In this article I have two primary goals. First, I present two recent views on the distinction between knowledge-that and knowledge-how (Stanley and Williamson, The Journal of Philosophy 98(8):411–444, 2001; Hetherington, Epistemology futures, 2006). I contend that neither of these provides conclusive arguments against the distinction. Second, I discuss studies from neuroscience and experimental psychology that relate to this distinction. Having examined these studies, I then defend a third view that explains certain relevant data from these studies by positing the (...) double dissociation of knowledge-that and knowledge-how and that is also able to do explanatory work elsewhere. (shrink)

Original and penetrating, this book investigates of the notion of inference from signs, which played a central role in ancient philosophical and scientific method. It examines an important chapter in ancient epistemology: the debates about the nature of evidence and of the inferences based on it--or signs and sign-inferences as they were called in antiquity. As the first comprehensive treatment of this topic, it fills an important gap in the histories of science and philosophy.

provides a sustained and ambitious development of the basic idea that knowledge is true belief that tracks the truth. In this essay, I provide a quick synopsis of Roush's book and offer a substantive discussion of her analysis of scientific evidence. Roush argues that, for e to serve as evidence for h, it should be easier to determine the truth value of e than it is to determine the truth value of h, an ideal she refers to as ‘leverage’. She (...) defends a detailed method by which the value of p(h/e) is computed without ‘direct’ information about p(h) but only using evidence about the value of p(e), from which the value of p(h) is derived. She presents an example of how to use her leverage method, which I argue involves a certain critical mistake. I show how the leveraging method can be used in a way that is sound—I conclude with a few remarks about the importance of distinguishing clearly between prior and posterior probabilities. CiteULike    Connotea    Del.icio.us    What's this? (shrink)

It is no secret that scientists argue. They argue about theories. But even more, they argue about the evidence for theories. Is the evidence itself trustworthy? This is a bit surprising from the perspective of traditional empiricist accounts of scientific methodology according to which the evidence for scientific theories stems from observation, especially observation with the naked eye. These accounts portray the testing of scientific theories as a matter of comparing the predictions of the theory with the data generated by (...) these observations, which are taken to provide an objective link to reality. (shrink)

The first obstacle that confronts the student of induction is that of defining the subject matter. One initial point is to note that much of the relevant subject matter goes under the description ‘the theory of confirmation’. The distinction is primarily that the study of induction concerns inference, i.e. cases where one takes the conclusion to be established by the evidence, whereas confirmation concerns the weight of evidence, which one may take to be something like the credibility of a hypothesis (...) in the light of the evidence. Discussions of confirmation often concern incremental confirmation, i.e. cases where the evidence is taken to increase the credibility of some hypothesis, even if not sufficiently to warrant inferring the truth of that hypothesis. However, some uses of ‘confirmation’ clearly refer to absolute confirmation, cases where the credibility of the hypothesis in the light of the evidence exceeds some (high) threshold. One may ask whether inductive inference corresponds to the case of absolute confirmation for some suitable threshold. I shall discuss inference and confirmation together, though it should be noted that some approaches eschew inference altogether. For example, the Bayesian takes scientific reasoning to be a matter of adjusting credences in propositions in the light of evidence, and says nothing about unqualified belief in a proposition. However, if we are interested in inductive knowledge then we must consider inference, since only then do we have a detached proposition that is the possible content of a mental state of knowing. A more pressing question concerns which inferences (or allegedly confirmatory relations) should be classed as inductive. A natural and straightforward approach is to define induction as encompassing any form of reasoning that extrapolates from one population to another, usually from a sample of a population to the whole population. For example, one might note that all observations of the position of some planet fall on an ellipse that has the Sun at one of its foci; from this one concludes that all the positions that planet takes fall on this ellipse (i.e.. (shrink)

The usual, comparative, conception of Inference to the Best Explanation (IBE) takes it to be ampliative. In this paper I propose a conception of IBE (‘Holmesian inference’) that takes it to be a species of eliminative induction and hence not ampliative. This avoids several problems for comparative IBE (e.g. how could it be reliable enough to generate knowledge?). My account of Holmesian inference raises the suspicion that it could never be applied, on the grounds that scientific hypotheses are inevitably underdetermined (...) by the evidence (i.e. are inevitably ampliative). I argue that this concern may be resisted by acknowledging, as Timothy Williamson has shown, that all knowledge is evidence. This suggests an approach to resisting scepticism different from those (e.g. the reliabilist approach) that embrace fallibilism. (shrink)

Evidence is often taken to be foundational, in that while other propositions may be inferred from our evidence, evidence propositions are themselves not inferred from anything. I argue that this conception is false, since the non-inferential propositions on which beliefs are ultimately founded may be forgotten or undermined in the course of enquiry.

Joshua Thurow offers a defence of the claim that if a belief is defeasible by non-experiential evidence then it is defeasible by experiential evidence. He responds to an objection which I make against this claim, and offers two arguments in support of his own position. I show that Thurow's response misconstrues my objection, and that his supporting arguments fall short of their goal.

How much should your confidence in your beliefs be shaken when you learn that others – perhaps 'epistemic peers' who seem as well-qualified as you are – hold beliefs contrary to yours? This article describes motivations that push different philosophers towards opposite answers to this question. It identifies a key theoretical principle that divides current writers on the epistemology of disagreement. It then examines arguments bearing on that principle, and on the wider issue. It ends by describing some outstanding questions (...) that thinking about this issue raises. (shrink)

This paper assesses several prominent recent attacks on the view that epistemic justification is conceptually prior to knowledge. I argue that this view—call it the Received View (RV)—emerges from these attacks unscathed. I start with Timothy Williamson’s two strongest arguments for the claim that all evidence is knowledge (E>K), which impugns RV when combined with the claim that justification depends on evidence. One of Williamson’s arguments assumes a false epistemic closure principle; the other misses some alternative (to E>K) explanations of (...) a putative fact about the evidence a particular subject has. Next, I neutralize each of Jonathan Sutton’s three recent arguments to the conclusion that any justified belief constitutes knowledge. Finally, I consider a recent analysis of justification due to Alexander Bird, according to which justified belief is possible knowledge. I argue that Bird’s analysis delivers neither a sufficient nor (more importantly) a necessary condition for justification. [Word count: 149]. (shrink)

We argue that if evidence were knowledge, then there wouldn’t be any Gettier cases, and justification would fail to be closed in egregious ways. But there are Gettier cases, and justification does not fail to be close in egregious ways. Therefore, evidence isn’t knowledge.

The coherence of the whole truth is a presupposition of any holistic coherence theory of justification that postulates a positive connection between justification and truth, for unless the whole truth is itself systemically coherent there is no reason to look for systemic coherence when deciding whether one is justified in accepting a given body of beliefs as true. This paper develops a formal model of holistic evidential coherence and uses this model to formalize and defend the claim that the whole (...) truth must be coherent in an evidential sense. (shrink)

Bayesian epistemology postulates a probabilistic analysis of many sorts of ordinary and scientific reasoning. Huber ([2005]) has provided a novel criticism of Bayesianism, whose core argument involves a challenging issue: confirmation by uncertain evidence. In this paper, we argue that under a properly defined Bayesian account of confirmation by uncertain evidence, Huber's criticism fails. By contrast, our discussion will highlight what we take as some new and appealing features of Bayesian confirmation theory. Introduction Uncertain Evidence and Bayesian Confirmation Bayesian Confirmation (...) by Uncertain Evidence: Test Cases and Basic Principles CiteULike Connotea Del.icio.us What's this? (shrink)

J. David Velleman casts foreknowledge of one's own next move as psychologically active. As agents, we form prior intentions about what we will do next. Such prior intentions are licensed self-fulfilling beliefs or directive cognitions. These cognitions differ from ordinary predictions in their psychological relation to the evidence, in that they precede that crucial part of the evidence which consists in the fact that they have been formed. However, once formed, these cognitions are epistemologically unremarkable: they are directly justified by (...) evidence, which saliently includes the fact of their own existence. I argue that Velleman distorts both the epistemology and the etiology of self-knowing agency. Self-knowing agents typically know what they will do next non-evidentially, and yet their knowledge of their own next move is formed in response to their (perspective-relative) epistemic grounds. Velleman's account of self-knowing agency is doubly distortive because it ignores the role of the purely first-person point of view which typically characterizes such agency. In developing an alternative account of self-knowing agency, I argue that the kind of knowledge that we typically have of what we are about to do is like the kind of knowledge we have when we non-evidentially know what our own current, conscious propositional thoughts are. We can non-evidentially know what we think in virtue of having made up our minds what to think. Likewise, we can non-evidentially know what we are about to do in virtue of having settled on what to do next. (shrink)

George Bealer argues that intuitions are not only reliable indicators of truth, they are necessary to the philosophical endeavor. Specifically, he thinks that intuitions are essential sources of evidence for epistemic justification. I argue that Bealer's defense of intuitions either (1) is insufficient to show that actual human beings are in a position to use intuitions for epistemic justification, or (2) begs the question. The growing empirical data about our intuitions support the view that humans are not creatures appropriately positioned (...) to use intuitions for epistemic justification in the way Bealer suggests. Without the appropriate empirical evidence that humans are beings so positioned, his view begs the question against those who think that intuitions are not reliable guides to truth. (shrink)

This paper critically analyzes Sherrilyn Roush’s (Tracking truth: knowledge, evidence and science, 2005) definition of evidence and especially her powerful defence that in the ideal, a claim should be probable to be evidence for anything. We suggest that Roush treats not one sense of ‘evidence’ but three: relevance, leveraging and grounds for knowledge; and that different parts of her argument fare differently with respect to different senses. For relevance, we argue that probable evidence is sufficient but not necessary for Roush’s (...) own two criteria of evidence to be met. With respect to grounds for knowledge, we agree that high probability evidence is indeed ideal for the central reason Roush gives: When believing a hypothesis on the basis of e it is desirable that e be probable. But we maintain that her further argument that Bayesians need probable evidence to warrant the method they recommend for belief revision rests on a mistaken interpretation of Bayesian conditionalization. Moreover, we argue that attempts to reconcile Roush’s arguments with Bayesianism fail. For leveraging, which we agree is a matter of great importance, the requirement that evidence be probable suffices for leveraging to the probability of the hypothesis if either one of Roush’s two criteria for evidence are met. Insisting on both then seems excessive. To finish, we show how evidence, as Roush defines it, can fail to track the hypothesis. This can remedied by adding a requirement that evidence be probable, suggesting another rationale for taking probable evidence as ideal—but only for a grounds-for-knowledge sense of evidence. (shrink)

Bayesian epistemology suggests various ways of measuring the support that a piece of evidence provides a hypothesis. Such measures are defined in terms of a subjective probability assignment, pr, over propositions entertained by an agent. The most standard measure (where “H” stands for “hypothesis” and “E” stands for “evidence”) is.

Because “evidence” is at issue in evidence-based medicine (EBM), the critical responses to the movement have taken up themes from post-positivist philosophy of science to demonstrate the untenability of the objectivist account of evidence. While these post-positivist critiques seem largely correct, I propose that when they focus their analyses on what counts as evidence, the critics miss important and desirable pragmatic features of the evidence-based approach. This article redirects critical attention toward EBM’s rigid hierarchy of evidence as the culprit of (...) its objectionable epistemic practices. It reframes the EBM discourse in light of a distinction between objectivist and pragmatic epistemology, which allows for a more nuanced analysis of EBM than previously offered: one that is not either/or in its evaluation of the decision-making technology as either iconoclastic or creedal. (shrink)

Timothy Williamson’s project in Knowledge and Its Limits (Williamson, 2000)1 includes proposals for substantial revisions in the received approach to epistemology. One received view is that knowledge is conceptualized in terms of a conjunction of factors that are individually necessary and jointly sufficient for knowing. A central aim of epistemology is to state such necessary and sufficient conditions. Against this received view, Williamson argues that a necessary but insufficient condition need not be a conjunct of a non-circular necessary and sufficient (...) condition. Although being coloured is a necessary but insufficient condition for being red, we cannot state a necessary and sufficient condition for being red by conjoining being coloured with other properties specified without reference to red. Neither the equation ‘Red = coloured + X’ nor the equation ‘Knowledge = true belief + X’ need have a non-circular solution. (3) Williamson further argues that we have inductive reasons for thinking that no analysis of the concept knows of the standard kind is correct. The inductive reasons are simply the history of failed attempts at such “factorizing” or “decompositional” analyses. Williamson not only rejects the prospect of explaining knowledge in terms of belief, justification, and evidence, but he proposes to reverse the order of explanation. That order of explanation has been reversed in this book. The concept knows is fundamental, the primary implement of epistemological inquiry. (185) It is not altogether easy, however, to reconcile this radical program with other things Williamson says in the book. In particular, the book contains two rather unrelated accounts of knowing, and one of these accounts appeals to some of the same ingredients that traditional (or semi-traditional) analysts have used in the past. The first account, which appears in Chapter 1, says that knowing is the most general factive stative propositional attitude. The account is presented in terms of three conditions: (1) If Φ is an FMSO [factive mental state operator], from ‘S Φs that A’ one may infer ‘A’.. (shrink)

Bayesian epistemology addresses epistemological problems with the help of the mathematical theory of probability. It turns out that the probability calculus is especially suited to represent degrees of belief (credences) and to deal with questions of belief change, confirmation, evidence, justification, and coherence. Compared to the informal discussions in traditional epistemology, Bayesian epis- temology allows for a more precise and fine-grained analysis which takes the gradual aspects of these central epistemological notions into account. Bayesian epistemology therefore complements traditional epistemology; it (...) does not re- place it or aim at replacing it. (shrink)

The paper attempts to give an account of the introspective self-knowledge of our own experiences which is in line with representationalism about phenomenal consciousness and the transparency of experience. A two-step model is presented. First, a demonstrative thought of the form ‚I am experiencing this’ is formed which refers to what one experiences, by means of attention. Plausibly, this thought is knowledge, since safe. Second, a non-demonstrative thought of the form ‚I am experiencing a pain’ occurs. This second self-ascription is (...) justified inferentially, on the basis of the first, demonstrative thought. Thus, an account of introspective experiential self-knowledge can be developed which is richer and more adequate to the phenomena than pure reliabilism and Dretske’s displaced perception model. There is really such a thing as introspection, but no inner sense. (shrink)

theory of knowledge defended in Timothy Williamson's book Knowledge and its Limits is compared here with the theory defended in the author's articles ‘How Knowledge Works’ and ‘Knowledge and Self-Knowledge’. It is argued that there are affinities between these theories, but that the latter has considerably more explanatory power.

The concept of evidence is central to both epistemology and the philosophy of science. Of course, ‘evidence’ is hardly a philosopher's term of art: it is not only, or even primarily, philosophers who routinely speak of evidence, but also lawyers and judges, historians and scientists, investigative journalists and reporters, as well as the members of numerous other professions and ordinary folk in the course of everyday life. The concept of evidence would thus seem to be on firmer pre-theoretical ground than (...) various other concepts which enjoy similarly central standing within philosophy. (Contrast, for example, the epistemologist's quasi-technical term ‘epistemic justification’.). (shrink)

The concept of evidence is among the central concerns of epistemology broadly construed. As such, it has long engaged the intellectual energies of both philosophers of science and epistemologists of a more traditional variety. Here I briefly survey some of the more important ideas to have emerged from this tradition of reflection. I then look somewhat more closely at an issue that has recently come to the fore, largely as a result of Williamson's Knowledge and Its Limits: that of whether (...) one's evidence supervenes on one's non-factive mental states. (shrink)

The aim of this paper is to examine the kind of evidence that might be adduced in support of relativist semantics of a kind that have recently been proposed for predicates of personal taste, for epistemic modals, for knowledge attributions and for other cases. I shall concentrate on the case of taste predicates, but what I have to say is easily transposed to the other cases just mentioned. I shall begin by considering in general the question of what kind of (...) evidence can be offered in favour of some semantic theory or framework of semantic theorizing. In other words, I shall begin with the difficult question of the empirical significance of semantic theorizing. In Sect. 2, I outline a relativist semantic theory, and in Sect. 3, I review four types of evidence that might be offered in favour of a relativistic framework. I show that the evidence is not conclusive because a sophisticated form of contextualism (or indexical relativism) can stand up to the evidence. However, the evidence can be taken to support the view that either relativism or the sophisticated form of contextualism is correct. (shrink)

The evidence of your own eyes has often been regarded as unproblematic. But we know that people make mistaken observations. This can be looked on as unimportant if there issome class of statements that can serve as evidence for others, or if every statement in our corpus of knowledge is allowed to be no more than probable. Neither of these alternatives is plausible when it comes to machine or robotic observation. Then we must take the possibility of error seriously, and (...) we must be prepared to deal with error quantitatively. The problem of using internal evidence to arrive at error distributions is the main focus of the paper. (shrink)

I want to discuss a problem that arises when you try to combine an attractive account of what constitutes evidence with an independently plausible account of the kind of access we have to our evidence. According to E = K, our evidence consists of what we know. According to the principle of armchair access, if a proposition is part of our evidence we ought to be able to know that this proposition is part of our evidence ‘from the armchair’. Combined, (...) these claims entail that we can have armchair knowledge of the external world. Because it seems that the principle of armchair access is supported by a widely shared intuition about epistemic rationality, it seems we ought to embrace an internalist conception of evidence. I shall argue that this response is mistaken. Because externalism about evidence can accommodate the relevant intuitions about epistemic rationality, the principle of armchair access is unmotivated. We also have independent reasons for preferring externalism about evidence to the principle of armchair access. (shrink)

Conciliatory views of disagreement maintain that discovering a particular type of disagreement requires that one make doxastic conciliation. In this paper I give a more formal characterization of such a view. After explaining and motivating this view as the correct view regarding the epistemic significance of disagreement, I proceed to defend it from several objections concerning higher-order evidence (evidence about the character of one’s evidence) made by Thomas Kelly (2005).

This book is a collection of materials concerned not only with the law of evidence, but also with the logical and rhetorical aspects of proof; the epistemology of evidence as a basis for the proof of disputed facts; and scientific aspects of the subject. The editor also raises issues such as the philosophical basis for the use of evidence.

A systematic study of rational or justified belief, which throws fresh light on current debates about foundations and coherence theories of knowledge, the validation of induction and moral scepticism. Dr Nathan focuses attention on the largely unsatisfiable desires for active and self-conscious assurance of truth liable to be engendered by philosophical reflection about total belief-systems and the sources of knowledge. He extracts a kernel of truth from the doctrine that a regress of justification is both necessary and impossible, contrasts the (...) resultant scepticism with more familiar complaints about the inapplicability of supposedly essential cognitive concepts and explores the feasibility of non-Humean modes of consolation. This is an original and carefully constructed book, which will interest professional philosophers and advanced students of epistemology. (shrink)

The definition of memory knowledge that p put forward in this paper is nontraditional in that the justification for the belief that p which constitutes that knowledge is not located in any memory-impression or other present state of the subject. Rather it is the subject's actual past justification for p, or a proper part thereof, that justifies this present belief that p. It is argued (1) that the notion under definition is that of knowing straight from memory, (2) that an (...) adequate definition here must take into account a difference, as to conflicting evidence one does not possess, between evidence one has forgotten and evidence one has never had, (3) that compared to Ginet's traditional definition (1975), the definition has several advantages, and (4) that the definition handles at least one type of situation where there can be memory knowledge that p without previous knowledge that p. (shrink)

My topic in this paper is a particular species of epistemic justification – a species that, following Roderick Firth, I call “propositional justification.”1 Propositional justification is a relation between a person and a proposition. I will say that for S to bear the propositional justification relation to p is for S to be “justified in believing” that p. What is propositional justification? What is it for S to be justified in believing that p? Here’s my answer.

I offer a critical treatment of the contrastivist response to the problem of radical scepticism. In particular, I argue that if contrastivism is understood along externalist lines then it is unnecessary, while if it is understood along internalist lines then it is intellectually dissatisfying. Moreover, I claim that a closer examination of the conditions under which it is appropriate to claim knowledge reveals that we can accommodate many of the intuitions appealed to by contrastivists without having to opt for this (...) particular brand of epistemological revisionism. (shrink)

This book is concerned with the role of intuitions in the justification of philosophical theory. The author begins by demonstrating how contemporary philosophers, whether engaged in case-driven analysis or seeking reflective equilibrium, rely on intuitions as evidence for their theories. The author then provides an account of the nature of philosophical intuitions and distinguishes them from other psychological states. Finally, the author defends the use of intuitions as evidence by demonstrating that arguments for skepticism about their evidential value are either (...) self-defeating or guilty of arbitrary and unjustified partiality towards non-intuitive modes of knowledge. (shrink)

Timothy Williamson has argued that a person S ’s total evidence is constituted solely by propositions that S knows. This theory of evidence entails that a false belief can not be a part of S ’s evidence base for a conclusion. I argue by counterexample that this thesis (E = K for now) forces an implausible separation between what it means for a belief to be justified and rational from one’s perspective and what it means to base one’s beliefs on (...) the evidence. Furthermore, I argue that E = K entails the implausible result that there are cases in which a well-evidenced belief necessarily can not serve as evidence for a further proposition. (shrink)

A single argument template—the EPH template—can be used to generate versions of the best known and most challenging skeptical problems. In his brilliantly groundbreaking book Knowledge and Its Limits, Timothy Williamson presents a theory of knowledge and evidence which he clearly intends to provide a response to skepticism in its most important forms. After laying out EPH skepticism and reviewing possible ways of responding to it, I show how elements of Williamson’s theory motivate a hitherto unexplored way of responding to (...) EPH-generated skeptical arguments. Then I offer reasons to doubt the correctness of Williamson’s response. (shrink)

A single argument template—the EPH template—can be used to generate versions of the best known and most challenging skeptical problems. In his brilliantly groundbreaking book Knowledge and Its Limits, Timothy Williamson presents a theory of knowledge and evidence which he clearly intends to provide a response to skepticism in its most important forms. After laying out EPH skepticism and reviewing possible ways of responding to it, I show how elements of Williamson’s theory motivate a hitherto unexplored way of responding to (...) EPH-generated skeptical arguments. Then I offer reasons to doubt the correctness of Williamson’s response. (shrink)

In sec. 1.1 I emphasize the meliorative purpose of epistemology, and I characterize Goldman's epistemology as reliabilistic, cognitive, social, and meliorative. In sec. 1.2 I point out that Goldman's weak notion of knowledge is in conflict with our ordinary usage of 'knowledge'. In sec. 2 I argue for an externalist-internalist hybrid conception of justification which adds reliability-indicators to externalist knowledge. Reliability-indicators produce a veritistic surplus value for the social spread of knowledge. In sec. 3 I analyze some particular meliorative rules (...) which have been proposed by Goldman. I prove that obedience to the rule of maximally specific evidence increases expected veritistic value (sec. 3.1), and I argue that rule-circular arguments are epistemically worthless (sec. 3.2). In the final sec. 3.3 I report a non-circular justification of meta-induction which has been developed elsewhere. (shrink)