Epistemic closure has been a central issue in epistemology over the last forty years. According to versions of the relevant alternatives and subjunctivist theories of knowledge, epistemic closure can fail: an agent who knows some propositions can fail to know a logical consequence of those propositions, even if the agent explicitly believes the consequence (having “competently deduced” it from the known propositions). In this sense, the claim that epistemic closure can fail must be distinguished from the fact that (...) agents do not always believe, let alone know, the consequences of what they know—a fact that raises the “problem of logical omniscience” that has been central in epistemic logic. This paper, part I of II, is a study of epistemic closure from the perspective of epistemic logic. First, I introduce models for epistemic logic, based on Lewis’s models for counterfactuals, that correspond closely to the pictures of the relevant alternatives and subjunctivist theories of knowledge in epistemology. Second, I give an exact characterization of the closure properties of knowledge according to these theories, as formalized. Finally, I consider the relation between closure and higher-order knowledge. The philosophical repercussions of these results and results from part II, which prompt a reassessment of the issue of closure in epistemology, are discussed further in companion papers. As a contribution to modal logic, this paper demonstrates an alternative approach to proving modal completeness theorems, without the standard canonical model construction. By “modal decomposition” I obtain completeness and other results for two non-normal modal logics with respect to new semantics. One of these logics, dubbed the logic of ranked relevant alternatives, appears not to have been previously identified in the modal logic literature. More broadly, the paper presents epistemology as a rich area for logical study. (shrink)

A very natural view about perceptual knowledge is articulated, one on which perceptual knowledge is closely related to perceptual discrimination, and which fits well with a relevant alternatives account of knowledge. It is shown that this kind of proposal faces a problem, and various options for resolving this difficulty are explored. In light of this discussion, a two-tiered relevant alternatives account of perceptual knowledge is offered which avoids the closure problem. It is further shown how this (...) proposal can: accommodate our intuitions about perceptual knowledge and perceptual discrimination in terms of the notion of primary relevance, give an account of how alternatives can be rationally excluded without appeal to perceptual discrimination in terms of the notion of secondary relevance, and deal with the problem posed by inverted Gettier cases, and hence explain what it means to rationally exclude alternatives which are of secondary relevance. (shrink)

According to the Relevant Alternatives (RA) Theory of knowledge, knowing that something is the case involves ruling out (only) the relevant alternatives. The conception of knowledge in epistemic logic also involves the elimination of possibilities, but without an explicit distinction, among the possibilities consistent with an agent’s information, between those relevant possibilities that an agent must rule out in order to know and those remote, far-fetched or otherwise irrelevant possibilities. In this article, I propose formalizations (...) of two versions of the RA theory. Doing so clarifies a famous debate in epistemology, pitting Fred Dretske against David Lewis, about whether the RA theorist should accept the principle that knowledge is closed under known implication, familiar as the K axiom in epistemic logic. Dretske’s case against closure under known implication leads to a study of other closure principles, while Lewis’s defense of closure by appeal to the claimed context sensitivity of knowledge attributions leads to a study of the dynamics of context. Having followed the first lead at length in other work, here I focus more on the second, especially on logical issues associated with developing a dynamic epistemic logic of context change over models for the RA theory. (shrink)

The classic version of the relevant alternatives theory (RAT) identifies knowledge with the elimination of relevant alternatives (Dretske 1981, Stine 1976, Lewis 1996, inter alia). I argue that the RAT is trapped by the problem of the missed clue, in which the subject sees but does not appreciate decisive information.

This paper examines the relationship between perceptual knowledge and discrimination in the light of the so-called ‘relevant alternatives’ intuition. It begins by outlining an intuitive relevant alternatives account of perceptual knowledge which incorporates the insight that there is a close connection between perceptual knowledge and the possession of relevant discriminatory abilities. It is argued, however, that in order to resolve certain problems that face this view, it is essential to recognise an important distinction between favouring (...) and discriminating epistemic support that is often overlooked in the literature. This distinction complicates the story regarding how an alternative becomes relevant, and in doing so weakens the connection between perceptual knowledge and discrimination. The theory that results, however—what I term a ‘two-tiered’ relevant alternatives theory of perceptual knowledge—accommodates many of our intuitions about perceptual knowledge and so avoids the revisionism of some recent proposals in the epistemological literature. (shrink)

Since this paper is for a conference on “Contextualism in Epistemology and Beyond,” I have opted to sketch a retrospective of contextualism in epistemology, including highlights of the “relevant alternatives” approach, given how relevantism and contextualism have developed in tandem. We focus on externalist forms of contextualism, bypassing internalist forms such as Cohen 1988 and Lewis 1996, but much of our discussion will be applicable to contextualism generally. Internalist contextualism is helpfully discussed in papers by Stewart Cohen, Richard (...) Feldman, and Jonathan Vogel, in Tomberlin 1999. (shrink)

Traditionally, skeptics as well as their opponents have agreed that in order to know that p one must be able, by some preferred means, to rule out all the alternatives to p. Recently, however, some philosophers have attempted to avert skepticism not (merely) by weakening the preferred means but rather by articulating a subset of the alternatives to p — the so-called relevant alternatives — and insisting that knowledge that p requires only that we be able (...) (by the preferred means) to rule out members of the set. In this paper I argue that a precise formulation of this new approach reveals it inadequate as a solution to skepticism. (shrink)

The main argument given for relevant alternatives theories of knowledge has been that they answer scepticism about the external world. I will argue that relevant alternatives also solve two other problems that have been much discussed in recent years, a) the bootstrapping problem and b) the apparent conflict between semantic externalism and armchair self-knowledge. Furthermore, I will argue that scepticism and Mooreanism can be embedded within the relevant alternatives framework.

This paper analyzes Deborah Mayo's recent criticism of use-novelty requirement. She claims that her severity criterion captures actual scientific practice better than use-novelty, and that use-novelty is not a necessary condition for severity. Even though certain cases in which evidence used for the construction of the hypothesis can test the hypothesis severely, I do not think that her severity criterion fits better with our intuition about good tests than use-novelty. I argue for this by showing a parallelism in terms of (...) severity between the confidence interval case and what she calls 'gellerization'. To account for the difference between these cases, we need to take into account certain additional considerations like a systematic neglect of relevant alternatives. (shrink)

According to the relevant alternatives theory of knowledge (RA), I know that p only if my evidence eliminates all relevant alternatives to p . Jonathan Schaffer has recently argued that David Lewis's version of RA, which is perhaps the most detailed version yet provided, cannot account for our failure to know in cases involving missed clues, that is, cases in which we see but fail to appreciate decisive evidence. I argue, however, that Lewis's version of RA (...) survives exposure to missed clue cases. Moreover, even though Schaffer maintains that Lewis's Rule of Belief provides no protection against missed clue cases, I argue that we should credit the Rule of Belief with ensuring the survival of Lewis's version of RA. (shrink)

Fred Dretske holds that if one knows something, one need not eliminate every alternative to it but only the relevant alternatives. Besides defending this view in "The Pragmatic Dimension of Knowledge" ("Phil. Stud.", 40, 363-378, n 81), he makes some tentative suggestions about determining when an alternative is relevant. I discuss these suggestions and conclude that there are problems yet to be solved. I do not conclude that there are insoluble problems or that Dretske's approach is on (...) the wrong track. It is, I believe, on the right track. (shrink)

In defending his interest-relative account of knowledge in Knowledge and Practical Interests (2005), Jason Stanley relies heavily on intuitions about several bank cases. We experimentally test the empirical claims that Stanley seems to make concerning our common-sense intuitions about these bank cases. Additionally, we test the empirical claims that Jonathan Schaffer seems to make in his critique of Stanley. We argue that our data impugn what both Stanley and Schaffer claim our intuitions about such cases are. To account for these (...) results, one must develop a better conception of the connection between a subject's interests and her body of knowledge than those offered by Stanley and Schaffer. (shrink)

Recently, Walter Sinott-Armstrong and Justin Snedegar have argued for a general contrastivist theory of reasons. According to the contrastivist account of reasons, all reasons claims should be understood as a relation with an additional place for a contrast class. For example, rather than X being a reason for A to P simpliciter, the contrastivist claims that X is a reason for A to P out of {P,Q,R…}. The main goal of this paper is to argue that the contrastivist account of (...) reasons will be ill-fitted for accommodating certain features of moral reasons. In brief, the reason why the contrastivist analysis fails is that it cannot adequately allow for cases of morally correct whole-hearted action—cases where consideration of any alternate course of action would be misguided. But, if all consideration of alternate courses of action is misguided, then it is hard to see how one can set the relevant contrast class that is essential to the contrastivist view—any contrast class will seem out of place. In addition, I address some of the arguments that have been given in favor of the contrastivist account of reasons and argue that there are at least two ways that the non-contrastivist can respond to these arguments. (shrink)

Many paradoxes have been revealed in the theory of democracy over the years. This article points to yet another paradox at the heart of democracy, whether in its aggregative or deliberative form.The paradox is this: If you are dealing with a large and heterogeneous community, in which people's choices are menu-sensitive in diverse ways, and if people's cognitive capacities preclude them from considering all items on a large menu simultaneouslythen individuals’ choices may be unstable and manipulable depending on how choices (...) over cognitively-manageable subsets of the menu are partitioned and sequenced, 1 and the collective choice may be likewise unstable and manipulable in consequence.Aggregative democracy casts this argument in terms of ‘alternatives’ on the menu for choice. Deliberative democracy casts this argument in terms of ‘considerations’. The same formal problem arises in both cases. (shrink)

Contextualists claim two important virtues for their view. First, contextualism is a non-skeptical epistemology, given the plausible idea that not all contexts invoke the high standards for knowledge needed to generate the skeptical conclusion that we know little or nothing. Second, contextualism is able to preserve closure concerning knowledge – the idea that knowledge is extendable on the basis of competent deduction from known premises. As long as one keeps the context fixed, it is plausible to think that some closure (...) principle can be articulated that will survive scrutiny. Opponents of contextualism often try to gain an advantage over it by claiming that their view mimics these virtues of contextualism as well as having other virtues. A recent example of the same is termed ‘contrastivism," as presented by Jonathan Schaffer. I will argue that the representation made is chimerical, that in fact contrastivism has no hope of mirroring these twin virtues of contextualism. (shrink)

According to David Lewis’s contextualist analysis of knowledge, there can be contexts in which a subject counts as knowing a proposition just because every possibility that this proposition might be false is irrelevant in those contexts. In this paper I argue that, in some cases at least, Lewis’ analysis results in granting people non-evidentially based knowledge of ordinary contingent truths which, intuitively, cannot be known but on the basis of appropriate evidence.

There is much I agree with in Sosa’s paper. His discussion of Stine and Peirce is quite useful; so too his discussion of Dretske in Appendix II. A further issue he focuses on concerns how Contextualists are to give full endorsement to the knowledge-claims of ordinary subjects. Just saying, metalinguistically, that.

So, C. I don’t know that T. Premises 1 and 2 are both plausible. However, C seems false—I do seem to know that there is a tree before me. AI presents a puzzle because its two plausible premises yield a conclusion whose negation is plausible. And no matter whether we accept or reject AI, we find that we must give up something plausible—either premise 1, premise 2, or the negation of C. But which of these should we give up? I (...) call this question the skeptical puzzle.1 Recently, Mark Heller2 has argued that we can solve the skeptical puzzle by giving up premise 2. I argue, however, that Heller does not adequately respond to an objection to his proposed solution. I go on to argue that we can solve the skeptical puzzle by giving up premise 1. (shrink)

In this essay, I will examine Broome’s argument in Weighing Goods that aims to show that moderate Humeanism, according to which any coherent sets of preferences should be rationally acceptable, is not a sustainable view of decision theory. I will focus more specifically on the argument Broome uses to support his claim, and show that although it may get some traction, it does not undermine moderate Humeanism as we know it. After reconstructing Broome’s argument, I argue that standard decision theory (...) supposes that the representation of a decision problem fully captures what is relevant to the agent, and therefore has nothing to say about the legitimacy of the representation in question. I argue that although Broome’s criticism does not jeopardize moderate Humeanism, it does pave the way for a new area of research in decision theory. (shrink)

There are a number of relevant alternatives accounts of knowledge in the literature, including those by contextualists (like Lewis and Cohen), and invariantists (like Dretske). Despite widespread discussion of such views, an explication of the notion of relevance is conspicuously absent from the literature. Without a careful explication of that notion, relevant alternatives accounts resist evaluation. This paper attempts to aid in the evaluation of those accounts, by providing an account of relevance. The account rejects two (...) common presuppositions about the notion of relevance. The account holds that worlds, rather than alternatives, are relevant, and that distant worlds can be relevant. Relevant worlds turn out to be those worlds at which an alternative to one’s belief obtains, and is such that one’s epistemic position (with respect to what one believes at the actual world) is worse than it is at the actual world. (shrink)

In this paper I look at Fred Dretske’s account of information and knowledge as developed in Knowledge and The Flow of Information. In particular, I translate Dretske’s probabilistic definition of information to a modal logical framework and subsequently use this to explicate the conception of information and its flow which is central to his account, including the notions of channel conditions and relevant alternatives. Some key products of this task are an analysis of the issue of information closure (...) and an investigation into some of the logical properties of Dretske’s account of information flow. (shrink)

In this note, I respond to comments by Paul Egré and Xu Zhaoqing on my “Epistemic Closure and Epistemic Logic I: Relevant Alternatives and Subjunctivism” (Journal of Philosophical Logic).

There’s something deeply right in the idea that knowledge requires an ability to discriminate truth from falsity. Failing to incorporate some version of the discrimination requirement into one’s epistemology generates cases of putative knowledge that are at best problematic. On the other hand, many theories that include a discrimination requirement thereby appear to entail violations of closure. This prima facie tension is resolved nicely in Jonathan Schaffer’s contrastivism, which I describe herein. The contrastivist take on relevant alternatives is (...) implausible, however, and this then threatens to undermine contrastivism’s anti-skeptical results. (shrink)

P. Kyle Stanford defends the problem of unconceived alternatives, which maintains that scientists are unlikely to conceive of all the scientifically plausible alternatives to the theories they accept. Stanford’s argument has been criticized on the grounds that the failure of individual scientists to conceive of relevant alternatives does not entail the failure of science as a corporate body to do so. I consider two replies to this criticism and find both lacking. In the process, I argue (...) that Stanford does not provide evidence that there are likely scientifically plausible unconceived alternatives to scientific theories accepted now and in the future. (shrink)

Scalar implicatures depend on alternatives in order to avoid the symmetry problem. I argue for a structure-sensitive characterization of these alternatives: the alternatives for a structure are all those structures that are at most as complex as the original one. There have been claims in the literature that complexity is irrelevant for implicatures and that the relevant condition is the semantic notion of monotonicity. I provide new data that pose a challenge to the use of monotonicity (...) and that support the structure-sensitive definition. I show that what appeared to be a problem for the complexity approach is overcome once an appropriate notion of complexity is adopted, and that upon closer inspection, the argument in favor of monotonicity turns out to be an argument against it and in favor of the complexity approach. (shrink)

This article addresses and resolves an epistemological puzzle that has attracted much attention in the recent literature—namely, the puzzle arising from Moorean anti-sceptical reasoning and the phenomenon of transmission failure. The paper argues that an appealing account of Moorean reasoning can be given by distinguishing carefully between two subtly different ways of thinking about justification and evidence. Once the respective distinctions are in place we have a simple and straightforward way to model both the Wrightean position of transmission failure and (...) the Moorean position of dogmatism. The approach developed in this article is, accordingly, ecumenical in that it allows us to embrace two positions that are widely considered to be incompatible. The paper further argues that the Moorean Puzzle can be resolved by noting the relevant distinctions and our insensitivity towards them: once we carefully tease apart the different senses of ‘justified’ and ‘evidence’ involved, the bewilderment caused by Moore’s anti-sceptical strategy subsides. (shrink)

This chapter argues that epistemologists should replace a “standard alternatives” picture of knowledge, assumed by many fallibilist theories of knowledge, with a new “multipath” picture of knowledge. The chapter first identifies a problem for the standard picture: fallibilists working with this picture cannot maintain even the most uncontroversial epistemic closure principles without making extreme assumptions about the ability of humans to know empirical truths without empirical investigation. The chapter then shows how the multipath picture, motivated by independent arguments, saves (...) fallibilism from this problem. The multipath picture is based on taking seriously the idea that there can be multiple paths to knowing some propositions about the world. An overlooked consequence of fallibilism is that these multiple paths to knowledge may involve ruling out different sets of alternatives, which should be represented in a fallibilist picture of knowledge. The chapter concludes by considering inductive knowledge and strong epistemic closure from this multipath perspective. (shrink)

Single-premise epistemic closure is the principle that: if one is in an evidential position to know that P where P entails Q, then one is in an evidential position to know that Q. In this paper, I defend the viability of opposition to closure. A key task for such an opponent is to precisely formulate a restricted closure principle that remains true to the motivations for abandoning unrestricted closure but does not endorse particularly egregious instances of closure violation. I focus (...) on two brands of epistemic theory that naturally incorporate closure restrictions. The first type holds that the truth value of a knowledge ascription is relative to a relevant question. The second holds that the truth value of a knowledge ascription is relative to a relevant topic. For each approach, I offer a formalization of a leading theory from the literature and use this formalization to evaluate the theory’s adequacy in terms of a precise set of desiderata. I conclude that neither theory succeeds in meeting these desiderata, casting doubt on the viability of the underlying approaches. Finally, I offer a novel variant of the topic-sensitive approach that fares better. (shrink)

This essay deals with a selected part of an epistemological controversy provided by Tūsī in response to the skeptical arguments reported by Rāzī that is related to what might be called "intellectual skepticism," or skepticism regarding the judgments of the intellect, particularly in connection with self-evident principles. It will be shown that Rāzī has cited and exposed a position that seems to be no less than a medieval version of empiricism. Tūsī, in contrast, has presented us with a position that (...) rejects such empiricism. The comparative aim of this essay is to draw attention to some similarities as well as some points of divergence between the kind of skeptical debate we are focusing on here, and some relevant epistemological discussions in the later traditions in the West. ". (shrink)

Amartya Sen argues that it is not, after all, irrational to reverse preferences when your choices are amplified by an ‘irrelevant’ alternative. He offers examples such as the agent who always picks the next-to-largest piece of cake. Given a choice between a larger and smaller piece, I will prefer the smaller one. But when a third and largest piece in added to my alternatives, I will now prefer the formerly largest piece over the smallest piece. This violates ‘contraction consistency’: (...) a third alternative should not have made any difference in my preferences regarding the first two. Such examples are shown to rely on descriptions which omit features crucial to choice. These features, and all identifying features relevant to my decision, should be included in the descriptions of the alternatives. An adequate description does not smuggle norms into the overt act of choice, but it does include the non-normative characteristics without which my decision-rules, if any, cannot be applied. When alternatives are adequately described, Sen’s inconsistencies disappear. The result is a clearer and more resillent, but also less aggressive notion of behavioral consistency. (shrink)

One of the central considerations to be taken into account in evaluating the ethics of compensation for donated plasma is respect for donor autonomy. And one of the main arguments against compensated donation systems is that many donors do or would come from circumstances of poverty that restrict their alternatives in a way that compromises those donors’ autonomy. In this paper, I develop and defend a novel version of this “compromised autonomy argument” which improves upon extant versions by employing (...) a more nuanced account of the relationship between alternatives and autonomy. According to the version of that argument I offer, donors lack autonomy with respect to the sale of their plasma if their economic circumstances leave them with no choice but to sell their plasma on the basis of a desire they have had no choice but to hold. After explicating the key terms of this argument, I examine its policy implications. I argue that, given several reasonable empirical assumptions, my argument implies that a majority of individuals whose income falls below a specified threshold would indeed lack autonomy with respect to the sale of their plasma. Most individuals whose income falls above that threshold, on the other hand, would be able to autonomously sell their plasma. I argue that respect for donor autonomy therefore speaks in favor of an income-restricted system of compensated donation which permits collection centers to purchase plasma from those whose income falls above the relevant threshold, but not those below it. (shrink)

Manuscript originally written in 1995. Discusses various attempts to characterize alternatives relevant for deliberation and for the formulation of act-consequentialist accounts of what actions ought to be performed.

Probabilistic theories of “should” and “ought” face a predicament. At first blush, it seems that such theories must provide different lexical entries for the epistemic and the deontic interpretations of these modals. I show that there is a new style of premise semantics that can avoid this consequence in an attractively conservative way.