This is a major work in moral philosophy, the long-awaited follow-up to Parfit's 1984 classic Reasons and Persons, a landmark of twentieth-century philosophy. Parfit now presents a powerful new treatment of reasons and a critical examination of the most prominent systematic moral theories, leading to his own ground-breaking conclusion.

In Being Rational and Being Right, Juan Comesaña argues for a cluster of theses related to the rationality of action and belief. His starting point is that rational action requires rational belief but tolerates false belief. From there, Comesaña provides a novel account of empirical evidence according to which said evidence consists of the content of undefeated experiences. This view, which Comesaña calls "Experientialism," differs from the two main views of empirical evidence on offer nowadays: Factualism, according to which our (...) evidence is what we know, and Psychologism, according to which our experiences themselves are evidence. He reasons that Experientialism fares better than these rival views in explaining different features of rational belief and action. Comesaña embeds this discussion in a Bayesian framework, and discusses in addition the problem of normative requirements, the easy knowledge problem, and how Experientialism compares to Evidentialism, Reliabilism, and Comesaña's own (now superseded) Evidentialist Reliabilism. (shrink)

The aim of this paper is to sketch a theory of justified belief. What I have in mind is an explanatory theory, one that explains in a general way why certain beliefs are counted as justified and others as unjustified. Unlike some traditional approaches, I do not try to prescribe standards for justification that differ from, or improve upon, our ordinary standards. I merely try to explicate the ordinary standards, which are, I believe, quite different from those of many classical, (...) e. g., ‘Cartesian’, accounts. (shrink)

The typical epistemology course begins with a discussion of the distinction between justification and knowledge and ends without any discussion of the distinction between justification and excuse. This is unfortunate. If we had a better understanding of the justification-excuse distinction, we would have a better understanding of the intuitions that shape the internalism-externalism debate. My aims in this paper are these. First, I will explain how the kinds of excuses that should interest epistemologists exculpate. Second, I will explain why the (...) intuitions that underwrite the new evil demon argument don't provide support for the internalist claim that justification is just in the head. The positive response that Cohen's example elicits is an indication that the subject should be excused if she violates an epistemic norm, not an indication that no norm has been violated. For just about any conceivable norm we can think of we can imagine situations in which someone violates that norm because they're moved by evidence that misleadingly suggests that they'd conform to it. When that happens, we'll respond positively in just the way we do when we consider Cohen's deceived subjects. When that happens, we cannot say that the subjects' responses were justified because we've stipulated that the subjects' responses contravene the relevant norms. Regardless of whether you think of norms along internalist or externalist lines, you should see that the intuitions that underwrite the new evil demon objection tell us nothing at all about whether a subject conforms to a norm. They tell us nothing about justification. (shrink)

This is the classic work upon which modern-day game theory is based. What began as a modest proposal that a mathematician and an economist write a short paper together blossomed, when Princeton University Press published Theory of Games and Economic Behavior. In it, John von Neumann and Oskar Morgenstern conceived a groundbreaking mathematical theory of economic and social organization, based on a theory of games of strategy. Not only would this revolutionize economics, but the entirely new field of scientific inquiry (...) it yielded--game theory--has since been widely used to analyze a host of real-world phenomena from arms races to optimal policy choices of presidential candidates, from vaccination policy to major league baseball salary negotiations. And it is today established throughout both the social sciences and a wide range of other sciences. (shrink)

The five commentators on my paper ‘Gettier Cases in Epistemic Logic’ (GCEL) demonstrate how fruitful the topic can be. Especially in Brian Weatherson's contribution, and to some extent in those of Jennifer Nagel and Jeremy Goodman, much of the material constitutes valuable development and refinement of ideas in GCEL, rather than criticism. In response, I draw some threads together, and answer objections, mainly those in the papers by Stewart Cohen and Juan Comesaña and by Goodman.

The possibility of justified true belief without knowledge is normally motivated by informally classified examples. This paper shows that it can also be motivated more formally, by a natural class of epistemic models in which both knowledge and justified belief are represented. The models involve a distinction between appearance and reality. Gettier cases arise because the agent's ignorance increases as the gap between appearance and reality widens. The models also exhibit an epistemic asymmetry between good and bad cases that sceptics (...) seem to ignore or deny. (shrink)

The possibility of justified true belief without knowledge is normally motivated by informally classified examples. This paper shows that it can also be motivated more formally, by a natural class of epistemic models in which both knowledge and justified belief (in the relevant sense) are represented. The models involve a distinction between appearance and reality. Gettier cases arise because the agent's ignorance increases as the gap between appearance and reality widens. The models also exhibit an epistemic asymmetry between good and (...) bad cases that sceptics seem to ignore or deny. (shrink)

§I schematises the evidence for an understanding of ‘know’ and other terms of epistemic appraisal that embodies contextualism or subject-sensitive invariantism, and distinguishes between those two approaches. §II argues that although the cases for contextualism and sensitive invariantism rely on a principle of charity in the interpretation of epistemic claims, neither approach satisfies charity fully, since both attribute metalinguistic errors to speakers. §III provides an equally charitable anti-sceptical insensitive invariantist explanation of much of the same evidence as the result of (...) psychological bias caused by salience effects. §IV suggests that the explanation appears to have implausible consequences about practical reasoning, but also that applications of contextualism or sensitive invariantism to the problem of scepticism have such consequences. §V argues that the inevitable difference between appropriateness and knowledge of appropriateness in practical reasoning, closely related to the difference between knowledge and knowledge of knowledge, explains the apparent implausibility. (shrink)

The literature of economic theory, like that of philosophy, abounds in prefaces and prolegomena. Methodology and analysis of concepts take an important place in a science which has not found the sure path of development. But there is no sure path for methodology either. The selfconscious methodology of social science has been largely a borrowing from that of physical science, where procedures have developed to a stage of considerable maturity. But the analogy falls down where guidance is most needed, at (...) the points where social science is most likely to develop new concepts and new types of structure. Philosophers have not been lacking, indeed, to belittle the entire enterprise, and to deny the possibility of anything that could strictly be called social science. (shrink)

I will be arguing that a subject’s belief that p is justified if and only if he knows that p: justification is knowledge. I will start by describing two broad classes of allegedly justified beliefs that do not constitute knowledge and which, hence, cannot be what they are often taken to be if my view is correct. It is far from clear what my view is until I say a lot more about the relevant concept or concepts of justification that (...) concern me. The following section describes several concepts of justification that epistemologists have employed, and, in particular, identifies the two concepts of justification that I claim are coextensive with the concept of knowledge. One of those is the deontological conception of justification: I will be arguing that one ought not believe that p unless one knows that p. I imagine that the major opposition to my view will be that it is simply obvious that there are justified false beliefs, a feeling that I try to dispel in the lengthy section on concepts of justification before I finally get around to giving the main arguments in favor of my view. A view as unorthodox as mine demands more than a single argument: I offer four in the third section. Everyone allows that many people have many unjustified beliefs, and everyone has some unjustified beliefs, but such beliefs appear to be far more prevalent on my view than on more orthodox views. In the last section, I argue that unjustified beliefs, although widespread, are not quite as common as they might appear to be on my view. (shrink)

I argue that perceptual experience provides us with both phenomenal and factive evidence. To a first approximation, we can understand phenomenal evidence as determined by how our environment sensorily seems to us when we are experiencing. To a first approximation, we can understand factive evidence as necessarily determined by the environment to which we are perceptually related such that the evidence is guaranteed to be an accurate guide to the environment. I argue that the rational source of both phenomenal and (...) factive evidence lies in employing perceptual capacities that we have in virtue of being perceivers. In showing that both kinds of evidence have the same rational source, I provide a unified account of perceptual evidence and its rational source in perceptual experience. (shrink)

We argue, contrary to epistemological orthodoxy, that knowledge is not purely epistemic—that knowledge is not simply a matter of truth‐related factors (evidence, reliability, etc.). We do this by arguing for a pragmatic condition on knowledge, KA: if a subject knows that p, then she is rational to act as if p. KA, together with fallibilism, entails that knowledge is not purely epistemic. We support KA by appealing to the role of knowledge‐citations in defending and criticizing actions, and by giving a (...) principled argument for KA, based on the inference rule KB: if a subject knows that A is the best thing she can do, she is rational to do A. In the second half of the paper, we consider and reject the two most promising objections to our case for KA, one based on the Gricean notion of conversational implicature and the other based on a contextualist maneuver. (shrink)

According to Williamson, your evidence consists of all and only what you know (E = K). According to his critics, it doesn’t. While E = K calls for revision, the revisions it calls for are minor. E = K gets this much right. Only true propositions can constitute evidence and anything you know non-inferentially is part of your evidence. In this paper, I defend these two theses about evidence and its possession from Williamson’s critics who think we should break more (...) radically from E = K. (shrink)

We argue, contrary to epistemological orthodoxy, that knowledge is not purely epistemic—that knowledge is not simply a matter of truth‐related factors (evidence, reliability, etc.). We do this by arguing for a pragmatic condition on knowledge, KA: if a subject knows that p, then she is rational to act as if p. KA, together with fallibilism, entails that knowledge is not purely epistemic. We support KA by appealing to the role of knowledge‐citations in defending and criticizing actions, and by giving a (...) principled argument for KA, based on the inference rule KB: if a subject knows that A is the best thing she can do, she is rational to do A. In the second half of the paper, we consider and reject the two most promising objections to our case for KA, one based on the Gricean notion of conversational implicature and the other based on a contextualist maneuver. (shrink)

"[This book] proposes new foundations for the Bayesian principle of rational action, and goes on to develop a new logic of desirability and probabtility."—Frederic Schick, _Journal of Philosophy_.

An infuential twenty-first century philosophical project posits a central role for knowledge: knowledge is more fundamental than epistemic states like belief and justification. So-called “knowledge first” theorists find support for this thought in identifying central theoretical roles for knowledge. I argue that a similar methodology supports a privileged role for more specific category of basic knowledge. Some of the roles that knowledge first theorists have posited for knowledge generally are better suited for basic knowledge.

Believing rationally is epistemically valuable, or so we tend to think. It’s something we strive for in our own beliefs, and we criticize others for falling short of it. We theorize about rationality, in part, because we want to be rational. But why? I argue that how we answer this question depends on how permissive our theory of rationality is. Impermissive and extremely permissive views can give good answers; moderately permissive views cannot.

Judging by our folk appraisals, then, knowledge and action are intimately related. The theories of rational action with which we are familiar leave this unexplained. Moreover, discussions of knowledge are frequently silent about this connection. This is a shame, since if there is such a connection it would seem to constitute one of the most fundamental roles for knowledge. Our purpose in this paper is to rectify this lacuna, by exploring ways in which knowing something is related to rationally acting (...) upon it, defending one particular proposal against anticipated objections. (shrink)

Introduction -- Fallibilism -- Contextualism -- Knowledge and reasons -- Justification -- Belief -- The value and importance of knowledge -- Infallibilism or pragmatic encroachment? -- Appendix I: Conflicts with bayesian decision theory? -- Appendix II: Does KJ entail infallibilism?

Evidentialism is the thesis that epistemic justification for belief supervenes on evidential support. However, we claim there are cases in which, even though two subjects have the same evidential support for a proposition, only one of them is justified. What make the difference are pragmatic factors, factors having to do with our cares and concerns. Our argument against evidentialism is not based on intuitions about particular cases. Rather, we aim to provide a theoretical basis for rejecting evidentialism by defending a (...) “pragmatic” necessary condition on epistemic justification. We argue for the following necessary condition for justification: S is justified in believing that p only if S is rational to prefer (and, hence, act) as if p. In light of this necessary condition, the price of evidentialism is skepticism, or something close to it. (shrink)

I argue that normative requirements should be interpreted as the conditional obligations of dyadic deontic logic. Semantically, normative requirements are conditionals understood as restrictors, the prevailing view of conditionals in linguistics. This means that Modus Ponens is invalid, even when the premises are known.

In this paper I argue that McDowell's brand of disjunctivism about perceptual knowledge is ill‐motivated. First, I present a reconstruction of one main motivation for disjunctivism, in the form of an argument that theories that posit a “highest common factor” between veridical and non‐veridical experiences must be wrong. Then I show that the argument owes its plausibility to a failure to distinguish between justification and warrant (where “warrant” is understood as whatever has to be added to true belief to yield (...) knowledge). (shrink)

In this paper I argue that McDowell's brand of disjunctivism about perceptual knowledge is ill‐motivated. First, I present a reconstruction of one main motivation for disjunctivism, in the form of an argument that theories that posit a “highest common factor” between veridical and non‐veridical experiences must be wrong. Then I show that the argument owes its plausibility to a failure to distinguish between justification and warrant (where “warrant” is understood as whatever has to be added to true belief to yield (...) knowledge). (shrink)

Timothy Williamson has fruitfully exploited formal resources to shed considerable light on the nature of knowledge. In the paper under examination, Williamson turns his attention to Gettier cases, showing how they can be motivated formally. At the same time, he disparages the kind of justification he thinks gives rise to these cases. He favors instead his own notion of justification for which Gettier cases cannot arise. We take issue both with his disparagement of the kind of justification that figures in (...) Gettier cases and the specifics of the formal motivation. (shrink)

I argue that epistemologists’ use of the term ‘epistemic’ has led to serious confusion in the discussion of epistemological issues. The source of the problem is that ‘epistemic’ functions largely as an undefined technical term. I show how this confusion has infected discussions of the nature of epistemic justification, epistemic norms for evidence gathering, and knowledge norms for assertion and belief.

What role, if any, does formal logic play in characterizing epistemically rational belief? Traditionally, belief is seen in a binary way - either one believes a proposition, or one doesn't. Given this picture, it is attractive to impose certain deductive constraints on rational belief: that one's beliefs be logically consistent, and that one believe the logical consequences of one's beliefs. A less popular picture sees belief as a graded phenomenon.

To 'consequentialise' is to take a putatively non-consequentialist moral theory and show that it is actually just another form of consequentialism. Some have speculated that every moral theory can be consequentialised. If this were so, then consequentialism would be empty; it would have no substantive content. As I argue here, however, this is not so. Beginning with the core consequentialist commitment to 'maximising the good', I formulate a precise definition of consequentialism and demonstrate that, given this definition, several sorts of (...) moral theory resist consequentialisation. My strategy is to decompose consequentialism into three conditions, which I call 'agent neutrality', 'no moral dilemmas', and 'dominance', and then to exhibit some moral theories which violate each of these. (shrink)

An argument that takes issue with the contemporary epistemological consensus that justification is distinct from knowledge, proposing instead that justified belief simply is knowledge, and arguing in detail that a belief is justified when ...