Epistemic possibilities are relative to bodies of information, or perspectives. To claim that something is epistemically possible is typically to claim that it is possible relative one’s own current perspective. We generally do this by using bare, unqualified epistemic possibility (EP) sentences, ones that don’t mention our perspective. The fact that epistemic possibilities are relative to perspectives suggests that these bare EP sentences fall short of fully expressing propositions, contrary to what both contextualists and relativists take for granted. Although they (...) rightly reject propositional invariantism, the implausible view that a bare EP sentence expresses the same classical (absolutely true or absolutely false) proposition in any context, they maintain that a change in perspective shifts either the sentence’s propositional content (to a proposition involving a different perspective) or its truth-value (the same perspectivally neutral proposition now evaluated from a different perspective). I deny that the semantic contents of bare EP sentences shift at all. But I also deny that these contents have truth-values. Rather, according to the radical invariantism I defend, these contents are not full-fledged propositions but merely propositional radicals. Only explicitly relativized EP sentences manage fully to express propositions, and these perspective-involving propositions are the only EP propositions there are. Nevertheless, bare EP sentences are perfectly capable of being used to assert EP propositions, because utterances of them implicitly allude to the relevant perspective. Various problem cases challenge radical invariantism to explain pragmatically which perspective is read into the utterance of a given bare EP sentence. Unlike contextualism and relativism, it can do this without having to resort to any semantic bells and whistles.. (shrink)

On one view about the word ‘might’, to say, sincerely and literally, that it might be that S is to say something about one’s epistemic state (and perhaps also about the epistemic states of those around one). For convenience, I will call this the natural view about ‘might’ . On one version of the natural view, to say that it might be that S is to say that what one is certain of is consistent with the proposition that S . (...) Seth Yalcin ( 2007 ) has argued that all versions of the natural view are wrong. My aim in this article is to show how at least one version of the natural view escapes Yalcin’s argument. (shrink)

Michael Huemer (2007) has articulated a provocative account of the concept of "epistemic possibility" which he hopes will explicate the explanatory value of the concept while also lending support to a broader anti-skeptical strategy. While I think his account has a number of advantages, many of which Huemer himself identifies, there are also significant disadvantages which should prompt us to seek an alternative. In this paper I describe an alternative which builds on some of the better features of Huemer's account, (...) while avoiding its shortcomings. After having explained why this alternative avoids the problems I attribute to Huemer's position, I will conclude by presenting some independent considerations in favor of my account, which recommends that epistemic possibility claims be subjected to the same evidentialist standards to which belief and assertion are usually held accountable. (shrink)

The paper begins with a clarification of the notions of intuition (and, in particular, modal intuition), modal error, conceivability, metaphysical possibility, and epistemic possibility. It is argued that two-dimensionalism is the wrong framework for modal epistemology and that a certain nonreductionist approach to the theory of concepts and propositions is required instead. Finally, there is an examination of moderate rationalism.

In this paper, I investigate whether we can use a world-involving framework to model the epistemic states of non-ideal agents. The standard possible-world framework falters in this respect because of a commitment to logical omniscience. A familiar attempt to overcome this problem centers around the use of impossible worlds where the truths of logic can be false. As we shall see, if we admit impossible worlds where “anything goes” in modal space, it is easy to model extremely non-ideal agents that (...) are incapable of performing even the most elementary logical deductions. A much harder, and considerably less investigated challenge is to ensure that the resulting modal space can also be used to model moderately ideal agents that are not logically omniscient but nevertheless logically competent. Intuitively, while such agents may fail to rule out subtly impossible worlds that verify complex logical falsehoods, they are nevertheless able to rule out blatantly impossible worlds that verify obvious logical falsehoods. To model moderately ideal agents, I argue, the job is to construct a modal space that contains only possible and non-trivially impossible worlds where it is not the case that “anything goes”. But I prove that it is impossible to develop an impossible-world framework that can do this job and that satisfies certain standard conditions. Effectively, I show that attempts to model moderately ideal agents in a world-involving framework collapse to modeling either logical omniscient agents, or extremely non-ideal agents. (shrink)

When a proposition might be the case, for all an agent knows, we can say that the proposition is epistemically possible for the agent. In the standard possible worlds framework, we analyze modal claims using quantification over possible worlds. It is natural to expect that something similar can be done for modal claims involving epistemic possibility. The main aim of this paper is to investigate the prospects of constructing a space of worlds—epistemic space—that allows us to model what is epistemically (...) possible for ordinary, non-ideally rational agents like you and me. I will argue that the prospects look dim for successfully constructing such a space. In turn, this will make a case for the claim that we cannot use the standard possible worlds framework to model what is epistemically possible for ordinary agents. (shrink)

In a possible world framework, an agent can be said to know a proposition just in case the proposition is true at all worlds that are epistemically possible for the agent. Roughly, a world is epistemically possible for an agent just in case the world is not ruled out by anything the agent knows. If a proposition is true at some epistemically possible world for an agent, the proposition is epistemically possible for the agent. If a proposition is true at (...) all epistemically possible worlds for an agent, the proposition is epistemically necessary for the agent, and as such, the agent knows the proposition. -/- This framework presupposes an underlying space of worlds that we can call epistemic space. Traditionally, worlds in epistemic space are identified with possible worlds, where possible worlds are the kinds of entities that at least verify all logical truths. If so, given that epistemic space consists solely of possible worlds, it follows that any world that may remain epistemically possible for an agent verifies all logical truths. As a result, all logical truths are epistemically necessary for any agent, and the corresponding framework only allows us to model logically omniscient agents. This is a well-known consequence of the standard possible world framework, and it is generally taken to imply that the framework cannot be used to model non-ideal agents that fall short of logical omniscience. -/- A familiar attempt to model non-ideal agents within a broadly world involving framework centers around the use of impossible worlds where the truths of logic can be false. As we shall see, if we admit impossible worlds where “anything goes” in epistemic space, it is easy to avoid logical omniscience. If any logical falsehood is true at some impossible world, then any logical falsehood may remain epistemically possible for some agent. As a result, we can use an impossible world involving framework to model extremely non-ideal agents that do not know any logical truths. -/- A much harder, and considerably less investigated challenge is to ensure that the resulting epistemic space can also be used to model moderately ideal agents that are not logically omniscient but nevertheless logically competent. Intuitively, while such agents may fail to rule out impossible worlds that verify complex logical falsehoods, they are nevertheless able to rule out impossible worlds that verify obvious logical falsehoods. To model such agents, we need a construction of a non-trivial epistemic space that partly consists of impossible worlds where not "anything goes". This involves imposing substantive constraints on impossible worlds to eliminate from epistemic space, say, trivially impossible worlds that verify obvious logical falsehoods. -/- The central aim of this dissertation is to investigate the nature of such non-trivially impossible worlds and the corresponding epistemic spaces. To flag my conclusions, I argue that successful constructions of epistemic spaces that can safely navigate between the Charybdis of logical omniscience and the Scylla of of “anything goes” are hard, if not impossible to find. (shrink)

_the a priori role_ (for word T). For instance, perhaps anyone who understands the word _water_ is able to know, without appeal to any further a posteriori information, that _water_ refers to the clear, drinkable natural kind whose instances are predominant in our oceans and lakes (if _water_ refers at all.

There are many ways the world might be, for all I know. For all I know, it might be that there is life on Jupiter, and it might be that there is not. It might be that Australia will win the next Ashes series, and it might be that they will not. It might be that my great-grandfather was my great-grandmother's second cousin, and it might be that he was not. It might be that copper is a compound, and it (...) might be that it is not. (shrink)

There is a long tradition in philosophy of using a priori methods to draw conclusions about what is possible and what is necessary, and often in turn to draw conclusions about matters of substantive metaphysics. Arguments like this typically have three steps: first an epistemic claim (about what can be known or conceived), from there to a modal claim (about what is possible or necessary), and from there to a metaphysical claim (about the nature of things in the world).

As tends to be the way with philosophical positions, there are at least as many two-dimensionalisms as there are two-dimensionalists. But painting with a broad brush, there are core epistemological and metaphysical commitments which underlie the two-dimensionalist project, commitments for which I have no sympathies. A sketch of three signi?cant points of disagreement.

A basic intuition about epistemic possibility is the following: It might be that p iff it is open whether p. The standard way of cashing out this intuition is: It might be that p iff it is reconcilable with one’s informational state that p. However, there are certain examples which point to a lacuna in this conception. They indicate that epistemic possibility is restricted to what one can conceive as an alternative, what one can have a cognitive attitude to.

Seth Yalcin has pointed out some puzzling facts about the behaviour of epistemic modals in certain embedded contexts. For example, conditionals that begin ‘If it is raining and it might not be raining, …’ sound unacceptable, unlike conditionals that begin ‘If it is raining and I don’t know it, …’. These facts pose a prima facie problem for an orthodox treatment of epistemic modals, according to which they express propositions about the knowledge of some contextually specified individual or group. This (...) paper develops an explanation of the puzzling facts about embedding within an orthodox framework, using broadly Gricean resources. (shrink)

If knowing requires believing on the basis of evidence that entails what’s believed, we have hardly any knowledge at all. Hence the near-universal acceptance of fallibilism in epistemology: if it's true that "we are all fallibilists now" (Siegel 1997: 164), that's because denying that one can know on the basis of non-entailing evidence1is, it seems, not an option if we're to preserve the very strong appearance that we do know many things (Cohen 1988: 91). Hence the significance of concessive knowledge (...) attributions (CKAs) (Rysiew 2001)—i.e., sentences of the form 'S knows that p, but it's possible that q' (where q entails not-p). To many, utterances of such sentences sound very odd indeed. According to David Lewis (1996: 550), however, such sentences are merely "overt, explicit" statements of fallibilism; if so, their seeming incoherence suggests that, contrary to our everyday epistemic pretensions, "knowledge must be by definition infallible" after all (ibid.: 549). -/- Recently Jason Stanley (2005) has defended fallibilism against the Lewisian worry that overtly fallibilistic speech is incoherent. According yo Stanley, CKAs are not just odd-sounding: in most cases, they are simply false. But this doesn't impugn fallibilism. Insofar as the odd-sounding utterances Lewis cites state the fallibilist idea, the latter portion thereof ('S cannot eliminate a certain possibility in which not-p', e.g.) expresses the idea that the subject's evidence doesn't entail what's (allegedly) known (hence, the negation of any contrary propositions). According to Stanley, however, this is not the best reading of the possibility clauses CKAs contain. On the correct account of the latter, while the sentences Lewis cites are almost always self-contradictory, they don't capture the fallibilist idea after all. Here, we argue that the sentences in question do express precisely the fallibilist idea, but argue that Lewis has nonetheless failed to raise a problem for the latter. In addition, we respond to worries that the resulting view of the semantics of epistemic possibility statements has certain unacceptable consequences. (shrink)

I defend a version of Kripke's claim that the metaphysically necessary and the knowable a priori are independent. On my version, there are two independent families of modal notions, metaphysical and epistemic, neither stronger than the other. Metaphysical possibility is constrained by the laws of nature. Logical validity, I suggest, is best understood in terms of epistemic necessity.

I think that there are good reasons to adopt a relativist semantics for epistemic modal claims such as ``the treasure might be under the palm tree'', according to which such utterances determine a truth value relative to something finer-grained than just a world (or a <world, time> pair). Anyone who is inclined to relativise truth to more than just worlds and times faces a problem about assertion. It's easy to be puzzled about just what purpose would be served by assertions (...) of this kind, and how to understand what we'd be up to in our use of sentences like ``the treasure might be under the palm tree'', if they have such peculiar truth conditions. After providing a very quick argument to motivate a relativist view of epistemic modals, I bring out and attempt to resolve this problem in making sense of the role of assertions with relativist truth conditions. Solving this problem should be helpful in two ways: first, it eliminates an apparently forceful objection to relativism, and second, spelling out the relativist account of assertion and communication will help to make clear just what the relativist position is, exactly, and why it's interesting. (shrink)

The ten new essays in this volume explore various answers to these questions, including those offered by contextualism, relativism, and expressivism.

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 (and the very term ‘epistemic possibility’) should be eschewed in the context of modal epistemology. (shrink)

The philosophy of modality investigates necessity and possibility, and related notions--are they objective features of mind-independent reality? If so, are they irreducible, or can modal facts be explained in other terms? This volume presents new work on modality by established leaders in the field and by up-and-coming philosophers. Between them, the papers address fundamental questions concerning realism and anti-realism about modality, the nature and basis of facts about what is possible and what is necessary, the nature of modal knowledge, modal (...) logic and its relations to necessary existence and to counterfactual reasoning. The general introduction locates the individual contributions in the wider context of the contemporary discussion of the metaphysics and epistemology of modality. (shrink)

We think we have lots of substantial knowledge about the future. But contemporary wisdom has it that indeterminism prevails in such a way that just about any proposition about the future has a non-zero objective chance of being false.2, 3 What should one do about this? One, pessimistic, reaction is scepticism about knowledge of the future. We think this should be something of a last resort, especially since this scepticism is likely to infect alleged knowledge of the present and past. (...) One anti-sceptical strategy is to pin our hopes on determinism, conceding that knowledge of the future is unavailable in an indeterministic world. This is not satisfying either: we would rather not be hostage to empirical fortune in the way that this strategy recommends. A final strategy, one that we shall explore in this paper, is one of reconciliation: knowledge of a proposition is compatible with a subject’s belief having a non-zero objective chance of error.4 Following Williamson, we are interested in tying knowledge to the presence or absence of error in close cases, and so we shall explore the connections between knowledge and objective chance within such a framework. We don’t want to get tangled up here in complications involved in attempting to formulate a necessary and sufficient condition for knowledge in terms of safety. Instead, we will assume the following rough and ready necessary condition: a subject knows P only if she could not easily have falsely believed P.5 Assuming that easiness is to be spelt.. (shrink)

Seven proposed accounts of epistemic possibility are criticized, and a new account is proposed, making use of the notion of having justification for dismissing a proposition. The new account explains intuitions about otherwise puzzling cases, upholds plausible general principles about epistemic possibility, and explains the practical import of epistemic modality judgements. It is suggested that judgements about epistemic possibility function to assess which propositions are worthy of further inquiry.

Real-world agents do not know all consequences of what they know. But we are reluctant to say that a rational agent can fail to know some trivial consequence of what she knows. Since every consequence of what she knows can be reached via chains of trivial consequences of what she knows, we have a paradox. I argue that the problem cannot be dismissed easily, as some have attempted to do. Rather, a solution must give adequate weight to the normative requirements (...) on rational agents’ epistemic states, without treating those agents as mathematically ideal reasoners. I’ll argue that agents can fail to know trivial consequences of what they know, but never determinately. Such cases are epistemic oversights on behalf of the agent in question, and the facts about epistemic oversights are always indeterminate facts. As a result, we are never in a position to assert that such-and-such constitutes an epistemic oversight for agent i (for we may rationally assert only determinate truths). I then develop formal epistemic models according to which epistemic accessibility relations are vague. Given these models, we can show that epistemic oversights always concern indeterminate cases of knowledge. (shrink)

Gaining information can be modelled as a narrowing of epistemic space . Intuitively, becoming informed that such-and-such is the case rules out certain scenarios or would-be possibilities. Chalmers’s account of epistemic space treats it as a space of a priori possibility and so has trouble in dealing with the information which we intuitively feel can be gained from logical inference. I propose a more inclusive notion of epistemic space, based on Priest’s notion of open worlds yet which contains only those (...) epistemic scenarios which are not obviously impossible. Whether something is obvious is not always a determinate matter and so the resulting picture is of an epistemic space with fuzzy boundaries. (shrink)

I discuss three ways of responding to the logical omniscience problems faced by traditional ‘possible worlds’ epistemic logics. Two of these responses were put forward by Hintikka and the third by Cresswell; all three have been influential in the literature on epistemic logic. I show that both of Hintikka's responses fail and present some problems for Cresswell’s. Although Cresswell's approach can be amended to avoid certain unpalatable consequences, the resulting formal framework collapses to a sentential model of knowledge, which defenders (...) of the ‘possible worlds’ approach are frequently critical of. (shrink)

Information is often modelled as a set of relevant possibilities, treated as logically possible worlds. However, this has the unintuitive consequence that the logical consequences of an agent's information cannot be informative for that agent. There are many scenarios in which such consequences are clearly informative for the agent in question. Attempts to weaken the logic underlying each possible world are misguided. Instead, I provide a genuinely psychological notion of epistemic possibility and show how it can be captured in a (...) formal model, which I call a fan. I then show how to use fans to build formal models of being informed, as well as knowledge, belief and information update. (shrink)

Robert Stalnaker is an actualist who holds that merely possible worlds are uninstantiated properties that might have been instantiated. Stalnaker also holds that there are no metaphysically impossible worlds: uninstantiated properties that couldn't have been instantiated. These views motivate Stalnaker's "two dimensional" account of the necessary a posteriori on which there is no single proposition that is both necessary and a posteriori. For a (metaphysically) necessary proposition is true in all (metaphysically) possible worlds. If there were necessary a posteriori propositions, (...) that would mean that there were propositions true in all possible worlds but which could only be known to be true by acquiring empirical evidence. Consider such a purported proposition P. The role of empirical evidence for establishing P's truth would have to be to rule out worlds in which P is false. If there were no such worlds to be ruled out, we would not require evidence for P. But by hypothesis, P is necessary and so true in all metaphysically possible worlds. And on Stalnaker's view, the metaphysically possible worlds are all the worlds there are. So there can be no proposition that is true in all possible worlds, but that we require evidence to know. In this way, the motivation for Stalnaker's two dimensional account of the necessary a posteriori rests on his denying that there are metaphysically impossible Worlds. I argue that given his view of what possible worlds are, Stalnaker has no principled reason for denying that there are metaphysically impossible worlds. If I am right, this undercuts Stalnaker's motivation for his two dimensional account of the necessary a posteriori. (shrink)

Although epistemic possibility figures in several debates, those debates have had relatively little contact with one another. G. E. Moore focused squarely upon analyzing epistemic uses of the phrase, ‘It’s possible that p’, and in doing so he made two fundamental assumptions. First, he assumed that epistemic possibility statements always express the epistemic position of a community, as opposed to that of an individual speaker. Second, he assumed that all epistemic uses of ‘It’s possible that p’ are analyzable in terms (...) of knowledge, not belief. A number of later theorists, including Keith DeRose, provide alternative accounts of epistemic possibility, while retaining Moore’s two assumptions. Neither assumption has been explicitly challenged, but Jaakko Hintikka’s analysis provides a basis for doing so. Drawing upon Hintikka’s analysis, I argue that some epistemic possibility statements express only the speaker’s individual epistemic state, and that contra DeRose, they are not degenerate community statements but a class in their own right. I further argue that some linguistic contexts are belief- rather than knowledge-based, and in such contexts, what is possible for a speaker depends not upon what she knows, but upon what she believes. (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..

By “epistemic modals,” I mean epistemic uses of modal words: adverbs like “necessarily,” “possibly,” and “probably,” adjectives like “necessary,” “possible,” and “probable,” and auxiliaries like “might,” “may,” “must,” and “could.” It is hard to say exactly what makes a word modal, or what makes a use of a modal epistemic, without begging the questions that will be our concern below, but some examples should get the idea across. If I say “Goldbach’s conjecture might be true, and it might be false,” (...) I am not endorsing the Cartesian view that God could have made the truths of arithmetic come out differently. I make the claim not because I believe in the metaphysical contingency of mathematics, but because I know that Goldbach’s conjecture has not yet been proved or refuted. Similarly, if I say “Joe can’t be running,” I am not saying that Joe’s constitution prohibits him from running, or that Joe is essentially a non-runner, or that Joe isn’t allowed to run. My basis for making the claim may be nothing more than that I see Joe’s running shoes hanging on a hook. (shrink)

A strong impossibility is a situation that is epistemically, but not metaphysically, possible. Opponents of strong impossibilities (including Chalmers, Jackson and Stalnaker) have argued that we have “overwhelming reason” to reject and “very little” or “no reason” to think that such impossibilities exist. This partial draft argues that there are strong impossibilities and (very briefly) discusses the manner in which the existence of strong impossibilities is related to some much-discussed arguments in the philosophy of conscious experience. (The full version of (...) the paper will ultimately include a reply to the most significant argument against strong impossibilities, and a (slightly) more involved discussion of the relevance of all of this to issues in the philosophy of conscious experience.). (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.

David’s epistemic understanding of two-dimensional semantics has these two features. First, although he considers at least two construals of epistemically possible worlds, on one of them they are centered metaphysically possible worlds. Second, David intends epistemic two-dimensional semantics to yield a theory of propositional-attitude content, as well as having application to the semantics of natural language expressions. These two features come together in David’s “The Components of Content,” where he deploys the apparatus of epistemic two-dimensional semantics to provide an account (...) of propositional-attitude content, and where, for reasons of simplicity and familiarity, epistemically possible worlds are taken to be centered metaphysically possible worlds. My talk is about this account of content. (shrink)

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

A problem inherited from Kripke is the reconciliation of commitments to various necessities with conflicting intuitions of contingency, intuitions that things "might have turned out otherwise." Kripke's reconciliation strategy is to say that while it is necessary that X is Y, and so impossible for X not to be Y, it is nevertheless epistemically possible for X not to be Y. But what are nonactual epistemic possibilities? Several answers are considered and it is concluded that scenarios adduced to explain away (...) the target intuitions are either themselves impossible, or not fully coherent, or not epistemic in the relevant sense. (shrink)

A problem inherited from Kripke is the reconciliation of commitments to various necessities with conflicting intuitions of contingency, intuitions that things "might have turned out otherwise." Kripke's reconciliation strategy is to say that while it is necessary that X is Y, and so impossible for X not to be Y, it is nevertheless epistemically possible for X not to be Y. But what are nonactual epistemic possibilities? Several answers are considered and it is concluded that scenarios adduced to explain away (...) the target intuitions are either themselves impossible, or not fully coherent, or not epistemic in the relevant sense. (shrink)

Saul Kripke’s discussion of the necessary aposteriori in Naming and Necessity and “Identity and Necessity” -- in which he lays the foundation for distinguishing epistemic from metaphysical possibility, and explaining the relationship between the two – is, in my opinion, one of the outstanding achievements of twentieth century philosophy.1 My aim in this essay is to extract the enduring lessons of his discussion, and disentangle them from certain difficulties which, alas, can also be found there. I will argue that there (...) are, in fact, two Kripkean routes to the necessary aposteriori – one correct and philosophically far-reaching, the other incorrect and philosophically misleading. (shrink)

In ‘Epistemic Modals’ (2007), Seth Yalcin proposes Stalnaker-style semantics for epistemic possibility. He is inspired by John MacFarlane’s ingenious defence of relativism, in which claims of epistemic possibility are made rigidly from the perspective of the assessor’s actual stock of information (rather than from the speaker’s knowledge base or that of his audience or community). The innovations of MacFarlane and Yalcin independently reinforce the modal collapse espoused by Jaakko Hintikka in his 1962 epistemic logic (which relied on the implausible KK (...) principle and heavy idealizations). I respond to this new challenge with fresh objections to the underlying S4 equivalence: p p . I also propose counter-analyses of the intriguing data which Yalcin cites in support of his new semantics. A key collateral motivation for this defence of irredundant iterations is to ward off a threat to higher order vagueness. (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.

: Evidence claims depend on fallible assumptions. Three strategies for making true evidence claims in spite of this fallibility are strengthening the support for those assumptions, weakening conclusions, and using multiple independent tests to produce robust evidence. Reliability itself, understood in frequentist terms, does not explain the usefulness of all three strategies; robustness, in particular, sometimes functions in a way that is not well-characterized in terms of reliability. I argue that, in addition to reliability, the security of evidence claims is (...) of epistemic value, where an evidence claim is secure relative to an epistemic situation if it remains true in all scenarios that are epistemically possible relative to that epistemic situation. (shrink)

We often decide whether a state of affairs is possible (impossible) by trying to mentally depict a scenario (using words, images, etc.) where the state in question obtains (or fails to obtain). These mental acts (broadly thought of as 'conceiving') seem to provide us with an epistemic route to the space of possibilities. The problem this raises is whether conceivability judgments provide justification-conferring grounds for the ensuing possibility-claims (call this the 'conceivability thesis'). Although the question has a long history, contemporary (...) interest in it was, to a large extent, prompted by Kripke's utilization of modal intuitions in the course of propounding certain influential theses in the philosophy of language and mind. The interest has been given a further boost by the recent two-dimensional approach to the Kripkean framework. In this paper, I begin by providing a detailed examination of a most recent attempt (due to Chalmers) to defend the thesis and argue that it is unsuccessful. This is followed by presenting my own gloss on Kripke's explanation of the illusions of contingency and I close by raising a general problem intended to undermine the prospects for a successful defense of the thesis. (shrink)

Expressions of epistemic modality mark the possibility/necessity of the prejacent proposition relative to some body of evidence/knowledge.

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)

What I am calling New Age Relativism is usually proposed as a thesis about the truth-conditions of utterances, where an utterance is an actual historic voicing or inscription of a sentence of a certain type. Roughly, it is the view that, for certain discourses, whether an utterance is true depends not just on the context of its making—when, where, to whom, by whom, in what language, and so on—and the “circumstances of evaluation”—the state of the world in relevant respects—but also (...) on an additional parameter: a context of assessment. Vary the latter and the truth-value of the utterance can vary, even though the context of its making and the associated state of the world remain fixed. (shrink)

Epistemic modal operators give rise to something very like, but also very unlike, Moore's paradox. I set out the puzzling phenomena, explain why a standard relational semantics for these operators cannot handle them, and recommend an alternative semantics. A pragmatics appropriate to the semantics is developed and interactions between the semantics, the pragmatics, and the definition of consequence are investigated. The semantics is then extended to probability operators. Some problems and prospects for probabilistic representations of content and context are explored.