Change in View offers an entirely original approach to the philosophical study of reasoning by identifying principles of reasoning with principles for revising one's beliefs and intentions and not with principles of logic. This crucial observation leads to a number of important and interesting consequences that impinge on psychology and artificial intelligence as well as on various branches of philosophy, from epistemology to ethics and action theory. Gilbert Harman is Professor of Philosophy at Princeton University. A Bradford Book.

" In a book that seeks to shift the ground of debate within theory of knowledge, William P. Alston finds that the century-lo.

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

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)

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 new edition of the classic Contemporary Theories of Knowledge has been significantly updated to include analyses of the recent literature in epistemology.

For most of their respective existences, reliabilism and evidentialism (that is, process reliabilism and mentalist evidentialism) have been rivals. They are generally viewed as incompatible, even antithetical, theories of justification.1 But a few people are beginning to re-think this notion. Perhaps an ideal theory would be a hybrid of the two, combining the best elements of each theory. Juan Comesana (forthcoming) takes this point of view and constructs a position called “Evidentialist Reliabilism.” He tries to show how each theory can (...) profit by borrowing elements from the other. Comesana concentrates on reliabilism’s problems and how it might be improved by infusions from evidentialism. This paper follows a similar tack. My emphasis, however, is the reverse of Comesana’s. I highlight problems for evidentialism and show how it could benefit by incorporating reliabilist themes. I am not sanguine that evidentialists will see it my way. They might even view my proposals as an insidious attempt to convert evidentialists to reliabilism. Well, I won’t debate the best way to formulate this paper’s recipe. At any rate, it began with the idea (which anteceded my reading of Comesana) of creating a synthesis of reliabilism and evidentialism. It retains significant strands of that idea, although the synthesis theme does not pervade the entire paper. What is mentalist evidentialism? Its original formulation was succinct. (shrink)

I have been supposing that for the theory of reasoning, explicit belief is an all-or-nothing matter, I have assumed that, as far as principles of reasoning are concerned, one either believes something explicitly or one does not; in other words an appropriate "representation" is either in one's "memory" or not. The principles of reasoning are principles for modifying such all-or-nothing representations. This is not to deny that in some ways belief is a matter of degree. For one thing implicit belief (...) is certainly a matter of degree, since it is a matter of how easily and automatically one can infer something from what one believes explicitly. Furthermore, explicit belief is a matter of degree in the sense that one believes some things more strongly than others. Sometimes one is only somewhat inclined to believe something, sometimes one is not sure what to believe, sometimes one is inclined to disbelieve something, sometimes one is quite confident something is not so, and so forth. (shrink)

It is often said, metaphorically, that belief "aims" at the truth. This paper proposes a normative interpretation of this metaphor. First, the notion of "epistemic norms" is clarified, and reasons are given for the view that epistemic norms articulate essential features of the beliefs that are subject to them. Then it is argued that all epistemic norms--including those that specify when beliefs count as rational, and when they count as knowledge--are explained by a fundamental norm of correct belief, which requires (...) that, if one considers a proposition at all, one should believe it if and only if it is true. (shrink)

Reliabilists hold that a belief is doxastically justified if and only if it is caused by a reliable process. But since such a process is one that tends to produce a high ratio of true to false beliefs, reliabilism is on the face of it applicable to binary beliefs, but not to degrees of confidence or credences. For while beliefs admit of truth or falsity, the same cannot be said of credences in general. A natural question now arises: Can reliability (...) theories of justified belief be extended or modified to account for justified credence? In this paper, I address this question. I begin by showing that, as it stands, reliabilism cannot account for justified credence. I then consider three ways in which the reliabilist may try to do so by extending or modifying her theory, but I argue that such attempts face certain problems. After that, I turn to a version of reliabilism that incorporates evidentialist elements and argue that it allows us to avoid the problems that the other theories face. If I am right, this gives reliabilists a reason, aside from those given recently by Comesaña and Goldman, to move towards such a kind of hybrid theory. (shrink)

The objective of this book is to produce a theory of rational decision making for realistically resource-bounded agents. My interest is not in “What should I do if I were an ideal agent?”, but rather, “What should I do given that I am who I am, with all my actual cognitive limitations?” The book has three parts. Part One addresses the question of where the values come from that agents use in rational decision making. The most comon view among philosophers (...) is that they are based on preferences, but I argue that this is computationally impossible. I propose an alternative theory somewhat reminiscent of Bentham, and explore how human beings actually arrive at values and how they use them in decision making. Part Two investigates the knowledge of probability that is required for decision-theoretic reasoning. I argue that subjective probability makes no sense as applied to realistic agents. I sketch a theory of objective probability to put in its place. Then I use that to define a variety of causal probability and argue that this is the kind of probability presupposed by rational decision making. So what is to be defended is a variety of causal decision theory. Part Three explores how these values and probabilities are to be used in decision making. In chapter eight, it is argued first that actions cannot be evaluated in terms of their expected values as ordinarily defined, because that does not take account of the fact that a cognizer may be unable to perform an action, and may even be unable to try to perform it. An alternative notion of “expected utility” is defined to be used in place of expected values. In chapter nine it is argued that individual actions cannot be the proper objects of decision-theoretic evaluation. We must instead choose plans, and select actions indirectly on the grounds that they are prescribed by the plans we adopt. However, our objective cannot be to find plans with maximal expected utilities. Plans cannot be meaningfully compared in that way. (shrink)

This paper considers two questions. First, what is the scope of the Equal Weight View? Is it the case that meeting halfway is the uniquely rational method of belief-revision in all cases of known peer disagreement? The answer is no. It is sometimes rational to maintain your own opinion in the face of peer disagreement. But this leaves open the possibility that the Equal Weight View is indeed sometimes the uniquely rational method of belief revision. Precisely what is the skeptical (...) import of this fact; is it the case that some form of skepticism triumphs in such cases? The answer to this question is also no. As it turns out, the situations in which it is most plausible that the Equal Weight view is a rational requirement are the ones in which meeting halfway with a disagreeing peer brings you closer to, and not farther from, knowledge. I argue for these theses in a novel way; by looking at the comparative reliability of belief- invariance and meeting halfway using measures of reliability for degrees of belief, and by drawing normative conclusions from such results. The conclusions here can have the effect of reframing the entire debate in the epistemology of disagreement. (shrink)

The pragmatic character of the Dutch book argument makes it unsuitable as an "epistemic" justification for the fundamental probabilist dogma that rational partial beliefs must conform to the axioms of probability. To secure an appropriately epistemic justification for this conclusion, one must explain what it means for a system of partial beliefs to accurately represent the state of the world, and then show that partial beliefs that violate the laws of probability are invariably less accurate than they could be otherwise. (...) The first task can be accomplished once we realize that the accuracy of systems of partial beliefs can be measured on a gradational scale that satisfies a small set of formal constraints, each of which has a sound epistemic motivation. When accuracy is measured in this way it can be shown that any system of degrees of belief that violates the axioms of probability can be replaced by an alternative system that obeys the axioms and yet is more accurate in every possible world. Since epistemically rational agents must strive to hold accurate beliefs, this establishes conformity with the axioms of probability as a norm of epistemic rationality whatever its prudential merits or defects might be. (shrink)

Abstract In this paper I undertake an in-depth examination of an oft mentioned but rarely expounded upon state: suspended judgment. While traditional epistemology is sometimes characterized as presenting a “yes or no” picture of its central attitudes, in fact many of these epistemologists want to say that there is a third option: subjects can also suspend judgment. Discussions of suspension are mostly brief and have been less than clear on a number of issues, in particular whether this third option should (...) be thought of as an attitude or not. In this paper I argue that suspended judgment is (or at least involves) a genuine attitude. Content Type Journal Article Pages 1-17 DOI 10.1007/s11098-011-9753-y Authors Jane Friedman, St Catherine’s College, University of Oxford, Oxford, OX1 3UJ UK Journal Philosophical Studies Online ISSN 1573-0883 Print ISSN 0031-8116. (shrink)

Evidentialism is a view about the conditions under which a person is epistemically justified in having a particular doxastic attitude toward a proposition. Evidentialism holds that the justified attitudes are determined entirely by the person's evidence. This is the traditional view of justification. It is now widely opposed. The essays included in this volume develop and defend the tradition.Evidentialism has many assets. In addition to providing an intuitively plausible account of epistemic justification, it helps to resolve the problem of the (...) criterion, helps to disentangle epistemic and ethical evaluations, and illuminates the relationship between epistemic evaluations of beliefs and the evaluation of the methods used to form beliefs. These issues are all addressed in the essays presented here. External world skepticism poses the classic problem for an epistemological theory. The final essay in this volume argues that evidentialism is uniquely well qualified to make sense of skepticism and to respond to its challenge.Evidentialism is a version of epistemic internalism. Recent epistemology has included many attacks on internalism and has seen the development of numerous externalist theories. The essays included here respond to those attacks and raise objections to externalist theories, especially the principal rival, reliabilism. Internalism generally has been criticized for having unacceptable deontological implications, for failing to connect epistemic justification to truth, and for failing to provide an adequate account of what makes basic beliefs justified. Each of these charges is answered in these essays. The collection includes two previously unpublished essays and new afterwords to five of the reprinted essays; it will be the definitive resource on evidentialism for all epistemologists. (shrink)

In this paper, I respond to recent attempts by philosophers to deny the existence of something that is both real and significant: reasonable disagreements between epistemic peers. In their arguments against the possibility of such disagreements, skeptical philosophers typically invoke one or more of the following: indifference reasoning , equal weight principles , and uniqueness theses . I take up each of these in turn, finding ample reason to resist them. The arguments for indifference reasoning and equal weight principles tend (...) to overlook the possibility of a certain kind of agnostic credal state which I call deep agnosticism , the possibility of which derails the arguments. The arguments for uniqueness theses tend to invoke a flawed understanding of the evidential support relation. When these problems and misunderstandings are brought into the light and corrected, the threat to reasonable disagreement vanishes. (shrink)

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.

Pollock argues that theories of ideal rationality are largely irrelevant to the decision making of real agents. Thinking about Acting aims to provide a theory of "real rationality.".

How can we know? How can we attain justified belief? These traditional questions in epistemology have inspired philosophers for centuries. Now, in this exceptional work, Alvin Goldman, distinguished scholar and leader in the fields of epistemology and mind, approaches such inquiries as legitimate methods or "pathways" to knowledge. He examines the notion of private and public knowledge, arguing for the epistemic legitimacy of private and introspective methods of gaining knowledge, yet acknowledging the equal importance of social and public mechanisms in (...) the quest for truth. Throughout, he addresses this opposition but proposes a rigorous framework that continues to resolve such contradictions, making this exciting text one of the most important contributions to the theory of knowledge in recent years. (shrink)

There is a duality in our everyday view of belief. On the one hand, we sometimes speak of credence as a matter of degree. We talk of having some level of confidence in a claim (that a certain course of action is safe, for example, or that a desired event will occur) and explain our actions by reference to these degrees of confidence – tacitly appealing, it seems, to a probabilistic calculus such as that formalized in Bayesian decision theory. On (...) the other hand, we also speak of belief as an unqualified, or flat-out, state (‘plain belief’ as it is sometimes called), which is either categorically present or categorically absent. We talk of simply believing or thinking that something is the case, and we cite these flat-out attitudes in explanation of our actions – appealing to classical practical reasoning of the sort formalized in the so-called ‘practical syllogism’.1 This tension in everyday discourse is reflected in the theoretical literature on belief. In formal epistemology there is a division between those in the Bayesian tradition, who treat credence as graded, and those who think of it as a categorical attitude of some kind. The Bayesian perspective also contrasts with the dominant view in philosophy of mind, where belief is widely regarded as a categorical state (a token sentence of a mental language, inscribed in a functionally defined ‘belief box’, according to one popular account). A parallel duality is present in our everyday view of desire. Sometimes we talk of having degrees of preference or desirability; sometimes we speak simply of wanting or desiring something tout court, and, again, this tension is reflected in the theoretical literature. What should we make of these dualities? Are there two different types of belief and desire – partial and flat-out, as they are sometimes called? If so, how are they related? And how could both have a role in guiding rational action, as the everyday view has it? The last question poses a particular challenge in relation to flat-out belief and desire.. (shrink)