Here we challenge the orthodoxy according to which abduction is an a posteriori mode of inference. We start by providing a case study illustrating how abduction can justify a philosophical claim not justifiable by empirical evidence alone. While many grant abduction's epistemic value, nearly all assume that abductive justification is a posteriori, on grounds that our belief in abduction's epistemic value depends on empirical evidence about how the world contingently is. Contra this assumption, we argue, first, that our belief in (...) abduction’s epistemic value is not and could not be justified a posteriori, and second, that attention to the roles experience plays in abductive justification supports taking abduction to be an a priori mode of inference. We close by highlighting how our strategy for establishing the a priority of abduction positively contrasts with strategies in Bonjour (1998), Swinburne (2001), and Peacocke (2004) aiming to establish the a priority of certain ampliative modes of inference or abductive principles. (shrink)

William James famously tells us that there are two main goals for rational believers: believing truth and avoiding error. I argues that epistemic consequentialism—in particular its embodiment in epistemic utility theory—seems to be well positioned to explain how epistemic agents might permissibly weight these goals differently and adopt different credences as a result. After all, practical versions of consequentialism render it permissible for agents with different goals to act differently in the same situation. -/- Nevertheless, I argue that epistemic consequentialism (...) doesn’t allow for this kind of permissivism and goes on to argue that this reveals a deep disanalogy between decision theory and the formally similar epistemic utility theory. This raises the question whether epistemic utility theory is a genuinely consequentialist theory at all. (shrink)

A discussion of L.A. Paul's 'Transformative Experience' from an Author Meets Critics session at the 2015 Pacific APA.

In these comments I briefly discuss three aspects of the empiricist account of the epistemic role of experience that Anil Gupta develops in his Empiricism and Experience. First, I discuss the motivations Gupta offers for the claim that the given in experience should be regarded as reliable. Second, I discuss two different ways of conceiving of the epistemic significance of the phenomenology of experience. And third, I discuss whether Gupta's account is able to deliver the anti-skeptical results he intends it (...) to. I close by suggesting that, once fully fleshed out, Gupta's account is best understood in terms of the fusion of certain core ideas within both the empiricist and the rationalist traditions. (shrink)

Extended Rationality: A Hinge Epistemology provides a novel account of the structure of epistemic justification. Its central claim builds upon Wittgenstein's idea in On Certainty that epistemic justifications hinge on some basic assumptions and that epistemic rationality extends to these very hinges. It exploits these ideas to address major problems in epistemology, such as the nature of perceptual justifications, external world skepticism, epistemic relativism, the epistemic status of basic logical laws, of the Principle of the Uniformity of Nature, of our (...) belief in the existence of the past and of other minds, and the nature of testimonial justification. Along the way, further technical issues, such as the scope of the Principle of Closure of epistemic operators under known entailment, the notion of transmission failure, and the existence of entitlements are addressed in new and illuminating ways. (shrink)

Do the facts of evolution generate an epistemic challenge to moral realism? Some think so, and many “evolutionary debunking arguments” have been discussed in the recent literature. But they are all murky right where it counts most: exactly which epistemic principle is meant to take us from evolutionary considerations to the skeptical conclusion? Here, I will identify several distinct species of evolutionary debunking argument in the literature, each one of which relies on a distinct epistemic principle. Drawing on recent work (...) in epistemology, I will show that most of these initially plausible principles are false, spoiling the arguments that rely on them. And we will see that each argument threatens only one popular view of moral psychology: a “Representationalist” view on which our moral judgments rely crucially on a mental intermediary—e.g. a sentiment, gut reaction, or affect-laden intuition—delivered by our evolved moral faculty. In the end, only one evolutionary debunking argument remains a menace: an “ Argument from Symmetry ” that I will introduce to the literature. But we will see that it should worry only all naturalists, pressuring them into a trilemma: give up moral realism, accept a rationalism that is incongruous with naturalism, or give up naturalism. Non-naturalists are free and clear. (shrink)

Does rationality require logical omniscience? Our best formal theories of rationality imply that it does, but our ordinary evaluations of rationality seem to suggest otherwise. This paper aims to resolve the tension by arguing that our ordinary evaluations of rationality are not only consistent with the thesis that rationality requires logical omniscience, but also provide a compelling rationale for accepting this thesis in the first place. This paper also defends an account of apriori justification for logical beliefs that is designed (...) to explain the rational requirement of logical omniscience. On this account, apriori justification for beliefs about logic has its source in logical facts, rather than psychological facts about experience, reasoning, or understanding. This account has important consequences for the epistemic role of experience in the logical domain. In a slogan, the epistemic role of experience in the apriori domain is not a justifying role, but rather an enabling and disabling role. (shrink)

A lot of good philosophy is done in the armchair, but is nevertheless a posteriori. This paper clarifies and then defends that claim. Among the a posteriori activities done in the armchair are assembling and evaluating commonplaces; formulating theoretical alternatives; and integrating well-known past a posteriori discoveries. The activity that receives the most discussion, however, is the application of theoretical virtues to choose philosophical theories: the paper argues that much of this is properly seen as a posteriori.

How should intellectualists respond to apparent Gettier-style counterexamples? Stanley offers an orthodox response which rejects the claim that the subjects in such scenarios possess knowledge-how. I argue that intellectualists should embrace a revisionary response according to which knowledge-how is a distinctively practical species of knowledge-that that is compatible with Gettier-style luck.

I argue for a theory that combines elements of reliabilism and evidentialism.

I begin by describing the solution to the problem of skepticism propounded by contextualists, which constitutes the background of the rest of the paper. I then address the question of what happens when a skeptic and a non-skeptic are confronted in dialogue to the standards in play for correct knowledge ascription, on the assumption that contextualism about knowledge is right. I argue against Keith DeRose that there are reasons, both intuitive and theoretical, to conclude that the standards will be raised (...) in such a way as to make the skeptic’s denials of knowledge true. Next, I argue, again against DeRose, for the claim that that conclusion has significant theoretical consequences. In particular, I argue that, if the standards do tend to rise, then there is a serious problem for contextualist answers to skepticism. The problem, which is sometimes called the factivity problem, is that the contextualist position is not possible to state properly unless we know in the theoretical context that skeptical hypotheses do not hold. (shrink)

This article investigates the claim that some truths are fundamentally or really true — and that other truths are not. Such a distinction can help us reconcile radically minimal metaphysical views with the verities of common sense. I develop an understanding of the distinction whereby Fundamentality is not itself a metaphysical distinction, but rather a device that must be presupposed to express metaphysical distinctions. Drawing on recent work by Rayo on anti-Quinean theories of ontological commitments, I formulate a rigourous theory (...) of the notion. In the final sections, I show how this package dovetails with ' interpretationist' theories of meaning to give sober content to thought that some things — perhaps sets, or gerrymandered mereological sums — can be 'postulated into existence'. (shrink)

I lay out the framework for my theory of sensory imagination in “Imagining as a guide to possibility.” Sensory imagining involves mental imagery , and crucially, in describing the content of imagining, I distinguish between qualitative content and assigned content. Qualitative content derives from the mental image itself; for visual imaginings, it is what is “pictured.” For example, visually imagine the Philadelphia Eagles defeating the Pittsburgh Steelers to win their first Super Bowl. You picture the greenness of the field and (...) the football’s brown oblong shape. Some of what you imagine isn’t explicitly pictured, however. That it is Sunday, that it is the Super Bowl: these facts are assigned. (shrink)

According to the extended knowledge account of assertion, we should only assert and act on what we know. Call this the ‘Knowledge Norm’. Because moral and prudential rules prohibit morally and prudentially unacceptable actions and assertions, they can, familiarly, override the Knowledge Norm. This, however, raises the question of whether other epistemic norms, too, can override the Knowledge Norm. The present chapter offers an affirmative answer to this question and then argues that the Knowledge Norm is derived from a more (...) fundamental norm that demands that we do not hinder intellectual flourishing. As the fundamental epistemic norm can come into conflict with the Knowledge Norm, it is sometimes permissible to assert and act on what we don’t know. The chapter concludes with a discussion of the consequences of this insight for the extended knowledge account of assertion. (shrink)

Elsewhere, I have challenged virtue epistemology and argued that it doesn’t square with mundane cases of extended cognition. Kelp (forthcoming, this journal) and Greco (forthcoming) have responded to my charges, the former by questioning the force of my argument, the latter by developing a new virtue epistemology. Here I consider both responses. I show first that Kelp mischaracterizes my challenge. Subsequently, I identify two new problems for Greco’s new virtue epistemology.

This paper argues for and explores the implications of the following epistemological principle for knowability a priori (with 'Ka' abbreviating 'it is knowable a priori that'). -/- (AK) For all ϕ, ψ such that ϕ semantically presupposes ψ: if Ka(ϕ), Ka(ψ). -/- Well-known arguments for the contingent a priori and a priori knowledge of logical truth founder when the semantic presuppositions of the putative items of knowledge are made explicit. Likewise, certain kinds of analytic truth turn out to carry semantic (...) presuppositions that make them ineligible as items of a priori knowledge. -/- On a happier note, I argue that (AK) offers an appealing, theory-neutral explanation of the a posteriori character of certain necessary identities, as well as an interesting rationalization for a commonplace linguistic maneuver in philosophical work on the a priori. (shrink)

According to a doctrine that I call “Cartesianism”, knowledge – at least the sort of knowledge that inquirers possess – requires having a reason for belief that is reflectively accessible as such. I show that Cartesianism, in conjunction with some plausible and widely accepted principles, entails the negation of a popular version of Fallibilism. I then defend the resulting Cartesian Infallibilist position against popular objections. My conclusion is that if Cartesianism is true, then Descartes was right about this much: for (...) S to know that p, S must have reasons for believing that p which are such that S can know, by reflection alone, that she has those reasons, and that she could not possibly have those reasons if p is not true. Where Descartes went wrong was in thinking that our ordinary, fallible, non-theologically grounded sources of belief (e.g., perception, memory, testimony), cannot provide us with such reasons. (shrink)

Suppose that knowledge and ignorance are complements in the sense of being mutually exclusive: for person S and fact p, either S knows that p or is ignorant that p. Understood in this way, ignorance amounts to a lack or absence of knowledge: S is ignorant that p if and only if it is not the case that S knows that p. Let us call the thesis that knowledge and ignorance are opposites the “Complement Thesis”. In this article, I discuss (...) its deployment in an ingenious new argument advanced by Alvin Goldman and Erik Olsson (2009) which, if sound, establishes that there is a kind of knowledge that amounts to nothing more than true belief. I rebut their argument and in doing so delineate some important epistemological lessons brought to light by the contrast between ignorance and knowledge. (shrink)

This paper is about three of the most prominent debates in modern epistemology. The conclusion is that three prima facie appealing positions in these debates cannot be held simultaneously. The first debate is scepticism vs anti-scepticism. My conclusions apply to most kinds of debates between sceptics and their opponents, but I will focus on the inductive sceptic, who claims we cannot come to know what will happen in the future by induction. This is a fairly weak kind of scepticism, and (...) I suspect many philosophers who are generally anti-sceptical are attracted by this kind of scepticism. Still, even this kind of scepticism is quite unintuitive. I’m pretty sure I know (1) on the basis of induction. (1) It will snow in Ithaca next winter. Although I am taking a very strong version of anti-scepticism to be intuitively true here, the points I make will generalise to most other versions of scepticism. (Focussing on the inductive sceptic avoids some potential complications that I will note as they arise.) The second debate is a version of rationalism vs empiricism. The kind of rationalist I have in mind accepts that some deeply contingent propositions can be known a priori, and the empiricist I have in mind denies this. Kripke showed that there are contingent propositions that can be known a priori. One example is Water is the watery stuff of our acquaintance. (‘Watery’ is David Chalmers’s nice term for the properties of water by which folk identify it.) All the examples Kripke gave are of propositions that are, to use Gareth Evans’s term, deeply necessary (Evans, 1979). It is a matter of controversy presently just how to analyse Evans’s concepts of deep necessity and contingency, but most of the controversies are over details that are not important right here. I’ll simply adopt Stephen Yablo’s recent suggestion: a proposition is deeply contingent if it could have turned out to be true, and could have turned out to be false (Yablo, 2002)1. Kripke did not provide examples of any deeply contingent propositions knowable a priori, though nothing he showed rules out their existence.. (shrink)

Applying good inductive rules inside the scope of suppositions leads to implausible results. I argue it is a mistake to think that inductive rules of inference behave anything like 'inference rules' in natural deduction systems. And this implies that it isn't always true that good arguments can be run 'off-line' to gain a priori knowledge of conditional conclusions.

I argue that you can have a priori knowledge of propositions that neither are nor appear necessarily true. You can know a priori contingent propositions that you recognize as such. This overturns a standard view in contemporary epistemology and the traditional view of the a priori, which restrict a priori knowledge to necessary truths, or at least to truths that appear necessary.

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

Humeanism is “the thesis that the whole truth about a world like ours supervenes on the spatiotemporal distribution of local qualities.” (Lewis, 1994, 473) Since the whole truth about our world contains truths about causation, causation must be located in the mosaic of local qualities that the Humean says constitute the whole truth about the world. The most natural ways to do this involve causation being in some sense extrinsic. To take the simplest possible Humean analysis, we might say that (...) c causes e iff throughout the mosaic events of the same type as c are usually followed by events of type e. For short, the causal relation is the constant conjunction relation. Whether this obtains is determined by the mosaic, so this is a Humean theory, but it isn’t determined just by c and e themselves, so whether c causes e is extrinsic to the pair. Now this is obviously a bad theory of causation, but the fact that causation is extrinsic is retained even by good Humean theories of causation. John Hawthorne (2004) objects to this feature of Humeanism. I’m going to argue that his arguments don’t work, but first we need to clear up three preliminaries about causation and intrinsicness. (shrink)

(revisions posted 12/5/2006) to appear in Internalism and Externalism in Semantics and Epistemology, ed. by Sanford Goldberg (to be published by Oxford in 2006 or 2007) Michael McKinsey formulated an argument that raises a puzzle about the relation between externalism about content and our introspective awareness of content. The puzzle goes like this: it seems like I can know the contents of my thoughts by introspection alone; but philosophical reflection tells me that the contents of those thoughts are externalist, and (...) so I couldn. (shrink)

The evidential role of experience in justifying beliefs has been at the center of debate in philosophy in recent years. One view is that experience, or seeming, can confer immediate justification on belief in virtue of its representational phenomenology. Call this view “representational dogmatism.” Another view is that experience confers immediate justification on belief in virtue of its relational phenomenology. Call this view “relational dogmatism.” The goal of this paper is to pit these two versions of dogmatism against each other (...) in terms of their ability to account for ampliative, or non-deductive, inferential justification. I will argue that only the representational view can provide a plausible account of this type of justification. (shrink)

We offer a general framework for theorizing about the structure of knowledge and belief in terms of the comparative normality of situations compatible with one’s evidence. The guiding idea is that, if a possibility is sufficiently less normal than one’s actual situation, then one can know that that possibility does not obtain. This explains how people can have inductive knowledge that goes beyond what is strictly entailed by their evidence. We motivate the framework by showing how it illuminates knowledge about (...) the future, knowledge of lawful regularities, knowledge about parameters measured using imperfect instruments, the connection between knowledge, belief, and probability, and the dynamics of knowledge and belief in response to new evidence. (shrink)

According to epistemological disjunctivism (ED), in paradigmatic cases of perceptual knowledge, a subject, S, has perceptual knowledge that p in virtue of being in possession of reasons for her belief that p which are both factive and reflectively accessible to S. It has been argued that ED is better placed than both knowledge internalism and knowledge externalism to undercut underdetermination-based skepticism. I identify several principles that must be true if ED is to be uniquely placed to attain this goal. After (...) that, I use those principles to formulate a diachronic skeptical argument. This argument yields the counterintuitive conclusion that understanding a global skeptical hypothesis is all it takes for a rational subject to lose all her perceptual knowledge of the world. Next, I show that a popular Austinian move must reject one or another of the principles that underlie ED. I close by delineating a novel strategy that can block the diachronic skeptical argument while preserving all the principles. The key idea is that perceptual knowledge is grounded in primitive, perceptual and recognitional abilities. This view sheds new light on some puzzling features of global skepticism that have been noted by Descartes and Hume, among others. (shrink)

The debate between exceptionalists and anti-exceptionalists about logic is often framed as concerning whether the justification of logical theories is a priori or a posteriori (for short: whether logic is a priori or a posteriori). As we substantiate (S1), this framing more deeply encodes the usual anti-exceptionalist thesis that logical theories, like scientific theories, are abductively justified, coupled with the common supposition that abduction is an a posteriori mode of inference, in the sense that the epistemic value of abduction is (...) (and, indeed, must be) a posteriori. In past work, however, we have argued that this common supposition is incorrect: abduction is an a priori mode of inference, in the sense that the epistemic value of abduction is (and indeed, must be) a priori (Biggs and Wilson 2017a, 2017b, 2019). After sketching our two main argumentative strategies for this conclusion (S2), we go on (S3) to consider its import on the proper understanding of anti-exceptionalism about logic. (shrink)

There is an ever-growing literature on what exactly the condition or criterion is that enables some (but not all) debunking arguments to undermine our beliefs. In this paper, I develop a novel schema for debunking argumentation, arguing that debunking arguments generally have a simple and valid form, but that whether or not they are sound depends on the particular aetiological explanation which the debunker provides in order to motivate acceptance of the individual premises. The schema has three unique features: (1) (...) it satisfies important desiderata for what any acceptable account of debunking would have to look like; (2) it is consistent with the inductively supported claim that there is no special debunking principle; and (3) it coheres with the plausible claim that what makes debunking arguments unique is that they rely on so-called genealogies for the justification of their premises. (shrink)

Is the fact that our universe contains fine-tuned life evidence that we live in a multiverse? Ian Hacking and Roger White influentially argue that it is not. We approach this question through a systematic framework for self-locating epistemology. As it turns out, leading approaches to self-locating evidence agree that the fact that our own universe contains fine-tuned life indeed confirms the existence of a multiverse. This convergence is no accident: we present two theorems showing that, in this setting, any updating (...) rule that satisfies a few reasonable conditions will have the same feature. The conclusion that fine-tuned life provides evidence for a multiverse is hard to escape. (shrink)

How is moral knowledge possible? This paper defends the anti-Humean thesis that we can acquire moral knowledge by deduction from wholly non-moral premises. According to Hume’s Law, as it has become known, we cannot deduce an ‘ought’ from an ‘is’, since it is “altogether inconceivable how this new relation can be a deduction from others, which are entirely different from it” (Hume, 1739, 3.1.1). This paper explores the prospects for a deductive theory of moral knowledge that rejects Hume’s Law.

The principle of epistemic closure is the claim that what is known to follow from knowledge is known to be true. This intuitively plausible idea is endorsed by a vast majority of knowledge theorists. There are significant problems, however, that have to be addressed if epistemic closure – closed knowledge – is endorsed. The present essay locates the problem for closed knowledge in the separation it imposes between knowledge and evidence. Although it might appear that all that stands between knowing (...) the truth of the premises of a valid inference and knowledge of its conclusion is inferring it from the premises, the evidence for each of the premises may jointly count against the conclusion. The intuitive view regarding inferred knowledge says one thing, the evidence says another. One epistemological framework that seems to have the resources to resolve this tension endorses the view that knowledge always requires conclusive evidence. A second framework resolves the tension by limiting the scope of the closure principle. Only inferences drawn directly from propositions contained in the scope of a single knowledge operator are considered closed. The aim of the present essay is to revive the unpopular third option, the idea that knowledge is open. The essay proceeds by arguing that in different ways the two former frameworks only succeed in relocating the problem, not in resolving it. The first framework, the infallibilist view, relocates the problem to a sharp separation between knowledge of the occurrences of events from knowledge of their chance of occurring, a separation leading to several significant additional problems. The fallibilist view, the second framework, in endorsing closure neglects to take into full account the ways in which evidence fails to be transitive. For instance, evidence can count in favor of a conjunction while counting against each of its conjuncts. This fact, which is argued for in the essay on probabilistic as well as non-probabilistic grounds, is used as the foundation of an argument against closed knowledge that can be used as a way to understand several of the most fundamental challenges of epistemology. Not only can an open knowledge view that is based on open evidence resolve all these problems in a simple and natural way, it can also respond to formidable challenges that significantly hinder other open knowledge views. There are good reasons, then, to view both knowledge and evidence as open. (shrink)

Introduction to Philosophy: Epistemology engages first-time philosophy readers on a guided tour through the core concepts, questions, methods, arguments, and theories of epistemology—the branch of philosophy devoted to the study of knowledge. After a brief overview of the field, the book progresses systematically while placing central ideas and thinkers in historical and contemporary context. The chapters cover the analysis of knowledge, the nature of epistemic justification, rationalism vs. empiricism, skepticism, the value of knowledge, the ethics of belief, Bayesian epistemology, social (...) epistemology, and feminist epistemologies. Along the way, instructors and students will encounter a wealth of additional resources and tools: chapter learning outcomes, key terms, images of philosophers and related art, useful diagrams and tables, boxes containing excerpts and other supplementary material, questions for reflection, suggestions for further reading, and a glossary. For an undergraduate survey epistemology course, Introduction to Philosophy: Epistemology is ideal when used as a main text paired with primary sources and scholarly articles. For an introductory philosophy course, select book chapters are best used in combination with chapters from other books in the Introduction to Philosophy open textbook series (edited by Christina Hendricks). (shrink)

According to the traditional analysis of propositional knowledge (which derives from Plato's account in the Meno and Theaetetus), knowledge is justified true belief. This chapter develops the traditional analysis, introduces the famous Gettier and lottery problems, and provides an overview of prospective solutions. In closing, I briefly comment on the value of conceptual analysis, note how it has shaped the field, and assess the state of post-Gettier epistemology.

This paper endeavors to establish foundations for the interaction between hyperintensional semantics and two-dimensional indexing. I examine the significance of the semantics, by developing three, novel interpretations of the framework. The first interpretation provides a characterization of the distinction between fundamental and derivative truths. The second interpretation demonstrates how the elements of decision theory are definable within the semantics, and provides a novel account of the interaction between probability measures and hyperintensional grounds. The third interpretation concerns the contents of the (...) types of intentional action, and the semantics is shown to resolve a puzzle concerning the role of intention in action. Topic-sensitive two-dimensional truthmaker semantics can be interpreted epistemically and metasemantically. (shrink)

In this paper I will draw attention to an important route to external world skepticism, which I will call confidence skepticism. I will argue that we can defang confidence skepticism (though not a meeker ‘argument from might’ which has got some attention in the 20th century literature on external world skepticism) by adopting a partially psychologistic answer to the problem of priors. And I will argue that certain recent work in the epistemology of mathematics and logic provides independent support for (...) such psychologism. (shrink)

Williamson and others have recently argued against the significance of the a priori/a posteriori distinction. My aim in this paper is to explain, defend, and expand upon one of these arguments. In the first section, I develop in some detail a line of argument sketched in Williamson. In the second section, I consider two replies to Williamson and show that they miss the structure of the challenge, as I understand it. The problem for defenders of the distinction is to find (...) a way to draw it without leaving out some paradigmatic a priori knowledge or including some paradigmatic a posteriori knowledge. Interestingly, the two replies fail in opposite directions. I then consider the view that, in cases of a priori knowledge, one needs only understanding and some reasoning to gain justified belief. Such reasoning, I argue, should itself not be dependent on experience. Next, I consider, and reject, the attempt to spell out independence of experience for reasoning based on a link between the modal and epistemic status of the proposition involved. Finally, I provide some general grounds to think that the role of experience in forming a reasoning competence, while not evidential, is not devoid of normative value. The main reason is that the normative status of intellectual competences depends on the experiences that constitute their acquisition and development. (shrink)

A good surgeon knows how to perform a surgery; a good architect knows how to design a house. We value their know-how. We ordinarily look for it. What makes it so valuable? A natural response is that know-how is valuable because it explains success. A surgeon’s know-how explains their success at performing a surgery. And an architect’s know-how explains their success at designing houses that stand up. We value know-how because of its special explanatory link to success. But in virtue (...) of what is know-how explanatorily linked to success? This essay provides a novel argument for the thesis that know-how’s special link to success is to be explained at least in part in terms of its being, or involving, a doxastic attitude that is epistemically alike propositional knowledge. It is argued that the role played by know-how in explaining intentional success shows that the epistemic differences between know-how and knowledge, if any, are less than usually thought; and that "revisionary intellectualism", the view that know-how is true belief that might well fall short of knowledge, is not really a stable position. If its explanatory link to success is what makes know-how valuable, an upshot of my argument is that the value of know-how is due, to a considerable extent, to its being, or involving, a kind of propositional knowledge. (shrink)

Timothy Williamson (1992, 224–5) and Ernest Sosa (1996) have ar- gued that knowledge requires one to be safe from error. Something is said to be safe from happening iff it does not happen at “close” worlds. I expand here on a puzzle noted by John Hawthorne (2004, 56n) that suggests the need for two notions of closeness. Counterfac- tual closeness is a matter of what could in fact have happened, given the specific circumstances at hand. The notion is involved in (...) the semantics for counterfactuals and is the one epistemologists have typically assumed. Normalized closeness is rather a matter of what could typically have happened, that is, what would go on in a class of normal alternatives to actuality, irrespectively of whether or not they could have happened in the circumstances at hand. (shrink)

It has been argued recently that dogmatism in epistemology is incompatible with Bayesianism. That is, it has been argued that dogmatism cannot be modelled using traditional techniques for Bayesian modelling. I argue that our response to this should not be to throw out dogmatism, but to develop better modelling techniques. I sketch a model for formal learning in which an agent can discover a posteriori fundamental epistemic connections. In this model, there is no formal objection to dogmatism.

Modal knowledge accounts like sensitivity or safety face a problem when it comes to knowing propositions that are necessarily true because the modal condition is always fulfilled no matter how random the belief forming method is. Pritchard models the anti-luck condition for knowledge in terms of the modal principle safety. Thus, his anti-luck epistemology faces the same problem when it comes to logical necessities. Any belief in a proposition that is necessarily true fulfills the anti-luck condition and, therefore, qualifies as (...) knowledge. Miščević shares Pritchard’s take on epistemic luck and acknowledges the resulting problem. In his intriguing article “Armchair Luck: Apriority, Intellection and Epistemic Luck” Miščević suggests solving the problem by supplementing safety with a virtue theoretic condition-“agent stability”-which he also spells out in modal terms. I will argue that Miščević is on the right track when he suggests adding a virtue-theoretic component to the safety condition. However, it should not be specified modally but rather in terms of performances that manifest competences. (shrink)

This book concerns the foundations of epistemic modality and hyperintensionality and their applications to the philosophy of mathematics. I examine the nature of epistemic modality, when the modal operator is interpreted as concerning both apriority and conceivability, as well as states of knowledge and belief. The book demonstrates how epistemic modality and hyperintensionality relate to the computational theory of mind; metaphysical modality and hyperintensionality; the types of mathematical modality and hyperintensionality; to the epistemic status of large cardinal axioms, undecidable propositions, (...) and abstraction principles in the philosophy of mathematics; to the modal and hyperintensional profiles of the logic of rational intuition; and to the types of intention, when the latter is interpreted as a hyperintensional mental state. Chapter 2 argues for a novel type of expressivism based on the duality between the categories of coalgebras and algebras, and argues that the duality permits of the reconciliation between modal and hyperintensional cognitivism and modal and hyperintensional expressivism. I also develop a novel, topic-sensitive truthmaker semantics for dynamic epistemic logic, and develop a novel, dynamic two-dimensional semantics grounded in two-dimensional hyperintensional Turing machines. Chapter 3 provides an abstraction principle for epistemic (hyper-)intensions. Chapter 4 advances a topic-sensitive two-dimensional truthmaker semantics, and provides three novel interpretations of the framework along with the epistemic and metasemantic. Chapter 5 applies the fixed points of the modal μ-calculus in order to account for the iteration of epistemic states in a single agent, by contrast to availing of modal axiom 4 (i.e. the KK principle). The fixed point operators in the modal μ-calculus are rendered hyperintensional, which yields the first hyperintensional construal of the modal μ-calculus in the literature and the first application of the calculus to the iteration of epistemic states in a single agent instead of the common knowledge of a group of agents. Chapter 6 advances a solution to the Julius Caesar problem based on Fine's `criterial' identity conditions which incorporate conditions on essentiality and grounding. Chapter 7 provides a ground-theoretic regimentation of the proposals in the metaphysics of consciousness and examines its bearing on the two-dimensional conceivability argument against physicalism. The topic-sensitive epistemic two-dimensional truthmaker semantics developed in chapters 2 and 4 are availed of in order for epistemic states to be a guide to metaphysical states in the hyperintensional setting. -/- Chapters 8-12 provide cases demonstrating how the two-dimensional hyperintensions of hyperintensional, i.e. topic-sensitive epistemic two-dimensional truthmaker, semantics, solve the access problem in the epistemology of mathematics. Chapter 8 examines the interaction between my hyperintensional semantics and the axioms of epistemic set theory, large cardinal axioms, the Epistemic Church-Turing Thesis, the modal axioms governing the modal profile of Ω-logic, Orey sentences such as the Generalized Continuum Hypothesis, and absolute decidability. These results yield inter alia the first hyperintensional Epistemic Church-Turing Thesis and hyperintensional epistemic set theories in the literature. Chapter 9 examines the modal and hyperintensional commitments of abstractionism, in particular necessitism, and epistemic hyperintensionality, epistemic utility theory, and the epistemology of abstraction. I countenance a hyperintensional semantics for novel epistemic abstractionist modalities. I suggest, too, that higher observational type theory can be applied to first-order abstraction principles in order to make first-order abstraction principles recursively enumerable, i.e. Turing machine computable, and that the truth of the first-order abstraction principle for hyperintensions is grounded in its being possibly recursively enumerable and the machine being physically implementable. Chapter 10 examines the philosophical significance of hyperintensional Ω-logic in set theory and discusses the hyperintensionality of metamathematics. Chapter 11 provides a modal logic for rational intuition and provides a hyperintensional semantics. Chapter 12 avails of modal coalgebras to interpret the defining properties of indefinite extensibility, and avails of hyperintensional epistemic two-dimensional semantics in order to account for the interaction between interpretational and objective modalities and the truthmakers thereof. This yields the first hyperintensional category theory in the literature. I invent a new mathematical trick in which first-order structures are treated as categories, and Vopenka's principle can be satisfied because of the elementary embeddings between the categories and generate Vopenka cardinals in the category of Set in category theory. Chapter 13 examines modal responses to the alethic paradoxes. Chapter 14 examines, finally, the modal and hyperintensional semantics for the different types of intention and the relation of the latter to evidential decision theory. (shrink)

This book concerns the foundations of epistemic modality and hyperintensionality and their applications to the philosophy of mathematics. I examine the nature of epistemic modality, when the modal operator is interpreted as concerning both apriority and conceivability, as well as states of knowledge and belief. The book demonstrates how epistemic modality and hyperintensionality relate to the computational theory of mind; metaphysical modality and hyperintensionality; the types of mathematical modality and hyperintensionality; to the epistemic status of large cardinal axioms, undecidable propositions, (...) and abstraction principles in the philosophy of mathematics; to the modal and hyperintensional profiles of the logic of rational intuition; and to the types of intention, when the latter is interpreted as a hyperintensional mental state. Chapter 2 argues for a novel type of expressivism based on the duality between the categories of coalgebras and algebras, and argues that the duality permits of the reconciliation between modal and hyperintensional cognitivism and modal and hyperintensional expressivism. I also develop a novel, topic-sensitive truthmaker semantics for dynamic epistemic logic, and develop a novel, dynamic two-dimensional semantics grounded in two-dimensional hyperintensional Turing machines. Chapter 3 provides an abstraction principle for epistemic (hyper-)intensions. Chapter 4 advances a topic-sensitive two-dimensional truthmaker semantics, and provides three novel interpretations of the framework along with the epistemic and metasemantic. Chapter 5 applies the fixed points of the modal μ-calculus in order to account for the iteration of epistemic states in a single agent, by contrast to availing of modal axiom 4 (i.e. the KK principle). The fixed point operators in the modal μ-calculus are rendered hyperintensional, which yields the first hyperintensional construal of the modal μ-calculus in the literature and the first application of the calculus to the iteration of epistemic states in a single agent instead of the common knowledge of a group of agents. Chapter 6 advances a solution to the Julius Caesar problem based on Fine's `criterial' identity conditions which incorporate conditions on essentiality and grounding. Chapter 7 provides a ground-theoretic regimentation of the proposals in the metaphysics of consciousness and examines its bearing on the two-dimensional conceivability argument against physicalism. The topic-sensitive epistemic two-dimensional truthmaker semantics developed in chapters 2 and 4 are availed of in order for epistemic states to be a guide to metaphysical states in the hyperintensional setting. -/- Chapters 8-12 provide cases demonstrating how the two-dimensional hyperintensions of hyperintensional, i.e. topic-sensitive epistemic two-dimensional truthmaker, semantics, solve the access problem in the epistemology of mathematics. Chapter 8 examines the interaction between my hyperintensional semantics and the axioms of epistemic set theory, large cardinal axioms, the Epistemic Church-Turing Thesis, the modal axioms governing the modal profile of Ω-logic, Orey sentences such as the Generalized Continuum Hypothesis, and absolute decidability. These results yield inter alia the first hyperintensional Epistemic Church-Turing Thesis and hyperintensional epistemic set theories in the literature. Chapter 9 examines the modal and hyperintensional commitments of abstractionism, in particular necessitism, and epistemic hyperintensionality, epistemic utility theory, and the epistemology of abstraction. I countenance a hyperintensional semantics for novel epistemic abstractionist modalities. I suggest, too, that higher observational type theory can be applied to first-order abstraction principles in order to make first-order abstraction principles recursively enumerable, i.e. Turing machine computable, and that the truth of the first-order abstraction principle for hyperintensions is grounded in its being possibly recursively enumerable and the machine being physically implementable. Chapter 10 examines the philosophical significance of hyperintensional Ω-logic in set theory and discusses the hyperintensionality of metamathematics. Chapter 11 provides a modal logic for rational intuition and provides a hyperintensional semantics. Chapter 12 avails of modal coalgebras to interpret the defining properties of indefinite extensibility, and avails of hyperintensional epistemic two-dimensional semantics in order to account for the interaction between interpretational and objective modalities and the truthmakers thereof. This yields the first hyperintensional category theory in the literature. I invent a new mathematical trick in which first-order structures are treated as categories, and Vopenka's principle can be satisfied because of the elementary embeddings between the categories and generate Vopenka cardinals in the category of Set in category theory. Chapter 13 examines modal responses to the alethic paradoxes. Chapter 14 examines, finally, the modal and hyperintensional semantics for the different types of intention and the relation of the latter to evidential decision theory. (shrink)

Experimental restrictionists have challenged philosophers’ reliance on intuitions about thought experiment cases based on experimental findings. According to the expertise defense, only the intuitions of philosophical experts count—yet the bulk of experimental philosophy consists in studies with lay people. In this paper, we argue that direct strategies for assessing the expertise defense are preferable to indirect strategies. A direct argument in support of the expertise defense would have to show: first, that there is a significant difference between expert and lay (...) intuitions; second, that expert intuitions are superior to lay intuitions; and third, that expert intuitions accord with the relevant philosophical consensus. At present, there is only little experimental evidence that bears on these issues. To advance the debate, we conducted two new experiments on intuitions about knowledge with experts and lay people. Our results suggest that the intuitions of epistemological experts are superior in some respects, but they also pose an unexpected challenge to the expertise defense. Most strikingly, we found that even epistemological experts tend to ascribe knowledge in fake-barn-style cases. This suggests that philosophy, as a discipline, might fail to adequately map the intuitions of its expert practitioners onto a disciplinary consensus. (shrink)