In these challenging pages, Unger argues for the extreme skeptical view that, not only can nothing ever be known, but no one can ever have any reason at all for anything. A consequence of this is that we cannot ever have any emotions about anything: no one can ever be happy or sad about anything. Finally, in this reduction to absurdity of virtually all our supposed thought, he argues that no one can ever believe, or even say, that anything is (...) the case. (shrink)

Knowledge and its Limits presents a systematic new conception of knowledge as a kind of mental stage sensitive to the knower's environment. It makes a major contribution to the debate between externalist and internalist philosophies of mind, and breaks radically with the epistemological tradition of analyzing knowledge in terms of true belief. The theory casts new light on such philosophical problems as scepticism, evidence, probability and assertion, realism and anti-realism, and the limits of what can be known. The arguments are (...) illustrated by rigorous models based on epistemic logic and probability theory. The result is a new way of doing epistemology and a notable contribution to the philosophy of mind. (shrink)

Scientific reasoning is—and ought to be—conducted in accordance with the axioms of probability. This Bayesian view—so called because of the central role it accords to a theorem first proved by Thomas Bayes in the late eighteenth ...

We consider a paradox involving indicative conditionals (‘ifs’) and deontic modals (‘oughts’). After considering and rejecting several standard options for resolv- ing the paradox—including rejecting various premises, positing an ambiguity or hidden contextual sensitivity, and positing a non-obvious logical form—we offer a semantics for deontic modals and indicative conditionals that resolves the paradox by making modus ponens invalid. We argue that this is a result to be welcomed on independent grounds, and we show that rejecting the general validity of modus (...) ponens is compatible with vindicating most ordinary uses of modus ponens in reasoning. (shrink)

Operational epistemology is, to a first approximation, the attempt to provide cognitive rules such that one is in principle always in a position to know whether one is complying with them. In Knowledge and its Limits, I argue that the only such rules are trivial ones. In this paper, I generalize the argument in several ways to more thoroughly probabilistic settings, in order to show that it does not merely demonstrate some oddity of the folk epistemological conception of knowledge. Some (...) of the generalizations involve a formal semantic framework for treating epistemic probabilities of epistemic probabilities and expectations of expectations. The upshot is that operational epistemology cannot work, and that knowledge-based epistemology has the right characteristics to avoid its problems. (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)

Several philosophers have argued that natural selection will favor reliable belief formation; others have been more skeptical. These traditional approaches to the evolution of rationality have been either too sketchy or else have assumed that phenotypic plasticity can be equated with having a mind. Here I develop a new model to explore the functional utility of belief and desire formation mechanisms, and defend the claim that natural selection favors reliable inference methods in a broad, but not universal, range of circumstances.

This paper argues for externalism about justification on the basis of thought experiments. I present cases in which two individuals are intrinsically and introspectively indistinguishable and in which intuitively, one is justified in believing that p while the other is not. I also examine an argument for internalism based on the ideas that we have privileged access to whether or not our own beliefs are justified and that only internalism is compatible with this privilege. I isolate what I take to (...) be the most plausible form of privileged access to justification and show that it is compatible with externalism. (shrink)

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)

Newcomb's problem and similar cases show the need to incorporate causal distinctions into the theory of rational decision; the usual noncausal decision theory, though simpler, does not always give the right answers. I give my own version of causal decision theory, compare it with versions offered by several other authors, and suggest that the versions have more in common than meets the eye.

Handbook of the History of Logic, vol. 10, eds. Dov Gabbay, Stephan Hartmann, and John Woods, forthcoming.

I shall be mainly concerned with the question ‘What is personal propositional knowledge?’. This question is obviously quite narrowly focused, in three respects. In the first place, there is impersonal as well as personal knowledge. Second, a distinction is often drawn between propositional knowledge and practical knowledge. And third, as well as asking what knowledge is, it is also possible to ask whether and how knowledge of various kinds can be acquired: causal knowledge, a priori knowledge, moral knowledge, and so (...) on. I shall dwell briefly on each of these three points. First, there is the distinction between personal and impersonal knowledge – in other words, between the psychological concept of knowledge and the social one.1 We use the concept of knowledge to describe the cognitive condition of individuals; but we also use it to describe the progress of scientific and historical research. So for example we can speak or enquire about the state of knowledge in a particular field of biology or history. And if we do so, we are evidently not concerned with what anyone in particular knows about, say, the genetics of fruit flies or the career of Charlemagne, but rather with what the scientific or academic community knows. Needless to say, there is a close connection between personal and impersonal knowledge. But ‘It is known that p’ does not simply mean ‘Someone or other. (shrink)

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)

The doyen of living English philosophers, by these reflections, took hold of and changed the outlook of a good many other philosophers, if not quite enough. He did so, essentially, by assuming that talk of freedom and responsibility is talk not of facts or truths, in a certain sense, but of our attitudes. His more explicit concern was to look again at the question of whether determinism and freedom are consistent with one another -- by shifting attention to certain personal (...) rather than moral attitudes, first of all gratitude and resentment. In the end, he arrived at a kind of Compatibilist or, as he says, Optimist conclusion. That is no doubt a recommendation but not the largest recommendation of this splendidly rich piece of philosophy. (shrink)

The author identifies and defines the features of traditional utilitarian theories which account for their appeal, demonstrates that no theory which is exclusively act-oriented can have all the properties that ultilitarians have attempted to build into their theories, and develops a new theory co-operative utilitarianism.

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)

Knowledge-first evidentialism combines the view that it is rational to believe what is supported by one's evidence with the view that one's evidence is what one knows. While there is much to be said for the view, it is widely perceived to fail in the face of cases of reasonable error—particularly extreme ones like new Evil Demon scenarios (Wedgwood, 2002). One reply has been to say that even in such cases what one knows supports the target rational belief (Lord, 201x, (...) this volume). I spell out two versions of the strategy. The direct one uses what one knows as the input to principles of rationality such as conditionalization, dominance avoidance, etc. I argue that it fails in hybrid cases that are Good with respect to one belief and Bad with respect to another. The indirect strategy uses what one knows to determine a body of supported propositions that is in turn the input to principles of rationality. I sketch a simple formal implementation of the indirect strategy and show that it avoids the difficulty. I conclude that the indirect strategy offers the most promising way for knowledge-first evidentialists to deal with the New Evil Demon problem. (shrink)

A recent view in contemporary epistemology holds that practical reasoning is governed by an epistemic norm. Evidence for the existence of this norm is provided by the ways in which we assess our actions and reasoning on the basis of whether certain epistemic conditions are satisfied. Philosophers disagree on what this norm is—whether it is knowledge, justified belief or something else. Nobody however challenges the claim that practical reasoning is governed by such a norm. I argue that assuming the existence (...) of an epistemic norm of practical reasoning is neither the only nor the best way to accommodate the available data. I introduce and defend an alternative account that avoids the assumption. According to this account, the relevant epistemic assessments of action and reasoning are instrumental assessments relative to the regulation conditions of a non-epistemic norm. (shrink)

Every choice we make is set against a background of massive ignorance about our past, our future, our circumstances, and ourselves. Philosophers are divided on the moral significance of such ignorance. Some say that it has a direct impact on how we ought to behave - the question of what our moral obligations are; others deny this, claiming that it only affects how we ought to be judged in light of the behaviour in which we choose to engage - the (...) question of what responsibility we bear for our choices. Michael Zimmerman claims that our ignorance has an important bearing on both questions, and offers an account of moral obligation and moral responsibility that is sharply at odds with the prevailing wisdom. His book will be of interest to a wide range of readers in ethics. (shrink)

In this paper, I develop a theory of how claims about an agent’s normative reasons are sensitive to the epistemic circumstances of this agent, which preserves the plausible ideas that reasons are facts and that reasons can be discovered in deliberation and disclosed in advice. I argue that a plausible theory of this kind must take into account the difference between synchronic and diachronic reasons, i.e. reasons for acting immediately and reasons for acting at some later point in time. I (...) provide a general account of the relation between synchronic and diachronic reasons, demonstrate its implications for the evidence-sensitivity of reasons and finally present and defend an argument for my view. (shrink)

Derek Parfit presents the third volume of On What Matters, his landmark work of moral philosophy. Parfit develops further his influential treatment of reasons, normativity, the meaning of moral discourse, and the status of morality. He engages with his critics, and shows the way to resolution of their differences.

Sometimes our intentions and beliefs exhibit a structure that proves us to be irrational. This dissertation is concerned with the question of whether we ought (or have at least good reason) to avoid such irrationality. The thesis defends the normativity of rationality by presenting a new solution to the problems that arise from the common assumption that we ought to be rational. The argument touches upon many other topics in the theory of normativity, such as the form and the content (...) of rational standards or requirements, the preconditions of criti¬cism, and the function of reasons in deliberation and advice. Over and above an exten¬sive assessment of the problems discussed in the literature, the thesis provides a detailed defence of a reason-response conception of rationality, a novel, evidence-relative account of reasons, and an explanation of structural irrationality in terms of these accounts. (shrink)

John Gibbons presents an original account of epistemic normativity. Belief seems to come with a built-in set of standards or norms. One task is to say where these standards come from. But the more basic task is to say what those standards are. In some sense, beliefs are supposed to be true. Perhaps they’re supposed to constitute knowledge. And in some sense, they really ought to be reasonable. Which, if any of these is the fundamental norm of belief? The book (...) argues against the teleological or instrumentalist conception of rationality that sees being reasonable as a means to our more objective aims, either knowledge or truth. And it tries to explain both the norms of knowledge and of truth in terms of the fundamental norm, the one that tells you to be reasonable. The importance of being reasonable is not explained in terms of what it will get you, or what you think it will get you, or what it would get you if only things were different. The requirement to be reasonable comes from the very idea of what a genuine requirement is. That’s where the built-in standards governing belief come from, and that’s what they are. (shrink)

There is a debate in normative ethics about whether or not our moral obligations depend solely on either our evidence concerning, or our beliefs about, the world. Subjectivists maintain that they do and objectivists maintain that they do not. I shall offer some arguments in support of objectivism and respond to the strongest argument for subjectivism. I shall also briefly consider the significance of my discussion to the debate over whether one’s future voluntary actions are relevant to one’s current moral (...) obligations. (shrink)

A review of Michael Zimmerman's wonderful book, _Living with Uncertainty_. Among other things, I argue that there might be something wrong with combining possibilism and perspectivism.

Many philosophers hold that whether an act is overall morally obligatory is an ‘objective’ matter, many that it is a ‘subjective’ matter, and some that it is both. The idea that it is or can be both may seem to promise a helpful answer to the question ‘What ought I to do when I do not know what I ought to do?’ In this article, three broad views are distinguished regarding what it is that obligation essentially concerns: the maximization of (...) actual value, the maximization of expected value, and the perceived maximization of actual value. The first and third views are rejected; the second view is then refined and defended. The unfortunate upshot is that there may be no very helpful answer to the question just mentioned. As to the question posed in the title of the article, the answer unsurprisingly depends on what ‘objective’ and ‘subjective’ are taken to mean. (Published Online November 24 2006). (shrink)

In this paper, I present and explore some ideas about how factive emotional states and factive perceptual states each relate to knowledge and reasons. This discussion will shed light on the so-called ‘perceptual model’ of the emotions.

This book is about normativity and reasons.

This major work challenges some widely held positions in epistemology - those of Peirce and Popper on the one hand and those of Quine and Kuhn on the other.

Is rationality normative, in the sense that we ought to be rational, in our actions and attitudes? Recently, the claim that rationality is normative has faced several challenges. In this paper, I will take up these challenges, and aim to vindicate the normativity of rationality in the face of them. I will begin, in part 1, by outlining these challenges, and then discussing, and criticizing, some that have been offered to them in the literature. Then, in part 2, I will (...) offer my own, unified response to these challenges. (shrink)

The author identifies and defines the features of traditional utilitarian theories which account for their appeal, demonstrates that no theory which is "exclusively act-oriented" can have all the properties that ultilitarians have attempted to build into their theories, and develops a new theory "co-operative utilitarianism", which is radically different than traditional theories.

Twentieth century philosophers introduced the distinction between “objective rightness” and “subjective rightness” to achieve two primary goals. The first goal is to reduce the paradoxical tension between our judgments of what is best for an agent to do in light of the actual circumstances in which she acts and what is wisest for her to do in light of her mistaken or uncertain beliefs about her circumstances. The second goal is to provide moral guidance to an agent who may be (...) uncertain about the circumstances in which she acts, and hence is unable to use her standard moral principle directly in deciding what to do. This paper distinguishes two important senses of “moral guidance”; proposes criteria of adequacy for accounts of subjective rightness; canvasses existing definitions for “subjective rightness”; finds them all deficient; and proposes a new and more successful account. It argues that each comprehensive moral theory must include multiple principles of subjective rightness to address the epistemic situations of the full range of moral decision-makers, and shows that accounts of subjective rightness formulated in terms of what it would reasonable for the agent to believe cannot provide that guidance. (shrink)

Reconhecido centro de formação profissional em carreiras jurídicas, o IDC oferece Especialização, preparação para Exame de Ordem e Cursos de Extensão em mais de 20 áreas do Direito, aprofundando os conhecimentos de advogados e bacharéis. Possui também graduação em Filosofia, além de promover Cursos Preparatórios para Concursos em diversas áreas, obtendo excelentes resultados de aprovação graças à preocupação constante na qualificação e excelência de seu corpo docente e infra-estrutura.

In his important book Knowledge and Practical Interests, Jason Stanley advances a proposal about knowledge and the semantics of knowledge ascriptions which he calls interest-relative invariantism. A theory of knowledge ascriptions of the form ‘A knows that S’ is invariantist.