Coherentists on epistemic justification claim that all justification is inferential, and that beliefs, when justified, get their justification together (not in isolation) as members of a coherent belief system. Some recent work in formal epistemology shows that “individual credibility” is needed for “witness agreement” to increase the probability of truth and generate a high probability of truth. It can seem that, from this result in formal epistemology, it follows that coherentist justification is not truth-conducive, that it is not the case (...) that, under the requisite conditions, coherentist justification increases the probability of truth and generates a high probability of truth. I argue that this does not follow. (shrink)

This paper looks at the question of what form the requirements of practical rationality take. One common view is that the requirements of rationality are wide-scope, and another is that they are narrow-scope. I argue that the resolution to the question of wide-scope versus narrow-scope depends to a significant degree on what one expects a theory of rationality to do. In examining these expectations, I consider whether there might be a way to unify requirements of both forms into a single (...) theory of rationality, and what the difficulties involved in doing so can teach us about the foundations of practical rationality. (shrink)

__In this paper I investigate unification as a virtue of explanation. I the first part of the paper I give a brief exposition of the unification account of Schurz and Lambert and Schurz. I illustrate the advantages of this account in comparison to the older unification accounts of Friedman and Kitcher. In the second part I discuss several comments and objections to the Schurz-Lambert account that were raised by Weber and van Dyck, Gijsberg and de Regt. In the third and (...) final part, I argue that explanation should be understood as a prototype concept which contains nomic expectability, causality and unification as prototypical virtues of explanations, although none of these virtues provides a sufficient and necessary "defining condition" of explanation. (shrink)

I develop a probabilistic account of coherence, and argue that at least in certain respects it is preferable to (at least some of) the main extant probabilistic accounts of coherence: (i) Igor Douven and Wouter Meijs’s account, (ii) Branden Fitelson’s account, (iii) Erik Olsson’s account, and (iv) Tomoji Shogenji’s account. Further, I relate the account to an important, but little discussed, problem for standard varieties of coherentism, viz., the “Problem of Justified Inconsistent Beliefs.”.

Some recent work in formal epistemology shows that “witness agreement” by itself implies neither an increase in the probability of truth nor a high probability of truth—the witnesses need to have some “individual credibility.” It can seem that, from this formal epistemological result, it follows that coherentist justification (i.e., doxastic coherence) is not truth-conducive. I argue that this does not follow. Central to my argument is the thesis that, though coherentists deny that there can be noninferential justification, coherentists do not (...) deny that there can be individual credibility. (shrink)

In the first part of this paper, we argue that the claim that a subject S believes that ϕ on the basis of good reasons cannot be the only type of explanation why S rationally believes that ϕ. Explaining attributions of rationality only by means of the notion of a belief being based on good reasons generates one version of the problem of regress of reasons. In the second part we flesh out a hypothesis according to which some beliefs are (...) rationally held by a subject S in virtue of the fact that S knows how to produce good reasons for holding them. In the third part we offer reasons for accepting the relevant hypothesis, and we argue that it is more successful than foundationalist, coherentist and infinitist theories in explaining the truth of some attributions of epistemic rationality. In the last part we address the problem of the regress of reasons and sketch a solution for it based on our hypothesis. (shrink)

The variety-of-evidence thesis has been criticized by Bovens and Hartmann. This article points to two limitations of their Bayesian model: the conceptualization of unreliable evidential sources as randomizing and the restriction to comparing full independence to full dependence. It is shown that the variety-of-evidence thesis is rehabilitated when unreliable sources are reconceptualized as systematically biased. However, it turns out that allowing for degrees of independence leads to a qualification of the variety-of-evidence thesis: as Bovens and Hartmann claimed, more independence does (...) not always imply stronger confirmation. (shrink)

It is sometimes assumed in the Bayesian coherentist literature that the project of finding a truth-conducive measure of coherence of testimonial contents will, if successful, be helpful to the coherentist theory of justification. Various impossibility results in the Bayesian coherentist literature are consequently taken to be prima facie detrimental to the coherentist theory of justification. These attempts to connect Bayesian coherentism to the coherentist/ foundationalist debate in classical epistemology rest upon a confusion between the justification of a proposition and the (...) credibility that a proposition has for some other proposition. Foundationalism requires a class of beliefs that have non- inferential justification, not beliefs that have credibility by themselves for others. Coherentists insist that beliefs can be justified only via inferential relations with others, but this does not mean that coherentists must deny that individual propositions can have credibility for other propositions. I analyze and respond to both Erik Olsson's and Michael Huemer's arguments concerning the alleged connection between the Bayesian coherentist project and the coherentist theory of justification. Finally, I argue that Bayesian coherentism as represented in the literature, so far from being a version of coherentism, is implicitly foundationalist because of its treatment of “witness reports”, especially the reports of memory and sensation, as given evidence. The impossibility results, based on the assumption of given reports, are therefore not targeted at classical coherentism in epistemology at all. (shrink)

This paper examines the role of coherence of evidence in what I call the non-dynamic model of confirmation. It appears that other things being equal, a higher degree of coherence among pieces of evidence raises to a higher degree the probability of the proposition they support. I argue against this view on the basis of three related observations. First, we should be able to assess the impact of coherence on any hypothesis of interest the evidence supports. Second, the impact of (...) coherence among the pieces of evidence can be different on different hypotheses of interest they support. Third, when we assess the impact of coherence on a hypothesis of interest, other conditions that should be held equal for a fair assessment include the degrees of individual support which the propositions directly supported by the respective pieces of evidence provide for the hypothesis. Once we take these points into consideration, the impression that coherence of evidence plays a positive role in confirmation dissipates. In some cases it can be shown that other things being equal, a higher degree of coherence among the pieces of evidence reduces the degree of confirmation for the hypothesis they support. (shrink)

Economists reason causally. Like many other scientists, they aim at formulating justified causal claims about their object of study. This thesis contributes to our understanding of how causal reasoning proceeds in economics. By using the research on the causes of unemployment as a case study, three questions are adressed. What are the meanings of causal claims? How can a causal claim be adequately supported by evidence? How are causal beliefs affected by incoming facts? In the process of answering these semantic, (...) epistemic and dynamical questions, the richness of causal reasoning in economics is brought to the foreground. In the part on semantics, it is argued that the meaning of causal generalizations in policy-oriented economics is best captured by using the concept of ‘inferential relation’ rather than the one of ‘referential relation’. This part contributes to develop an inferentialist semantics by distinguishing among types of inferential relations. In the part on epistemology, it is argued that justification in sciences like economics often relies, and ought to rely, on evidential variety―i.e. the combination of evidence from multiple sources. An interpretation of independence among evidential sources is offered: two evidential sources are fully independent if and only if the reasons why they would be unreliable do not overlap. It is then shown that the variety-of-evidence thesis does not hold under extreme circumstances. The part on dynamics focuses on deviant-case study. A storyline is provided for what deviant-case study aims at and how it proceeds in what is characterized as an ‘eclectic science’. (shrink)

Special issue. With contributions by Luc Bovens and Stephan Hartmann, David Glass, Keith Lehrer, Erik Olsson, Tomoji Shogenji, Mark Siebel, and Paul Thagard.

Recent results in the literature appear to show that it is impossible for two independent testimonies to jointly raise the probability of a proposition if neither testimony individually has any impact on that probability. I show that these impossibility results do not apply when testimonies agree on incidental details.