In this important new text, Keith Lehrer introduces students to the major traditional and contemporary accounts of knowing. Beginning with the accepted 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, externalism and naturalized epistemologies, internalism and modern coherence theories as well as recent reliabilist and causal theories. Lehrer gives all views careful examination and concludes that external factors must be matched by (...) appropriate internal ones to yield knowledge. Readers of Professor Lehrer's earlier book _Knowledge_ will want to know that this text adopts the framework of that classic text. But _Theory of Knowledge_ is a completely rewritten and updated version of that book that has been simplified throughout for student use. (shrink)

Paul Moser's book defends what has been an unfashionable view in recent epistemology: the foundationalist account of knowledge and justification. Since the time of Plato philosophers have wondered what exactly knowledge is. This book develops a new account of perceptual knowledge which specifies the exact sense in which knowledge has foundations. The author argues that experiential foundations are indeed essential to perceptual knowledge, and he explains what knowledge requires beyond justified true beliefs. In challenging prominent sceptical claims that we have (...) no justified beliefs about the external world, the book outlines a theory of rational belief. (shrink)

I defend the acceptance principle for testimony (APT), that hearers are justified in accepting testimony unless they have positive evidence against its reliability, against Elizabeth Fricker's local reductionist view. Local reductionism, the doctrine that hearers need evidence that a particular piece of testimony is reliable if they are to be justified in believing it, must on pain of scepticism be complemented by a principle that grants default justification to some testimony; I argue that (APT) is the principle required. I consider (...) two alternative weaker principles as complements to local reductionism; one yields counter-intuitive results unless we accept (APT) as well, while the other is too weak to enable local reductionism to avoid scepticism. (shrink)

We citizens of the 21st century live in a world where division of epistemic labour rules. Most of what we know we learned from the spoken or written word of others, and we depend in endless practical ways on the technological fruits of the dispersed knowledge of others—of which we often know almost nothing—in virtually every moment of our lives. Interest has been growing in recent years amongst philosophers, in the issues in epistemology raised by this fact. One issue concerns (...) the depth and extent of our epistemic dependence on testimony, as we may label this broad epistemic source: Do we have any knowledge at all that is free of epistemic dependence on what we have learned from others? A related question is whether our entitlement to believe what we have learned from others can be explained without invoking any epistemic principles special to testimony. These questions concern, as it were, the macro-epistemology of testimony. In the present discussion I shall focus instead on the micro foundations. Testimony, in our broad sense, can occur through an extensive range of types of spoken and written means of purportedly factual communication, including telephone calls, e-mails and personal letters, lectures and radio broadcasts, newspapers, textbooks and encyclopaedias, personal diaries, and public records of all kinds. But the central paradigm—what started the whole communication thing off—is surely that of face-to-face spoken encounter, when one person tells something to another, thereby intending and hoping to share her knowledge with her audience. I begin by describing the speech act of telling, identifying what takes place in a felicitous act of telling. From the nature of the speech act of telling, we see precisely how it is that knowledge is, when all goes as it should, acquired from teller by trusting hearer, in such an act, and in acts of testimony more broadly. (shrink)

We often talk about knowledge being transmitted via testimony. This suggests a picture of testimony with striking similarities to memory. For instance, it is often assumed that neither is a generative source of knowledge: while the former transmits knowledge from one speaker to another, the latter preserves beliefs from one time to another. These considerations give rise to a stronger and a weaker thesis regarding the transmission of testimonial knowledge. The stronger thesis is that each speaker in a chain of (...) testimonial transmission must know that p in order to pass this knowledge to a hearer. The weaker thesis is that at least the first speaker must know that p in order for any hearer in the chain to come to know that p via testimony. I argue that both theses are false, and hence testimony, unlike memory, can be a generative source of knowledge. (shrink)

I defend the acceptance principle for testimony (APT), that hearers are justified in accepting testimony unless they have positive evidence against its reliability, against Elizabeth Fricker's local reductionist view. Local reductionism, the doctrine that hearers need evidence that a particular piece of testimony is reliable if they are to be justified in believing it, must on pain of scepticism be complemented by a principle that grants default justification to some testimony; I argue that (APT) is the principle required. I consider (...) two alternative weaker principles as complements to local reductionism; one yields counter-intuitive results unless we accept (APT) as well, while the other is too weak to enable local reductionism to avoid scepticism. (shrink)

This target article presents a new computational theory of explanatory coherence that applies to the acceptance and rejection of scientific hypotheses as well as to reasoning in everyday life, The theory consists of seven principles that establish relations of local coherence between a hypothesis and other propositions. A hypothesis coheres with propositions that it explains, or that explain it, or that participate with it in explaining other propositions, or that offer analogous explanations. Propositions are incoherent with each other if they (...) are contradictory, Propositions that describe the results of observation have a degree of acceptability on their own. An explanatory hypothesis is acccpted if it coheres better overall than its competitors. The power of the seven principles is shown by their implementation in a connectionist program called ECHO, which treats hypothesis evaluation as a constraint satisfaction problem. Inputs about the explanatory relations are used to create a network of units representing propositions, while coherende and incoherence relations are encoded by excitatory and inbihitory links. ECHO provides an algorithm for smoothly integrating theory evaluation based on considerations of explanatory breadth, simplicity, and analogy. It has been applied to such important scientific cases as Lovoisier's argument for oxygen against the phlogiston theory and Darwin's argument for evolution against creationism, and also to cases of legal reasoning. The theory of explanatory coherence has implications for artificial intelligence, psychology, and philosophy. (shrink)

This article is a response to Elijah Millgram's argument that my characterization of coherence as constraint satisfaction is inadequate for philosophical purposes because it provides no guarantee that the most coherent theory available will be true. I argue that the constraint satisfaction account of coherence satisfies the philosophical, computational, and psychological prerequisites for the development of epistemological and ethical theories.

The basic alternatives seem to be either a Humean reductionist view that any particular assertion needs backing with inductive evidence for its reliability before it can retionally be believed, or a Reidian criterial view that testimony is intrinscially, though defeasibly, credible, in the absence of evidence against its reliability.Some recent arguments from the constraints on interpreting any linguistic performances as assertions with propositional content have some force against the reductionist view. We thus have reason to accept the criterial view, at (...) least as applied to eyewitness reports. But these considerations do not establish that any rational enquirer must have the concept of other minds or testimony. The logical possibility of the lone enquirer, who uses symbols and thereby expresses some knowledge of his world, remains open — but it is a question we have no need to pronounce upon. (shrink)

One of the central points of contention in the epistemology of testimony concerns the uniqueness (or not) of the justification of beliefs formed through testimony--whether such justification can be accounted for in terms of, or 'reduced to,' other familiar sort of justification, e.g. without relying on any epistemic principles unique to testimony. One influential argument for the reductionist position, found in the work of Elizabeth Fricker, argues by appeal to the need for the hearer to monitor the testimony for credibility. (...) Fricker (1994) argues, first, that some monitoring for trustworthiness is required if the hearer is to avoid being gullible, and second, that reductionism but not anti-reductionism is compatible with ascribing an important role to the process of monitoring in the course of justifiably accepting observed testimony. In this paper we argue that such an argument fails. (shrink)

What is the relation between coherence and truth? This paper rejects numerous answers to this question, including the following: truth is coherence; coherence is irrelevant to truth; coherence always leads to truth; coherence leads to probability, which leads to truth. I will argue that coherence of the right kind leads to at least approximate truth. The right kind is explanatory coherence, where explanation consists in describing mechanisms. We can judge that a scientific theory is progressively approximating the truth if it (...) is increasing its explanatory coherence in two key respects: broadening by explaining more phenomena and deepening by investigating layers of mechanisms. I sketch an explanation of why deepening is a good epistemic strategy and discuss the prospect of deepening knowledge in the social sciences and everyday life. (shrink)

Although there is widespread agreement that our epistemic dependence on other people's knowledge is a key ingredient of our cognitive life, the role of trust in this dependence is much more open to debate. Is trust in epistemic authority—or “epistemic trust” for short—an epistemological notion in any sense, or is it simply a bridge-concept that connects our epistemological concerns to moral issues? Should we depict it in terms of the more familiar sociological notion of trust as a basis for cooperation?

We monitor the informational environment and catch reputational cues, gather signals from our informants and develop our trustful attitudes in context. I present an epistemology of reputation as a way of using social configurations to acquire information. I review the definitions of reputation that exist in the social sciences, stress the importance of the relational/social dimension of reputation as a property of entities, and put forward a definition of reputation suitable for epistemology. I then sketch social configurations that allow us (...) to extract reputational information and some typical heuristics we use to navigate the social information around us. (shrink)

Paul Moser's book defends what has been an unfashionable view in recent epistemology: the foundationalist account of knowledge and justification. Since the time of Plato philosophers have wondered what exactly knowledge is. This book develops a new account of perceptual knowledge which specifies the exact sense in which knowledge has foundations. The author argues that experiential foundations are indeed essential to perceptual knowledge, and he explains what knowledge requires beyond justified true beliefs. In challenging prominent sceptical claims that we have (...) no justified beliefs about the external world, the book outlines a theory of rational belief. (shrink)

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)

We often talk about knowledge being transmitted via testimony. This suggests a picture of testimony with striking similarities to memory. For instance, it is often assumed that neither is a generative source of knowledge: while the former transmits knowledge from one speaker to another, the latter preserves beliefs from one time to another. These considerations give rise to a stronger and a weaker thesis regarding the transmission of testimonial knowledge. The stronger thesis is that each speaker in a chain of (...) testimonial transmission must know that p in order to pass this knowledge to a hearer. The weaker thesis is that at least the first speaker must know that p in order for any hearer in the chain to come to know that p via testimony. I argue that both theses are false, and hence testimony, unlike memory, can be a generative source of knowledge. (shrink)

During the last three decades, reflections on the growth of scientific knowledge have inspired historians, sociologists, and some philosophers to contend that scientific objectivity is a myth. In this book, Kitcher attempts to resurrect the notions of objectivity and progress in science by identifying both the limitations of idealized treatments of growth of knowledge and the overreactions to philosophical idealizations. Recognizing that science is done not by logically omniscient subjects working in isolation, but by people with a variety of personal (...) and social interests, who cooperate and compete with one another, he argues that, nonetheless, we may conceive the growth of science as a process in which both our vision of nature and our ways of learning more about nature improve. Offering a detailed picture of the advancement of science, he sets a new agenda for the philosophy of science and for other "science studies" disciplines. (shrink)

Thoughts and other mental states are defined by their role in a functional system. Since it is easier to determine when we have knowledge than when reasoning has occurred, Gilbert Harman attempts to answer the latter question by seeing what assumptions about reasoning would best account for when we have knowledge and when not. He describes induction as inference to the best explanation, or more precisely as a modification of beliefs that seeks to minimize change and maximize explanatory coherence. Originally (...) published in 1973. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905. (shrink)

Our folk epistemology says that if someone knows that P and tells you that P, then, given the absence of defeaters, if you believe what they tell you, you will come to know that P as well. A speaker's knowledge that P is then, for the most part, enough for a hearer to come to know that P. But there are counterexamples to this principle: testimonial knowledge does not always transfer from the speaker to the hearer. Why should that be (...) so? Because testimonial knowledge arises through the flow of information--from conclusive grounds--from the speaker through the speaker's assertion to the hearer's state of comprehension as of the speaker's assertion. A speaker's belief can be based on conclusive grounds, but the speaker's assertion may fail to provide conclusive grounds to the hearer. Then the hearer won't acquire knowledge, even from a knowledgeable speaker. Knowledge from testimony then works more like knowledge through perception. But wait, you say, that can't be so because testimony involves free will but perception does not. The essay ends with a broadly Hume inspired reply to this objection. (shrink)

Jennifer Lackey ('Testimonial Knowledge and Transmission' The Philosophical Quarterly 1999) and Peter Graham ('Conveying Information, Synthese 2000, 'Transferring Knowledge' Nous 2000) offered counterexamples to show that a hearer can acquire knowledge that P from a speaker who asserts that P, but the speaker does not know that P. These examples suggest testimony can generate knowledge. The showpiece of Lackey's examples is the Schoolteacher case. This paper shows that Lackey's case does not undermine the orthodox view that testimony cannot generate knowledge. (...) This paper explains why Lackey's arguments to the contrary are ineffective for they misunderstand the intuitive rationale for the view that testimony cannot generate knowledge. This paper then elaborates on a version of the case from Graham's paper 'Conveying Information' (the Fossil case) that effectively shows that testimony can generate knowledge. This paper then provides a deeper informative explanation for how it is that testimony transfers knowledge, and why there should be cases where testimony generates knowledge. (shrink)

This paper states three counterexamples to the claim that testimony cannot generate knowledge, that a hearer can only acquire testimonial knowledge from a speaker who knows: a twins case, the fossil case, and an inversion case. The paper provides an explanation for why testimony can generate knowledge. Testimonial knowledge involves the flow of information from a speaker to a hearer through the linguistic channel.

Knowledge in a Social World offers a philosophy for the information age. Alvin Goldman explores new frontiers by creating a thoroughgoing social epistemology, moving beyond the traditional focus on solitary knowers. Against the tides of postmodernism and social constructionism Goldman defends the integrity of truth and shows how to promote it by well-designed forms of social interaction. From science to education, from law to democracy, he shows why and how public institutions should seek knowledge-enhancing practices. The result is a bold, (...) timely, and systematic treatment of the philosophical foundations of an information society. (shrink)

Rumors, for better or worse, are an important element of public discourse. The present paper focuses on rumors as an epistemic phenomenon rather than as a social or political problem. In particular, it investigates the relation between the mode of transmission and the reliability, if any, of rumors as a source of knowledge. It does so by comparing rumor with two forms of epistemic dependence that have recently received attention in the philosophical literature: our dependence on the testimony of others, (...) and our dependence on what has been called the ‘coverage-reliability’ of our social environment (Goldberg 2010). According to the latter, an environment is ‘coverage-reliable’ if, across a wide range of beliefs and given certain conditions, it supports the following conditional: If ~p were true I would have heard about it by now. However, in information-deprived social environments with little coverage-reliability, rumors may transmit information that could not otherwise be had. This suggests that a trade-off exists between levels of trust in the coverage-reliability of official sources and (warranted) trust in rumor as a source of information. (shrink)

Not limited to merely mathematics, probability has a rich and controversial philosophical aspect. _A Philosophical Introduction to Probability_ showcases lesser-known philosophical notions of probability and explores the debate over their interpretations. Galavotti traces the history of probability and its mathematical properties and then discusses various philosophical positions on probability, from the Pierre Simon de Laplace's “classical” interpretation of probability to the logical interpretation proposed by John Maynard Keynes. This book is a valuable resource for students in philosophy and mathematics and (...) all readers interested in notions of probability. (shrink)

Coady’s book is probably the single most comprehensive treatment of philosophical questions relating to testimony and as such must be read by anyone interested in the topic. His epistemological conclusions concerning testimony challenge much of the philosophical tradition.

Testimony is indispensable in the sciences. To deny the propriety of relying on it engenders an untenable scepticism. But this leaves open the issue of what exactly confers a scientist’s epistemic right to rely upon the word of her colleagues. Some authors have suggested a recipient of testimony enjoys an epistemic entitlement to trust the word of another as such, not requiring evidence of her trustworthiness, so long as there is not evidence of her untrustworthiness. I argue that, whether or (...) not such an on-no-evidence entitlement to believe what one is told exists, it shrinks to irrelevance in the explanation of the basis on which scientists take each other’s word in the scientific community. This is so, since a normally knowledgeable adult hearer is typically awash with relevant evidence, direct and circumstantial, for and against, concerning a teller’s trustworthiness, and this swamps any alleged entitlement to believe in the absence of such evidence. There need not be personal knowledge of the teller, since social role and topic provide evidence regarding trustworthiness. I also discuss the individuation of ‘testimony’ as an epistemic kind. I suggest that we should not attempt to define a category with sharp boundaries, but instead characterise a paradigm case—one person telling another something in face-to-face personal communication—and then notice other cases which both resemble and diverge from this in epistemically relevant features—lectures, media broadcasts, personal letters, personal diaries, etc.Author Keywords: Testimony; Justification; Knowledge; Individualism; Communication. (shrink)

We citizens of the 21st century live in a world where division of epistemic labour rules. Most of what we know we learned from the spoken or written word of others, and we depend in endless practical ways on the technological fruits of the dispersed knowledge of others—of which we often know almost nothing—in virtually every moment of our lives. Interest has been growing in recent years amongst philosophers, in the issues in epistemology raised by this fact. One issue concerns (...) the depth and extent of our epistemic dependence on testimony, as we may label this broad epistemic source: Do we have any knowledge at all that is free of epistemic dependence on what we have learned from others? A related question is whether our entitlement to believe what we have learned from others can be explained without invoking any epistemic principles special to testimony. These questions concern, as it were, the macro-epistemology of testimony. In the present discussion I shall focus instead on the micro foundations. Testimony, in our broad sense, can occur through an extensive range of types of spoken and written means of purportedly factual communication, including telephone calls, e-mails and personal letters, lectures and radio broadcasts, newspapers, textbooks and encyclopaedias, personal diaries, and public records of all kinds. But the central paradigm—what started the whole communication thing off—is surely that of face-to-face spoken encounter, when one person tells something to another, thereby intending and hoping to share her knowledge with her audience. I begin by describing the speech act of telling, identifying what takes place in a felicitous act of telling. From the nature of the speech act of telling, we see precisely how it is that knowledge is, when all goes as it should, acquired from teller by trusting hearer, in such an act, and in acts of testimony more broadly. (shrink)

David Hume advances a reductionist epistemology of testimony: testimonial beliefs are justified on the basis of beliefs formed from other sources. This reduction, however, has been misunderstood. Testimonial beliefs are not justified in a manner identical to ordinary empirical beliefs; it is true, they are justified by observation of the conjunction between testimony and its truth, it is the nature of the conjunctions that has been misunderstood. The observation of these conjunctions provides us with our knowledge of human nature and (...) it is this knowledge which justifies our testimonial beliefs. Hume gives a naturalistic rather than sceptical account of testimony. (shrink)

Our trust in the word of others is often dismissed as unworthy, because the illusory ideal of "autonomous knowledge" has prevailed in the debate about the nature of knowledge. Yet we are profoundly dependent on others for a vast amount of what any of us claim to know. Coady explores the nature of testimony in order to show how it might be justified as a source of knowledge, and uses the insights that he has developed to challenge certain widespread assumptions (...) in the areas of history, law, mathematics, and psychology. (shrink)

Bradley's metaphysical views, akin to those of Hegel, with a special emphasis on the internal relations of the Absolute are developed at length in Appearance ...

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 ...

My aim in this paper is to explore the dispute between foundationalism and coherentism and attempt a resolution. I will begin by considering the origin of the issue in the famous epistemic regress problem. Next I will explore the central foundationalist idea and the most central objections that have been raised against foundationalist views. This will lead to a consideration of the main contours of the coherentist alternative, and eventually to a discussion of objections to coherentism – including several specific (...) ones that I now judge to be clearly fatal, especially when taken together. This will motivate, finally, a reconsideration of foundationalism. I will argue that the dialectically most serious objection to foundationalism can be successfully answered. While the answer that I will suggest admittedly carries with it the price of aggravating certain other difficulties, especially the venerable problem of showing how belief in an external world of physical objects can be justified, it still seems to me to leave foundationalism as by far the more defensible and promising of the two alternatives. (shrink)