The notion of epistemic coherence is interpreted as involving not only consistency but also stability. The problem how to consolidate a belief system, i.e., revise it so that it becomes coherent, is studied axiomatically as well as in terms of set-theoretical constructions. Representation theorems are given for subtractive consolidation (where coherence is obtained by deleting beliefs) and additive consolidation (where coherence is obtained by adding beliefs).
According to the Argument from Disagreement (AD) widespread and persistent disagreement on ethical issues indicates that our moral opinions are not influenced by moral facts, either because there are no such facts or because there are such facts but they fail to influence our moral opinions. In an innovative paper, Gustafsson and Peterson (Synthese, published online 16 October, 2010) study the argument by means of computer simulation of opinion dynamics, relying on the well-known model of Hegselmann and Krause (J Artif (...) Soc Soc Simul 5(3):1–33, 2002; J Artif Soc Soc Simul 9(3):1–28, 2006). Their simulations indicate that if our moral opinions were influenced at least slightly by moral facts, we would quickly have reached consensus, even if our moral opinions were also affected by additional factors such as false authorities, external political shifts and random processes. Gustafsson and Peterson conclude that since no such consensus has been reached in real life, the simulation gives us increased reason to take seriously the AD. Our main claim in this paper is that these results are not as robust as Gustafsson and Peterson seem to think they are. If we run similar simulations in the alternative Laputa simulation environment developed by Angere and Olsson (Angere, Synthese, forthcoming and Olsson, Episteme 8(2):127–143, 2011) considerably less support for the AD is forthcoming. (shrink)
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)
Knowledge is more valuable than mere true belief. Many authors contend, however, that reliabilism is incompatible with this item of common sense. If a belief is true, adding that it was reliably produced doesn't seem to make it more valuable. The value of reliability is swamped by the value of truth. In Goldman and Olsson (2009), two independent solutions to the problem were suggested. According to the conditional probability solution, reliabilist knowledge is more valuable in virtue of being a (...) stronger indicator than mere true belief of future true belief. This article defends this solution against some objections. (shrink)
A measure of coherence is said to be truth conducive if and only if a higher degree of coherence (as measured) results in a higher likelihood of truth. Recent impossibility results strongly indicate that there are no (non-trivial) probabilistic coherence measures that are truth conducive. Indeed, this holds even if truth conduciveness is understood in a weak ceteris paribus sense (Bovens & Hartmann, 2003, Bayesian epistemology. New York, Oxford: Oxford University Press; Olsson, 2005, Against coherence: Truth probability and justification. (...) Oxford: Oxford University Press). This raises the problem of how coherence could nonetheless be an epistemically important property. Our proposal is that coherence may be linked in a certain way to reliability. We define a measure of coherence to be reliability conducive if and only if a higher degree of coherence (as measured) results in a higher probability that the information sources are reliable. Restricting ourselves to the most basic case, we investigate which coherence measures in the literature are reliability conducive. It turns out that, while a number of measures fail to be reliability conducive, except possibly in a trivial and uninteresting sense, Shogenji’s measure and several measures generated by Douven and Meijs’s recipe are notable exceptions to this rule. (shrink)
We reply to Christoph Jäger's criticism of the conditional probability solution (CPS) to the value problem for reliabilism due to Goldman and Olsson (2009). We argue that while Jäger raises some legitimate concerns about the compatibility of CPS with externalist epistemology, his objections do not in the end reduce the plausibility of that solution.
In an earlier paper, I objected to certain elements of L. Jonathan Cohen's account of corroborating testimony (Olsson [2002]). In their response to my article, Bovens, Fitelson, Hartmann and Snyder ([2002]) suggest some significant improvements of the probabilistic model which I used in assessing Cohen's theses and answer some additional questions which my study raised. More problematically, they also seek to defend Cohen against my criticism. I argue, in this reply, that their attempts in this direction are unsuccessful.
It is a widely accepted doctrine in epistemology that knowledge has greater value than mere true belief. But although epistemologists regularly pay homage to this doctrine, evidence for it is shaky. Is it based on evidence that ordinary people on the street make evaluative comparisons of knowledge and true belief, and consistently rate the former ahead of the latter? Do they reveal such a preference by some sort of persistent choice behavior? Neither of these scenarios is observed. Rather, epistemologists come (...) to this conclusion because they have some sort of conception or theory of what knowledge is, and they find reasons why people should rate knowledge, so understood, ahead of mere true belief. But what if these epistemological theories are wrong? Then the assumption that knowledge is more valuable than true belief might be in trouble. We don’t wish to take a firm position against the thesis that knowledge is more valuable than true belief. But we begin this paper by arguing that there is one sense of ‘know’ under which the thesis cannot be right. In particular, there seems to be a sense of ‘know’ in which it means, simply, ‘believe truly.’ If this is correct, then knowledge—in this weak sense of the term—cannot be more valuable than true belief. What evidence is there for a weak sense of ‘knowledge’ in which it is equivalent to ‘true belief’? Knowledge seems to contrast with ignorance. Not only do knowledge and ignorance contrast with one another but they seem to exhaust the alternatives, at least for a specified person and fact. Given a true proposition p, Diane either knows p or is ignorant of it. The same point can be expressed using rough synonyms of ‘know.’ Diane is either aware of (the fact that) p or is ignorant of it. She is either cognizant of p or ignorant of it. She either possesses the information that p or she is uninformed (ignorant) of it. To illustrate these suggestions, consider a case discussed by John Hawthorne (2002). If I ask you how many people in the room know that Vienna is the capital of Austria, you will tally up the number of people in the room who possess the information that Vienna is the capital of Austria.. (shrink)
According to the so?called swamping problem, reliabilist knowledge is no more valuable than mere true belief. In a paper called ?Reliabilism and the value of knowledge? (in Epistemic value, edited by A. Haddock, A. Millar, and D. H. Pritchard, pp. 19?41. Oxford: Oxford University Press, 2009), Alvin I. Goldman and myself proposed, among other things, a solution based on conditional probabilities. This approach, however, is heavily criticized by Jonathan L. Kvanvig in his paper ?The swamping problem redux: Pith and gist? (...) (in Social Epistemology, edited by A. Haddock, A. Millar, and D. H. Pritchard, pp. 89?111. Oxford: Oxford University Press, 2010). In the present article, I defend the conditional probability solution against Kvanvig?s objections. (shrink)
Let us by ‘first-order beliefs’ mean beliefs about the world, such as the belief that it will rain tomorrow, and by ‘second-order beliefs’ let us mean beliefs about the reliability of first-order, belief-forming processes. In formal epistemology, coherence has been studied, with much ingenuity and precision, for sets of first-order beliefs. However, to the best of our knowledge, sets including second-order beliefs have not yet received serious attention in that literature. In informal epistemology, by contrast, sets of the latter kind (...) play an important role in some respectable coherence theories of knowledge and justification. In this paper, we extend the formal treatment of coherence to second-order beliefs. Our main conclusion is that while extending the framework to second-order beliefs sheds doubt on the generality of the notorious impossibility results for coherentism, another problem crops up that might be no less damaging to the coherentist project: facts of coherence turn out to be epistemically accessible only to agents who have a good deal of insight into matters external to their own belief states. (shrink)
Keith Lehrer is one of the leading proponents of a coherence theory of knowledge that seeks to explain what it means to know in a characteristically human way. Central to his account are the pivotal role played by a principle of self-trust and his insistence that a sound epistemology must ultimately be ecumenical in nature, combining elements of internalism and externalism. The present book is an extensive, self-contained, up-to-date study of Lehrer's epistemological work. Covering all major aspects, it contains original (...) contributions by some of the most distinguished specialists in the field, outgoing from the latest, significantly revised version of Lehrer's theory. All basic ideas are explained in an introductory chapter. Lehrer's extensive replies in a final chapter give unique access to his current epistemological thinking. (shrink)
We prove that four theses commonly associated with coherentism are incompatible with the representation of a belief state as a logically closed set of sentences. The result is applied to the conventional coherence interpretation of the AGM theory of belief revision, which appears not to be tenable. Our argument also counts against the coherentistic acceptability of a certain form of propositional holism. We argue that the problems arise as an effect of ignoring the distinction between derived and non-derived beliefs, and (...) we suggest that the kind of coherence relevant to epistemic justification is the coherence of non-derived beliefs. (shrink)
Jonathan Cohen has claimed that in cases of witness agreement there is an inverse relationship between the prior probability and the posterior probability of what is being agreed: the posterior rises as the prior falls. As is demonstrated in this paper, this contention is not generally valid. In fact, in the most straightforward case exactly the opposite is true: a lower prior also means a lower posterior. This notwithstanding, there is a grain of truth to what Cohen is saying, as (...) there are special circumstances under which a thesis similar to his holds good. What characterises these circumstances is that they allow for the fact of agreement to be surprising. In making this precise, I draw on Paul Horwich's probabilistic analysis of surprise. I also consider a related claim made by Cohen concerning the effect of lowering the prior on the strength of corroboration. 1 Introduction 2 Cohen's claim 3 A counterexample 4 A weaker claim 5 A counterexample to the weaker claim 6 The grain of truth in Cohen's claim 7 Prior probability and strength of corroboration 8 Conclusion. (shrink)
Pragmatist responses to radical skepticism do not receive much attention in contemporary analytic epistemology. This observation is my motivation for undertaking a search for a coherent pragmatist reply to radical doubt, one that can compete, in terms of clarity and sophistication, with the currently most popular approaches, such as contextualism and relevant alternatives theory. As my point of departure I take the texts of C. S. Peirce and William James. The Jamesian response is seen to consist in the application of (...) a wager argument to the skeptical issue in analogy with Pascal's wager. The Peircean strategy, on the other hand, is to attempt a direct rejection of one of the skeptic's main premises: that we do not know we are not deceived. I argue that while the Jamesian attempt is ultimately incoherent, Peirce's argument contains the core of a detailed and characteristically "pragmatic" rebuttal of skepticism, one that deserves to be taken seriously in the contemporary debate. (shrink)
There is an emerging consensus in the literature on probabilistic coherence that such coherence cannot be truth conducive unless the information sources providing the cohering information are individually credible and collectively independent. Furthermore, coherence can at best be truth conducive in a ceteris paribus sense. Bovens and Hartmann have argued that there cannot be any measure of coherence that is truth conducive even in this very weak sense. In this paper, I give an alternative impossibility proof. I provide a relatively (...) detailed comparison of the two results, which turn out to be logically unrelated, and argue that my result answers a question raised by Bovens and Hartmann’s study. Finally, I discuss the epistemological ramifications of these findings and try to make plausible that a shift to an explanatory framework such as Thagard’s is unlikely to turn the impossibility into a possibility. (shrink)
Isaac Levi, currently John Dewey Professor of Philosophy at Columbia University, has explored the principles of American pragmatism in greater depth and more consistency than others before him. The result is a sophisticated and powerful philosophical system whose key elements stand in stark opposition not only to current mainstream epistemology, but also to the positions of other contemporary authors writing in the same pragmatist tradition. The essays in this timely volume, written by some of philosophy's finest scholars, contribute substantially (...) to the understanding and appraisal of Levi's work. (shrink)
Hans Rott has argued, most recently in his book Change, Choice and Inference, that certain formal correspondences between belief revision and rational choice have important philosophical implications, claiming that the former strongly indicate the unity of practical and theoretical reason as well as the primacy of practical reason. In this paper, I confront Rott's argument with three serious challenges. My conclusion is that, while Rott's work is indisputable as a formal achievement, the philosophical consequences he wants to draw are not (...) forthcoming. (shrink)
I argue that the analysis most capable of systematising our intuitions about coherence as a relation is one according to which a set of beliefs, A, coheres with another set, B, if and only if the set-theoretical union of A and B is a coherent set. The second problem I consider is the role of coherence in epistemic justification. I submit that there are severe problems pertaining to the idea, defended most prominently by Keith Lehrer, that justification amounts to coherence (...) with an acceptance system. Instead I advance a more dynamic approach according to which the problem of justification is the problem of how to merge new information with old coherently, a process which is seen to be closely connected with relational coherence. (shrink)
Several philosophers have argued that our cosmos is either purposely created by some rational being(s), or else just one among a vast number of actually existing cosmoi. According to John Leslie and Peter van Inwagen, the existence of a cosmos containing rational beings is analogous to drawing the winning straw among millions of straws. The best explanation in the latter case, they maintain, is that the drawing was either rigged by someone, or else many such lotteries have taken place. Arnold (...) Zuboff claims that each person is justified in concluding that her existence did not depend on a particular sperm cell first reaching the egg. If it did so depend, her existence would be extremely improbable, and an incredible coincidence for her. Similarly, intelligent life would be an incredible coincidence for us, if this were the only actual cosmos. We reject both these purported analogies. Referring to the nonheredity of 'surprise value', we conclude that an evolutionary explanation of the presence of rational beings is sufficient; there is no further need to explain the basic features of our cosmos which make intelligent life possible. This point concerning surprise value also reveals a fundamental disanalogy between straw-drawing and cosmos creation. (shrink)
Isaac Levi has claimed that our reliance on the testimony of others, and on the testimony of the senses, commonly produces inconsistency in our set of full beliefs. This happens if what is reported is inconsistent with what we believe to be the case. Drawing on a conception of the role of beliefs in inquiry going back to Dewey, Levi has maintained that the inconsistent belief corpus is a state of ``epistemic hell'': it is useless as a basis for inquiry (...) and deliberation. As he has also noticed, the compatibility of these two elements of his pragmatist epistemology could be called into question. For if inconsistency means hell, how can it ever be rational to enter that state, and on what basis could we attempt to regain consistency? Levi, nonetheless, has tried to show that the conflict is only apparent and that no changes of his theory are necessary. In the main part of the paper I argue, by contrast, that his attempts to reconcile these components of his view are unsuccessful.The conflict is real andthus presents a genuine threat to Deweyan pragmatism, as understood by Levi. After an attempt to pinpoint exactly where the source of the problem lies, I explore some possibilities for how to come to grips with it. I conclude that Levi can keep his fundamental thesis concerning the role of beliefs in inquiry and deliberation, provided that he (i) gives up the view that the agent can legitimately escape from inconsistency, and (ii) modifies his account of prediction alias deliberate expansion by acknowledging a third desideratum, besides probability and informational value, namely, not to cause permanent breakdown further down the line of inquiry. The result is a position which is more similar to Peter Gärdenfors's than is Levi's original theory, while retaining the basic insights of the latter. (shrink)
The standard way of representing an epistemic state in formal philosophy is in terms of a set of sentences, corresponding to the agent’s beliefs, and an ordering of those sentences, reflecting how well entrenched they are in the agent’s epistemic state. We argue that this wide-spread representational view – a view that we identify as a “Quinean dogma” – is incapable of making certain crucial distinctions. We propose, as a remedy, that any adequate representation of epistemic states must also include (...) the agent’s research agenda, i.e., the list of question that are open or closed at any given point in time. If the argument of the paper is sound, a person’s questions and practical interests, on the one hand, and her beliefs and theoretical values, on the other, are more tightly interwoven than has previously been assumed to be the case in formal epistemology. (shrink)
A group is in a state of pluralistic ignorance (PI) if, roughly speaking, every member of the group thinks that his or her belief or desire is different from the beliefs or desires of the other members of the group. PI has been invoked to explain many otherwise puzzling phenomena in social psychology. The main purpose of this article is to shed light on the nature of PI states – their structure, internal consistency and opacity – using the formal apparatus (...) of Dynamic Doxastic Logic, and also to study the sense in which such states are “fragile”, i.e. to identify plausible conditions under which a PI state cascades into a state of shared belief as the result of announcement. (shrink)
Aggregating snippets from the semantic memories of many individuals may not yield a good map of an individual’s semantic memory. The authors analyze the structure of semantic networks that they sampled from individuals through a new snowball sampling paradigm during approximately 6 weeks of 1-hr daily sessions. The semantic networks of individuals have a small-world structure with short distances between words and high clustering. The distribution of links follows a power law truncated by an exponential cutoff, meaning that most words (...) are poorly connected and a minority of words has a high, although bounded, number of connections. Existing aggregate networks mirror the individual link distributions, and so they are not scale-free, as has been previously assumed; still, there are properties of individual structure that the aggregate networks do not reflect. A simulation of the new sampling process suggests that it can uncover the true structure of an individual’s semantic memory. (shrink)
Corroborating Testimony, Probability and Surprise’, Erik J. Olsson ascribes to L. Jonathan Cohen the claims that if two witnesses provide us with the same information, then the less probable the information is, the more confident we may be that the information is true (C), and the stronger the information is corroborated (C*). We question whether Cohen intends anything like claims (C) and (C*). Furthermore, he discusses the concurrence of witness reports within a context of independent witnesses, whereas the witnesses (...) in Olsson's model are not independent in the standard sense. We argue that there is much more than, in Olsson's words, ‘a grain of truth’ to claim (C), both on his own characterization as well as on Cohen's characterization of the witnesses. We present an analysis for independent witnesses in the contexts of decision-making under risk and decision-making under uncertainty and generalize the model for n witnesses. As to claim (C*), Olsson's argument is contingent on the choice of a particular measure of corroboration and is not robust in the face of alternative measures. Finally, we delimit the set of cases to which Olsson's model is applicable. 1 Claim (C) examined for Olsson's characterization of the relationship between the witnesses 2 Claim (C) examined for two or more independent witnesses 3 Robustness and multiple measures of corroboration 4 Discussion. (shrink)
In 'Corroborating Testimony, Probability and Surprise', Erik J. Olsson ascribes to L. Jonathan Cohen the claims that if two witnesses provide us with the same information, then the less probable the information is, the more confident we may be that the information is true (C), and the stronger the information is corroborated (C*). We question whether Cohen intends anything like claims (C) and (C*). Furthermore, he discusses the concurrence of witness reports within a context of independent witnesses, whereas the (...) witnesses in Olsson's model are not independent in the standard sense. We argue that there is much more than, in Olsson's words, 'a grain of truth' to claim (C), both on his own characterization as well as on Cohen's characterization of the witnesses. We present an analysis for independent witnesses in the contexts of decision-making under risk and decision-making under uncertainty and generalize the model for n witnesses. As to claim (C*), Olsson's argument is contingent on the choice of a particular measure of corroboration and is not robust in the face of alternative measures. Finally, we delimit the set of cases to which Olsson's model is applicable. (shrink)
In ‘Corroborating Testimony, Probability and Surprise’, Erik J. Olsson ascribes to L. Jonathan Cohen the claims that if two witnesses provide us with the same information, then the less probable the information is, the more confident we may be that the information is true (C), and the stronger the information is corroborated (C*). We question whether Cohen intends anything like claims (C) and (C*). Furthermore, he discusses the concurrence of witness reports within a context of independent witnesses, whereas the (...) witnesses in Olsson’s model are not independent in the standard sense. We argue that there is much more than, in Olsson’s words, ‘a grain of truth’ to claim (C), both on his own characterization as well as on Cohen’s characterization of the witnesses. We present an analysis for independent witnesses in the contexts of decision-making under risk and decision-making under uncertainty and generalize the model for n witnesses. As to claim (C*), Olsson’s argument is contingent on the choice of a particular measure of corroboration and is not robust in the face of alternative measures. Finally, we delimit the set of cases to which Olsson’s model is applicable. (shrink)
Contributing Authors: Lilli Alanen & Frans Svensson, David Alm, Gustaf Arrhenius, Gunnar Björnsson, Luc Bovens, Richard Bradley, Geoffrey Brennan & Nicholas Southwood, John Broome, Linus Broström & Mats Johansson, Johan Brännmark, Krister Bykvist, John Cantwell, Erik Carlson, David Copp, Roger Crisp, Sven Danielsson, Dan Egonsson, Fred Feldman, Roger Fjellström, Marc Fleurbaey, Margaret Gilbert, Olav Gjelsvik, Kathrin Glüer & Peter Pagin, Ebba Gullberg & Sten Lindström, Peter Gärdenfors, Sven Ove Hansson, Jana Holsanova, Nils Holtug, Victoria Höög, Magnus Jiborn, Karsten Klint Jensen, (...) Sigurður Kristinsson, Isaac Levi, Kasper Lippert-Rasmussen, David Makinson, Anna-Sofia Maurin, Philippe Mongin, Kevin Mulligan, Lennart Nordenfelt, Jonas Olson, Erik J. Olsson, Ingmar Persson, Johannes Persson, Björn Petersson, Philip Pettit, Hans Rott, Toni Rønnow-Rasmussen, Krister Segerberg, John Skorupski, Howard Sobel, Fredrik Stjernberg, Fred Stoutland, Caj Strandberg, Pär Sundström, Folke Tersman, Torbjörn Tännsjö, Peter Vallentyne, Bruno Verbeek, Stella Villarmea, and Michael J. Zimmerman. (shrink)
Olsson and his collaborators have proposed an extension of Belief Revision Theory where an epistemic state is modeled as a triple S=⟨K_,E,A_⟩ , where A_ is a research agenda, i.e. a set of research questions. Contraction and expansion apply to states, and affect the agenda. We propose an alternative characterization of the problem of agenda updating, where research questions are viewed as blueprints for research strategies. We offer a unified solution to this problem, and prove it equivalent to (...) class='Hi'>Olsson’s own. We conclude arguing that: (i) our solution makes the idea of ‘minimal change’ in questions and agendas clearer; (ii) can be extended in ways the original theory was not, and may help better realize the aims this theory was proposed for; (iii) unveils some limitations of the initial approach, yet opening a way to overcome them. (shrink)
