answer to (i), with a hypothesis about constraints on the modal base for an EMA: EMAs, unlike some other types of modals, are indexical: They are anchored to an agent-in-a-situation whose doxastic state is currently under discussion in the context of utterance. Realized in a Kratzerian semantics, indexicality sheds new light on a number of outstanding puzzles, including the widely observed variability of anchoring of EMAs, the ways in which EMAs differ from so-called root modals, Yalcin’s (Mind 116:983–1026, 2007) puzzle (a version of Moore’s paradox for epistemic modals embedded under attitudes), how to explain the apparent weakness of necessity EMAs, and problems with second order belief and disagreement. (shrink)

The purpose of this paper is to defend a conception of language that does not rely on linguistic meanings, and use it to address the Sorites and Liar paradoxes.

This essay investigates whether or not we should think that the things we say are identical to the things our sentences mean. It is argued that these theoretical notions should be distinguished, since assertoric content does not respect the compositionality principle. As a paradigmatic example, Kaplan's formal language LD is shown to exemplify a failure of compositionality. It is demonstrated that by respecting the theoretical distinction between the objects of assertion and compositional values certain conflicts between compositionality and contextualism are (...) avoided. This includes the conflict between eternalism and the semantics of tense, the embedding problems for contextualism about epistemic modals and taste claims, and the conflict between direct reference and the semantics of bound pronouns (and monstrous operators). After presenting the theoretical picture which distinguishes assertoric content from compositional semantic value, some objections to the picture are addressed. In so doing, the objection from King (2003) stemming from apparent complications with the interaction of temporal expressions and attitude reports is assessed and shown to be non-threatening. (shrink)

A conversation can be conceived as aiming to circumscribe a set of possibilities that are relevant to the goals of the conversation. This set of possibilities may be conceived as determined by the goals and objective circumstances of the interlocutors and not by their propositional attitudes. An indicative conditional can be conceived as circumscribing a set of possibilities that have a certain property: If the set of relevant possibilities is subsequently restricted to one in which the antecedent holds, then it (...) will be restricted as well to one in which the consequent holds. We will identify a number of desiderata concerning the validity of arguments; we will develop a formally precise semantics for conditionals conceived in this way that satisfies the desiderata, and we will present a deductive calculus that is sound and complete with respect to the semantics. Finally, we will argue that the semantics compares well, both formally and foundationally, with two other semantic theories of indicative conditionals that satisfy the desiderata, namely, those of Gillies and Bledin. (shrink)

An area in the theory of action that has received little attention is how mental agency and world-directed agency interact. The purpose of the present contribution is to clarify the rational conditions of such interaction, through an analysis of the central case of acceptance. There are several problems with the literature about acceptance. First, it remains unclear how a context of acceptance is to be construed. Second, the possibility of conjoining, in acceptance, an epistemic component, which is essentially mind-to-world, and (...) a utility component, which requires a world-to-mind direction of fit, is merely posited rather than derived from the rational structure of acceptance. Finally, the norm of acceptance is generally seen as related to truth, which turns out to be inapplicable in a number of cases. We will argue, first, that the specific context-dependence of acceptances is derived from their being mental actions, each embedded in a complex hierarchy of acceptances composing, together, a planning sequence. Second, that acceptances come in several varieties, corresponding to the specific epistemic norm(s) that constitute them. The selection of a particular norm for accepting answers to considerations of utility – to the association of an epistemic goal with an encompassing world-directed action. Once a type of acceptance is selected, however, the epistemic norm constitutive for that acceptance strictly applies. Third, we argue that context-dependence superimposes a decision criterion on the output of the initial epistemic acceptance. Strategic acceptance is regulated by instrumental norms of expected utility, which may rationally lead an agent to screen off her initial epistemic acceptance. (shrink)

The 3sg pronouns “he” and “she” impose descriptive gender conditions on their referents. These conditions are standardly analysed as presuppositions. Cooper argues that, when 3sg pronouns occur free, they have indexical presuppositions: the gender condition must be satisfied by the pronoun’s referent in the actual world. In this paper, we consider the behaviour of free 3sg pronouns in conditionals and focus on cases in which the pronouns’ gender presuppositions no longer seem to be indexical and project locally instead. We compare (...) these cases to previously reported shifty readings of indexicals in so-called “epistemic conditionals” :359–406, 2012) and propose a unified account of locally projected gender presuppositions and shifty indexicals based on the idea that indicative conditionals are Kaplanian monsters. (shrink)

I argue that if there are nondisabled reasons to believe p, then there cannot be nondisabled reasons to believe something incompatible with p. I first defend a restricted version of the view, which applies only to situations where the relevant agent has complete evidence. Then, I argue for a generalized version of the view, which holds regardless of the agent's evidence. As a related result, I show that, given plausible assumptions, there cannot be nondisabled reasons to believe something false.

I argue that if there are nondisabled reasons to believe p, then there cannot be nondisabled reasons to believe something incompatible with p. I first defend a restricted version of the view, which applies only to situations where the relevant agent has complete evidence. Then, I argue for a generalized version of the view, which holds regardless of the agent's evidence. As a related result, I show that, given plausible assumptions, there cannot be nondisabled reasons to believe something false.

Is there anything wrong with publishing philosophical work which one does not believe (publishing without belief, henceforth referred to as ‘PWB’)? I argue that there is not: the practice isn’t intrinsically wrong, nor is there a compelling consequentialist argument against it. Therefore, the philosophical community should neither proscribe nor sanction it. The paper proceeds as follows. First, I’ll clarify and motivate the problem, using both hypothetical examples and a recent real-world case. Next, I’ll look at arguments that there is something (...) wrong with PWB, and show that none is sound. Then, I’ll give some reasons for thinking a norm against PWB is detrimental to the profession. Do I believe these arguments? If I’m right, it shouldn’t matter. (shrink)

A series of recent studies have explored the impact of people's judgments regarding physical law, morality, and probability. Surprisingly, such studies indicate that these three apparently unrelated types of judgments often have precisely the same impact. We argue that these findings provide evidence for a more general hypothesis about the kind of cognition people use to think about possibilities. Specifically, we suggest that this aspect of people's cognition is best understood using an idea developed within work in the formal semantics (...) tradition, namely the notion of modality. On the view we propose, people may have separate representations for physical, moral and probabilistic considerations, but they also integrate these various considerations into a unified representation of modality. (shrink)

Hybrid metaethical theories have significant promise; they would have important upshots if they were true. But they also face severe problems. The problems are severe enough to make many philosophers doubt that they could be true. My ambition is to show that the problems are just instances of a highly general problem: a problem about what are sometimes called ‘intensional anaphora'. I'll also show that any adequate explanation of intensional anaphora immediately solves all the problems for the hybrid theorist. We (...) should regard hybrid tools as among the most legitimate tools in our toolkit—at least when we use them properly. (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)

Frege's puzzle about identity sentences has long challenged many philosophers to find a solution to it but also led other philosophers to object that the evidential datum it is grounded on is false. The present work is an elaboration of this second kind of reaction: it explains why Frege's puzzle seems to resist the traditional objection, giving voice to different and more elaborated presentations of the evidential datum, faithful to the spirit but not to the letter of Frege's puzzle. The (...) final outcome is negative, no satisfactory formulation of the evidential datum is found and Frege's puzzle is challenged until a better formulation of it is found. (shrink)

How does your information change when you learn that something might be the case, where the modal “might” is epistemic? On the orthodox view, a proposition is added to your information base; on the view defended here, no propositions are added to your information base but some are removed from it. I argue that Stephen Yablo’s recent attempt to define this removal operation as a kind of propositional subtraction fails, offer a definition of my own in terms of the part–whole (...) relations between the truthmakers of the propositions one accepts, and argue that a deontic analogue of this account solves a problem about permission posed long ago by David Lewis. (shrink)

Recently, philosophers have offered compelling reasons to think that demonstratives are best represented as variables, sensitive not to the context of utterance, but to a variable assignment. Variablists typically explain familiar intuitions about demonstratives—intuitions that suggest that what is said by way of a demonstrative sentence varies systematically over contexts—by claiming that contexts initialize a particular assignment of values to variables. I argue that we do not need to link context and the assignment parameter in this way, and that we (...) would do better not to. (shrink)

I give a semantics for a logic with two pairs of doxastic modals and an indicative conditional connective that all nest without restriction. Sentences are evaluated as accepted, rejected, or neither. Certainty is the necessity-like modality of acceptance. Inferences may proceed from premises that are certain, or merely accepted, or a mix of both. This semantic setup yields some striking results. Notably, the existence of inferences that preserve certainty but not acceptance very directly implies both failure of modus ponens for (...) the indicative conditional in the logic of acceptance and failure of the deduction theorem for the material conditional in the logic of certainty. The latter failure dissolves, in the logic of certainty, the much - discussed tension between modus ponens and the law of import-export. (shrink)

This essay introduces a puzzle about the interaction between quantifiers and epistemic modals. The puzzle motivates the idea that whether an object satisfies an epistemically modalized predicate depends on the mode of presentation of the domain of quantification. I compare two ways of implementing this idea, one using counterpart theory, the other using Aloni's 'conceptual covers' theory, and then provides some evidence in favor of the former.

The standard account of modal expressions in natural language analyzes them as quantifiers over a set of possible worlds determined by the evaluation world and an accessibility relation. A number of authors have recently argued for an alternative account according to which modals are analyzed as quantifying over a domain of possible worlds that is specified directly in the points of evaluation. But the new approach only handles the data motivating it if it is supplemented with a non-standard account of (...) attitude verbs and conditionals. It can be shown the the relational account handles the same data equally well if it too is supplemented with a non-standard account of such expressions. (shrink)

This paper is about the relationship between two questions: the question of what the objects of assertion are and the question of how best to theorise about ‘shifty’ phenomena like modality and tense. I argue that the relationship between these two questions is less direct than is often supposed. I then explore the consequences of this for a number of debates in the philosophy of language.

Kripke (1980) hypothesizes a link between rigidity and scope: a singular term is rigid over a space S of possibilities just in case it is scopeless with respect to modals that quantify over S. Kripke’s hypothesis works well when we consider the interaction of singular terms with metaphysical modals, but runs into trouble when we consider the interaction of singular terms with epistemic modals. After describing the trouble in detail, and considering one non-solution to it, I develop a novel version (...) of dynamic semantics that resolves the problem. (shrink)

Chancy modus ponens is the following inference scheme: ‘probably φ’, ‘if φ, then ψ’, therefore, ‘probably ψ’. I argue that Chancy modus ponens is invalid in general. I further argue that the invalidity of Chancy modus ponens sheds new light on the alleged counterexample to modus ponens presented by McGee. I close by observing that, although Chancy modus ponens is invalid in general, we can recover a restricted sense in which this scheme of inference is valid.

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)

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)

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.

I present a puzzle about belief and credence, which takes the form of three independently supported views that are mutually inconsistent. The first is the view that S has a modal belief that p (e.g., S believes that probably-p) if and only if S has a corresponding credence that p. The second is the view that S believes that p only if S has some credence that p. The third is the view that, possibly, S believes that p without a (...) modal belief that p. [Word Count: 85]. (shrink)

I defend a contextualist account of bare epistemic modal claims against recent objections. I argue that in uttering a sentence of the form ‘It might be that p,’ a speaker is performing two speech acts. First, she is (directly) asserting that in view of the knowledge possessed by some relevant group, it might be that p. The content of this first speech act is accounted for by the contextualist view. But the speaker's utterance also generates an indirect speech act that (...) consists in a weak suggestive that p. Since this second speech act is typically the main point of a bare epistemic modal utterance, our (negative or positive) responses to the utterance actually target this second speech act. I show how this two-speech-act account can explain the data recently adduced against contextualism. (shrink)

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)

Recent years have witnessed a proliferation of attempts to apply the mathematical theory of probability to the semantics of natural language probability talk. These sorts of “probabilistic” semantics are often motivated by their ability to explain intuitions about inferences involving “likely” and “probably”—intuitions that Angelika Kratzer’s canonical semantics fails to accommodate through a semantics based solely on an ordering of worlds and a qualitative ranking of propositions. However, recent work by Wesley Holliday and Thomas Icard has been widely thought to (...) undercut this motivation: they present a world-ordering semantics that yields essentially the same logic as probabilistic semantics. In this paper, I argue that the challenge remains: defenders of world-ordering semantics have yet to offer a plausible semantics that captures the logic of comparative likelihood. Holliday & Icard’s semantics yields an adequate logic only if models are restricted to Noetherian pre-orders. But I argue that the Noetherian restriction faces problems in cases involving infinitely large domains of epistemic possibilities. As a result, probabilistic semantics remains the better explanation of the data. (shrink)

There is a difference between the conditions in which one can felicitously use a ‘must’-claim like and those in which one can use the corresponding claim without the ‘must’, as in 'It must be raining out' versus 'It is raining out. It is difficult to pin down just what this difference amounts to. And it is difficult to account for this difference, since assertions of 'Must p' and assertions of p alone seem to have the same basic goal: namely, communicating (...) that p is true. In this paper I give a new account of the conversational role of ‘must’. I begin by arguing that a ‘must’-claim is felicitous only if there is a shared argument for the proposition it embeds. I then argue that this generalization, which I call Support, can explain the more familiar generalization that ‘must’-claims are felicitous only if the speaker’s evidence for them is in some sense indirect. Finally, I propose a pragmatic derivation of Support as a manner implicature. (shrink)

I explore the logic of the conditional, using credence judgments to argue against Duality and in favor of Conditional Excluded Middle. I then explore how to give a theory of the conditional which validates the latter and not the former, developing a variant on Kratzer (1981)'s restrictor theory, as well as a proposal which combines Stalnaker (1968)'s theory of the conditional with the theory of epistemic modals I develop in Mandelkern 2019a. I argue that the latter approach fits naturally with (...) a conception of conditionals as referential devices which allow us to talk about particular worlds. (shrink)

We show that each of three natural sets of assumptions about the conditional entails necessitarianism: that anything possible is necessary.

I discuss what I call practical Moore sentences: sentences like ‘You must close your door, but I don’t know whether you will’, which combine an order together with an avowal of agnosticism about whether the order will be obeyed. I show that practical Moore sentences are generally infelicitous. But this infelicity is surprising: it seems like there should be nothing wrong with giving someone an order while acknowledging that you do not know whether it will obeyed. I suggest that this (...) infelicity points to a striking psychological fact, with potentially broad ramifications concerning the structure of norms of speech acts: namely, when giving an order, we must act as if we believe we will be obeyed. (shrink)

When embedding data are used to argue against semantic theory A and in favor of semantic theory B, it is important to ask whether A could make sense of those data. It is possible to ask that question on a case-by-case basis. But suppose we could show that A can make sense of all the embedding data which B can possibly make sense of. This would, on the one hand, undermine arguments in favor of B over A on the basis (...) of embedding data. And, provided that the converse does not hold—that is, that A can make sense of strictly more embedding data than B can—it would also show that there is a precise sense in which B is more constrained than A, yielding a pro tanto simplicity-based consideration in favor of B. In this paper I develop tools which allow us to make comparisons of this kind, which I call comparisons of potential expressive power. I motivate the development of these tools by way of exploration of the recent debate about epistemic modals. Prominent theories which have been developed in response to embedding data turn out to be strictly less expressive than the standard relational theory, a fact which necessitates a reorientation in how to think about the choice between these theories. (shrink)

The Identity principle says that conditionals with the form 'If p, then p' are logical truths. Identity is overwhelmingly plausible, and has rarely been explicitly challenged. But a wide range of conditionals nonetheless invalidate it. I explain the problem, and argue that the culprit is the principle known as Import-Export, which we must thus reject. I then explore how we can reject Import-Export in a way that still makes sense of the intuitions that support it, arguing that the differences between (...) indicative and subjunctive conditionals play a key role in solving this puzzle. (shrink)

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

I show that standard dynamic approaches to the semantics of epistemic modals invalidate the classical laws of excluded middle and non-contradiction, as well as the law of epistemic non-contradiction. I argue that these facts pose a serious challenge.

What does 'might' mean? One hypothesis is that 'It might be raining' is essentially an avowal of ignorance like 'For all I know, it's raining'. But it turns out these two constructions embed in different ways, in particular as parts of larger constructions like Wittgenstein's 'It might be raining and it's not' and Moore's 'It's raining and I don't know it', respectively. A variety of approaches have been developed to account for those differences. All approaches agree that both Moore sentences (...) and Wittgenstein sentences are classically consistent. In this paper I argue against this consensus. I adduce a variety of new data which I argue can best be accounted for if we treat Wittgenstein sentences as being classically inconsistent. This creates a puzzle, since there is decisive reason to think that 'Might p' is classically consistent with 'Not p'. How can it also be that 'Might p and not p' and 'Not p and might p' are classically inconsistent? To make sense of this situation, I propose a new theory of epistemic modals and their interaction with embedding operators. This account makes sense of the subtle embedding behavior of epistemic modals, shedding new light on their meaning and, more broadly, the dynamics of information in natural language. -/- . (shrink)

McGee argued that modus ponens was invalid for the natural language conditional ‘If…then…’. Many subsequent responses have argued that, while McGee’s examples show that modus ponens fails to preserve truth, they do not show that modus ponens fails to preserve rational full acceptance, and thus modus ponens may still be valid in the latter informational sense. I show that when we turn our attention from indicative conditionals to subjunctive conditionals, we find that modus ponens does not preserve either truth or (...) rational full acceptance, and thus is not valid in either sense. In concluding I briefly consider how we can account for these facts. (shrink)