Nozick analyzes fundamental issues, such as the identity of the self, knowledge and skepticism, free will, the foundations of ethics, and the meaning of life.

This book presents an attempt to develop a theory of knowledge and a philosophy of mind using ideas derived from the mathematical theory of communication developed by Claude Shannon. Information is seen as an objective commodity defined by the dependency relations between distinct events. Knowledge is then analyzed as information caused belief. Perception is the delivery of information in analog form for conceptual utilization by cognitive mechanisms. The final chapters attempt to develop a theory of meaning by viewing meaning as (...) a certain kind of information-carrying role. (shrink)

1 Knowledge and Justification This book is an investigation of one central problem which arises in the attempt to give a philosophical account of empirical ...

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)

This book offers a philosophy for error-prone humans trying to understand messy systems in the real world.

In this book and in its sequels, Warrant and Proper Function and Warranted Christian Belief, I examine the nature of epistemic warrant, that quantity, enough of which distinguishes knowledge from mere true belief. Contemporary epistemologists seldom focus attention on the nature of warrant; and when they do, they display deplorable diversity: some claim that what turns true belief into knowledge is a matter of epistemic dutifulness, others that it goes by coherence, and still others that it is conferred by reliability. (...) I shall argue that none of these claims is correct, and (in Warrant and Proper Function) suggest a more satisfactory alternative. In the present book, I survey current contributions to the discussion of warrant and neighboring issues. I begin with internalism, looking first at the carefully crafted foundationalist internalism of Roderick Chisholm (Chs. 2 and 3). To better understand Chisholm and other internalists, however, I first make a preliminary excursus (Ch 1) into the classical internalism of Descartes, Locke, and others. After Chisholmian internalism, I turn to coherentism, which for classificatory purposes I take as a form of internalism. In the next three chapters, I consider coherentism taken generally (Ch. 4), the specific version of coherentism developed by Laurence BonJour (Ch. 5), and contemporary Bayesian versions of coherentism (Chs. 6 and 7). Next (Ch. 8), there is the more attenuated internalism of John Pollock, which I see as a transition from internalism to externalism. Finally, I examine the reliabilist and externalist views of William Alston, Fred Dretske, and Alvin Goldman (Ch. 9), and close with a preview of Warrant and Proper Function (Ch. 10). (shrink)

Consider the skeptic about the external world. Let’s straightaway concede to such a skeptic that perception gives us no conclusive or certain knowledge about our surroundings. Our perceptual justification for beliefs about our surroundings is always defeasible—there are always possible improvements in our epistemic state which would no longer support those beliefs. Let’s also concede to the skeptic that it’s metaphysically possible for us to have all the experiences we’re now having while all those experiences are false. Some philosophers dispute (...) this, but I do not. The skeptic I want to consider goes beyond these familiar points to the much more radical conclusion that our perceptual experiences can’t give us any knowledge or even justification for believing that our surroundings are one way rather than another. (shrink)

In this book, Ernest Sosa explains the nature of knowledge through an approach originated by him years ago, known as virtue epistemology. Here he provides the first comprehensive account of his views on epistemic normativity as a form of performance normativity on two levels. On a first level is found the normativity of the apt performance, whose success manifests the performer's competence. On a higher level is found the normativity of the meta-apt performance, which manifests not necessarily first-order skill or (...) competence but rather the reflective good judgment required for proper risk assessment. Sosa develops this bi-level account in multiple ways, by applying it to issues much disputed in recent epistemology: epistemic agency, how knowledge is normatively related to action, the knowledge norm of assertion, and the Meno problem as to how knowledge exceeds merely true belief. A full chapter is devoted to how experience should be understood if it is to figure in the epistemic competence that must be manifest in the truth of any belief apt enough to constitute knowledge. Another takes up the epistemology of testimony from the performance-theoretic perspective. Two other chapters are dedicated to comparisons with ostensibly rival views, such as classical internalist foundationalism, a knowledge-first view, and attributor contextualism. The book concludes with a defense of the epistemic circularity inherent in meta-aptness and thereby in the full aptness of knowing full well. (shrink)

A wide-ranging study of the central concepts in epistemology - belief, truth and knowledge. Professor Armstrong offers a dispositional account of general beliefs and of knowledge of general propositions. Belief about particular matters of fact are described as structures in the mind of the believer which represent or 'map' reality, while general beliefs are dispositions to extend the 'map' or introduce casual relations between portions of the map according to general rules. 'Knowledge' denotes the reliability of such beliefs as representations (...) of reality. Within this framework Professor Armstrong offers a distinctive account of many of the main questions in general epistemology - the relations between beliefs and language, the notions of proposition, concept and idea, the analysis of truth, the varieties of knowledge, and the way in which beleifs and knowledge are supported by reasons. The book as a whole if offered as a contribution to a naturalistic account of man. (shrink)

... and Normative Epistemology The Distinction Between Metaepistemology and Normative Epistemology Although this terminology is relatively new, ...

In this impressive second edition of Theory of Knowledge, Keith Lehrer introduces students to the major traditional and contemporary accounts of knowing. Beginning with the traditional definition of knowledge as justified true belief, Lehrer explores the truth, belief, and justification conditions on the way to a thorough examination of foundation theories of knowledge,the work of Platinga, externalism and naturalized epistemologies, internalism and modern coherence theories, contextualism, and recent reliabilist and causal theories. Lehrer gives all views careful examination and concludes that (...) external factors must be matched by appropriate internal factors to yield knowledge. This match of internal and external factors follows from Lehrer’s new coherence theory of undefeated justification. In addition to doing justice to the living epistemological traditions, the text smoothly integrates several new lines that will interest scholars. Also, a feature of special interest is Lehrer’s concept of a justification game.This second edition of Theory of Knowledge is a thoroughly revised and updated version that contains several completely new chapters. Written by a well-known scholar and contributor to modern epistemology, this text is distinguished by clarity of structure, accessible writing, and an elegant mix of traditional material, contemporary ideas, and well-motivated innovation. (shrink)

One of the many problems that would have t o be solved by a satisfactory theory of empirical knowledge, perhaps the most central is a general structural problem which I shall call the epistemic regress problem: the problem of how to avoid an in- finite and presumably vicious regress of justification in ones account of the justifica- tion of empirical beliefs. Foundationalist theories of empirical knowledge, as we shall see further below, attempt t o avoid the regress by locating a (...) class of empirical beliefs whose justification does not depend on that of other empirical beliefs. Extemalist theories, the topic of the present paper, represent one species of foundationalism. (shrink)

This book offers solutions to two persistent and I believe closely related problems in epistemology. The first problem is that of drawing a principled distinction between perception and inference: what is the difference between seeing that something is the case and merely believing it on the basis of what we do see? The second problem is that of specifying which beliefs are epistemologically basic (i.e., directly, or noninferentially, justified) and which are not. I argue that what makes a belief a (...) perceptual belief, or a basic belief, is not any introspectible feature of the belief but rather the nature of the cognitive system, or "module", that is causally responsible for the belief. Thus, even zombies, who in the philosophical literature lack conscious experiences altogether, can have basic, justified, perceptual beliefs. -/- The theories of perceptual and basic beliefs developed in the monograph are embedded in a larger reliabilist epistemology. I use this theory of basic beliefs to develop a detailed reliabilist theory: Inferentialist Reliabilism, which offers a reliabilist theory of inferential justification and which solves some longstanding problems for other reliabilist views by demanding inferential support for some—but not all—beliefs. The book is an instance of a thoroughgoingly naturalistic approach to epistemology. Many of my arguments have an empirical basis, and the view that I endorse reserves a central role for the cognitive sciences—in particular, cognitive neuroscience—in filling in the details of an applied epistemological theory. (shrink)

Does metacognition--the capacity to self-evaluate one's cognitive performance--derive from a mindreading capacity, or does it rely on informational processes? Joëlle Proust draws on psychology and neuroscience to defend the second claim. She argues that metacognition need not involve metarepresentations, and is essentially related to mental agency.

One of the main goals of epistemologists is to provide a substantive and explanatory account of the conditions under which a belief has some desirable epistemic status (typically, justification or knowledge). According to the reliabilist approach to epistemology, any adequate account will need to mention the reliability of the process responsible for the belief, or truth-conducive considerations more generally. Historically, one major motivation for reliabilism—and one source of its enduring interest—is its naturalistic potential. According to reliabilists, epistemic properties can be (...) explained in terms of reliability, which in turn can be understood without reference to any unreduced epistemic notions, such as evidence or knowledge. This article begins by surveying some of the main forms of reliabilism, concentrating on process reliabilism as a theory of justification. It proceeds to review some of the main objections to reliabilism, and some of the responses that have been offered on the reliabilist’s behalf. After canvassing some recent developments in reliabilist epistemology, the article concludes by considering various cousins and spin-offs of reliabilist epistemology, including virtue reliabilism and various evidentialist-reliabilist hybrids. (shrink)

The dominant response to this problem of the criterion focuses on the alleged requirement that we need to know a belief source is reliable in order for us to acquire knowledge by that source. Let us call this requirement, “The KR principle”.

In my remarks, I discuss Sosa's attempt to deal with the sceptical threat posed by dreaming. Sosa explores two replies to the problem of dreaming scepticism. First, he argues that, on the imagination model of dreaming, dreaming does not threaten the safety of our beliefs. Second, he argues that knowledge does not require safety, but a weaker condition which is not threatened by dreaming skepticism. I raise questions about both elements of his reply.

It is tempting to think that, if a person's beliefs are coherent, they are also likely to be true. This truth conduciveness claim is the cornerstone of the popular coherence theory of knowledge and justification. Erik Olsson's new book is the most extensive and detailed study of coherence and probable truth to date. Setting new standards of precision and clarity, Olsson argues that the value of coherence has been widely overestimated. Provocative and readable, Against Coherence will make stimulating reading for (...) epistemologists and anyone with a serious interest in truth. (shrink)

According to Bayesian confirmation theory, evidence E (incrementally) confirms (or supports) a hypothesis H (roughly) just in case E and H are positively probabilistically correlated (under an appropriate probability function Pr). There are many logically equivalent ways of saying that E and H are correlated under Pr. Surprisingly, this leads to a plethora of non-equivalent quantitative measures of the degree to which E confirms H (under Pr). In fact, many non-equivalent Bayesian measures of the degree to which E confirms (or (...) supports) H have been proposed and defended in the literature on inductive logic. I provide a thorough historical survey of the various proposals, and a detailed discussion of the philosophical ramifications of the differences between them. I argue that the set of candidate measures can be narrowed drastically by just a few intuitive and simple desiderata. In the end, I provide some novel and compelling reasons to think that the correct measure of degree of evidential support (within a Bayesian framework) is the (log) likelihood ratio. The central analyses of this research have had some useful and interesting byproducts, including: (i ) a new Bayesian account of (confirmationally) independent evidence, which has applications to several important problems in con- firmation theory, including the problem of the (confirmational) value of evidential diversity, and (ii ) novel resolutions of several problems in Bayesian confirmation theory, motivated by the use of the (log) likelihood ratio measure, including a reply to the Popper-Miller critique of probabilistic induction, and a new analysis and resolution of the problem of irrelevant conjunction (a.k.a., the tacking problem). (shrink)

The reference class problem arises when we want to assign a probability to a proposition (or sentence, or event) X, which may be classified in various ways, yet its probability can change depending on how it is classified. The problem is usually regarded as one specifically for the frequentist interpretation of probability and is often considered fatal to it. I argue that versions of the classical, logical, propensity and subjectivist interpretations also fall prey to their own variants of the reference (...) class problem. Other versions of these interpretations apparently evade the problem. But I contend that they are all “no-theory” theories of probability - accounts that leave quite obscure why probability should function as a guide to life, a suitable basis for rational inference and action. The reference class problem besets those theories that are genuinely informative and that plausibly constrain our inductive reasonings and decisions. I distinguish a “metaphysical” and an “epistemological” reference class problem. I submit that we can dissolve the former problem by recognizing that probability is fundamentally a two-place notion: conditional probability is the proper primitive of probability theory. However, I concede that the epistemological problem remains. (shrink)

Let E be a set of n propositions E1, ..., En. We seek a probabilistic measure C(E) of the ‘degree of coherence’ of E. Intuitively, we want C to be a quantitative, probabilistic generalization of the (deductive) logical coherence of E. So, in particular, we require C to satisfy the following..

One attractive feature of process reliabilism is its reductive potential: it promises to explain justification in entirely non-epistemic terms. In this paper, I argue that the phenomenon of epistemic defeat poses a serious challenge for process reliabilism’s reductive ambitions. The standard process reliabilist analysis of defeat is the ‘Alternative Reliable Process Account’ (ARP). According to ARP, whether S’s belief is defeated depends on whether S has certain reliable processes available to her which, if they had been used, would have resulted (...) in S not holding the belief in question. Unfortunately, ARP proves untenable. I show, by way of counterexample, that ARP fails to articulate either necessary or sufficient conditions on defeat. Process reliabilists must either provide an alternative reductive account of defeat or renounce their reductive aspirations. (shrink)

We wish to give a precise formulation of the intuitive concept: The degree to which the known facts support a given hypothesis.

The bootstrapping problem poses a general challenge, afflicting even strongly internalist theories. Even if one must always know that one’s source is reliable to gain knowledge from it, bootstrapping is still possible. I survey some solutions internalists might offer and defend the one I find most plausible: that bootstrapping involves an abuse of inductive reasoning akin to generalizing from a small or biased sample. I also argue that this solution is equally available to the reliabilist. The moral is that the (...) issues raised by bootstrapping are orthogonal to questions about internalism and basic knowledge, having more to do with the nature of good inductive reasoning. (shrink)

* Editor’s Note: This paper won the Young Epistemologist Prize for the Rutgers Epistemology conference held in 2003.

In recent years, virtue epistemology has won the attention of a wide range of philosophers. A developed form of the position has been expounded forcefully by Ernest Sosa and represents the most plausible version of reliabilism to date. Through the person of Alvin Plantinga, virtue epistemology has taken philosophy of religion by storm, evoking objections and defenses in a wide variety of journals and volumes. Historically, virtue epistemology has its roots in the work of Thomas Reid, and the explosion of (...) Reid scholarship in the last few years is perhaps both a cause and an effect of recent interest in the position.In this paper I want to examine the virtues and vices of virtue epistemology. My conclusion will be that the position is correct, when qualified appropriately. The central claim of virtue epistemology is that, Gettier problems aside, knowledge is true belief which results from a cognitive virtue. In section one I will clarify this claim with some brief remarks about the nature of virtues in general, and cognitive virtues in particular. In section two I will consider two objections to the theory of knowledge which results. In section three of the paper I will argue that virtue epistemology can be qualified so as to avoid the objections raised in section two. Finally, I will argue that the amendments which solve the objections of section two also allow us to solve a version of the dreaded generality problem. (shrink)

What bothers people about reliabilism as a theory of justified belief? It has yet to be formulated adequately, but most philosophical theories have that problem. People seem to be bothered by the very idea of reliabilism, with its apparent disregard for believers’ rationality and responsibility. Yet its supporters can’t seem to understand its opponents complaints. I believe that the conflict can be clarified, if not resolved, by drawing certain important distinctions.

The generality problem is widely considered to be a devastating objection to reliabilist theories of justification. My goal in this paper is to argue that a version of the generality problem applies to all plausible theories of justification. Assume that any plausible theory must allow for the possibility of reflective justification—S's belief, B, is justified on the basis of S's knowledge that she arrived at B as a result of a highly (but not perfectly) reliable way of reasoning, R. The (...) generality problem applies to all cases of reflective justification: Given that is the product of a process-token that is an instance of indefinitely many belief-forming process-types (or BFPTs), why is the reliability of R, rather than the reliability of one of the indefinitely many other BFPTs, relevant to B's justificatory status? This form of the generality problem is restricted because it applies only to cases of reflective justification. But unless it is solved, the generality problem haunts all plausible theories of justification, not just reliabilist ones. (shrink)