Reliability conducive measures of coherence

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.     

Truth, Warrant and Superassertibility

In a recent paper on Truth, Knowability and Neutrality Timothy Kenyon sets out to defend the coherence of a putative anti-realist truth-predicate, superassertibility, due to Wright (1992, 1999), against a number of Wright’s critics. By his own admission, the success of Kenyon’s defensive strategies turns out to hinge upon a realist conception of absolute warrant which conflicts with the anti-realist character of the original proposal, based, as it was, on a notion of defeasible warrant. Kenyon’s potential success in resisting Wright’s critics brings a pyrrhic victory: either way, realism wins. Here I argue that the link between superassertibility and defeasible warrant can be restored in a way which clarifies the consistency of the pair, provided that the notion of inference to superassertibility is properly understood in logical terms. As one might expect, the requisite notion is not classical in character. As one might not expect, the notion cannot be properly construed in intuitionist terms either. Hence, I propose an alternative logical framework which, I believe, is at least formally adequate to the representation of superassertibility on the basis of defeasible warrant. The price to be paid for rejecting the ‘third way’ proposed here in favour of either of the two more traditional logical options is precisely that indicated by Kenyon’s discussion.     

Against the possibility of historical evidence for miracles

In his bookThe Concept of Miracle and his paper ‘For the Possibility of Miracles’ Swinburne claims that there are no logical difficulties in supposing that there could be strong historical evidence for the occurrence of miracles. This claim is based on three assertions; two of which I demonstrate are only true contingently. In this paper I identify several logical difficulties regarding the possibility of attaining historical evidence for the occurrence of miracles. On the strength of these logical difficulties I hope to demonstrate that there is sufficient reason to doubt Swinburne’s central claim.     

The Impossibility of Coherence

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.     

Knowledge, Naturalism, and Cognitive Ethology: Kornblith’s Knowledge and its Place in Nature

This paper explores Kornblith’s proposal in Knowledge and its Place in Nature that knowledge is a natural kind that can be elucidated and understood in scientific terms. Central to Kornblith’s development of this proposal is the claim that there is a single category of unreflective knowledge that is studied by cognitive ethologists and is the proper province of epistemology. This claim is challenged on the grounds that even unreflective knowledge in language-using humans reflects forms of logical reasoning that are in principle unavailable to nonlinguistic animals.     

Thomason’s Paradox for Belief,and Two Consequence Relations

Thomason (1979/2010)’s argument against competence psychologism in semantics envisages a representation of a subject’s competence as follows: he understands his own language in the sense that he can identify the semantic content of each of its sentences, which requires that the relation between expression and content be recursive. Then if the scientist constructs a theory that is meant to represent the body of the subject’s beliefs, construed as assent to the content of the pertinent sentences, and that theory satisfies certain ‘natural assumptions’, then it implies that the subject is inconsistent if the beliefs include arithmetic. I challenge the result by insisting that the motivation for Thomason’s principle (ii), via Moore’s Paradox, leads to a more complex representation, in which stating the facts and expressing one’s beliefs are treated differently. Certain logical connections among expressions of assent, and between expression and statement, are a matter of consequence on pain of pragmatic incoherence, not consequence on pain of classical logical inconsistency. But while this salvages the possibility that a modification of the above sort of representation could be adequate, Thomason’s devastating conclusion returns if the scientist identifies himself as the subject of that representation, even when paying heed to the requirement of pragmatic coherence of the sort highlighted by Moore’s Paradox.     

Should Moore have Followed his Own Method?

I discuss Soames’s proposal that Moore could have avoided a central problem in his moral philosophy if he had utilized a method he himself pioneered in epistemology. The problem in Moore’s moral philosophy concerns what it is for a moral claim to be self-evident. The method in Moore’s epistemology concerns not denying the obvious. In review of the distance between something’s being self-evident and its being obvious, it is suggested that Soames’s proposal is mistaken.     

Internalism and Hyperexternalism About Reasons

Alan Goldman’s Reasons from Within is one of the most thorough recent defenses of what might be called ‘orthodox internalism’ about practical reasons. Goldman’s main target is an opposing view that includes a commitment to the following two theses: (O) that there are such things as objective values, and (E) that these values give rise to external reasons. One version of this view, which we can call ‘orthodox externalism’, also includes a commitment to the thesis (I) that rational people will be motivated by any reason they have of which they are aware. Goldman himself embraces (I), and deploys it frequently in his criticisms of orthodox externalism. But there is logical space for an externalist view that includes a commitment to (O) and (E), but that denies (I). The resulting “hyperexternalist” view holds that some reasons need not motivate us, even if we are rational. In this paper I argue that Goldman’s criticisms of orthodox externalism leave hyperexternalism untouched, and that his specific criticisms of my own version of hyperexternalism do not work. In light of Goldman’s criticisms of orthodox externalism and my own criticisms of Goldman’s view, hyperexternalism emerges as the favored option.     

Liberalism,Abstract Individualism,and the Problem of Particular Obligations

In the following I take issue with the allegation that liberalism must inevitably be guilty of ‘abstract individualism’. I treat Michael Sandel’s well-known claim that there are ‘loyalties and convictions whose moral force consists partly in the fact that living by them is inseparable from understanding ourselves as the particular persons we are’ as representative of this widely held view. Specifically, I argue: (i) that Sandel’s account of the manner in which ‘constitutive’ loyalties function as reasons for action presupposes the possibility of there being (what I call) ‘underivable particular obligations’, but that such obligations are, in fact, a logical impossibility; and (ii) that Sandel’s account of the self as necessarily ‘encumbered’ presupposes an account of personal identity which confuses identification with definition, and which is, therefore, fundamentally flawed. For their constructive and insightful comments on an earlier draft of this paper, I owe a special debt of gratitude to the following: Clare Chambers, Roger Crisp, Cécile Fabre, Paul Kelly, David Lloyd-Thomas. Thanks also go to Res Publica’s two anonymous referees.     

The fate of the direct argument and the case for incompatibilism

In this paper, I distinguish causal from logical versions of the direct argument for incompatibilism. I argue that, contrary to appearances, causal versions are better equipped to withstand an important recent challenge to the direct-argument strategy. The challenge involves arguing that support for the argument’s pivotal inference principle falls short just when it is needed most, namely when a deterministic series runs through an agent’s unimpaired deliberations. I then argue that, while there are limits to what causal versions can accomplish, they can be used to buttress the ultimacy argument, another important argument for incompatibilism.     

Roger Swyneshed’s Obligationes: A Logical Game of Inference Recognition?

In [Dutilh Novaes, Medieval-obligations as logical Games of Consistency maintenance, synthese, (2004)], I proposed a reconstruction of Walter Burley’s theory of obligationes, based on the idea that Burley’s theory of obligationes could be seen as a logical game of consistency maintenance. In the present paper, I intend to test the game hypothesis on another important theory of obligationes, namely Roger Swyneshed’s theory. In his treatise on obligationes [edited by P.V. Spade, cf. Spade History and philosophy of Logic 3(1982) 1-32], Swyneshed introduced significant modifications to the general framework of obligationes. To compare the two theories, I apply the same formal apparatus used in the previous paper. It will become patent that Swyneshed’s theory is considerably different from Burley’s, among other reasons because the dynamic aspects that play a major role in the latter are simply not present in the former. My conclusion is that Swyneshed’s version of obligationes is not directed towards consistency maintenance, but rather towards inference recognition, and that it is, from a game-theoretical perspective, less interesting a theory than Burley’s.     

Non-monotonicity and Informal Reasoning: Comment on Ferguson (2003)

In this paper, it is argued that Ferguson’s (2003, Argumentation 17, 335–346) recent proposal to reconcile monotonic logic with defeasibility has three counterintuitive consequences. First, the conclusions that can be derived from his new rule of inference are vacuous, a point that as already made against default logics when there are conflicting defaults. Second, his proposal requires a procedural “hack” to the break the symmetry between the disjuncts of the tautological conclusions to which his proposal leads. Third, Ferguson’s proposal amounts to arguing that all everyday inferences are sound by definition. It is concluded that the informal logic response to defeasibility, that an account of the context in which inferences are sound or unsound is required, still stands. It is also observed that another possible response is given by Bayesian probability theory (Oaksford and Chater, in press, Bayesian Rationality: The Probabilistic Approach to Human Reasoning, Oxford University Press, Oxford, UK; Hahn and Oaksford, in press, Synthese).     

Actuality, Necessity, and Logical Truth

The traditional view that all logical truths are metaphysically necessary has come under attack in recent years. The contrary claim is prominent in David Kaplan’s work on demonstratives, and Edward Zalta has argued that logical truths that are not necessary appear in modal languages supplemented only with some device for making reference to the actual world (and thus independently of whether demonstratives like ‘I’, ‘here’, and ‘now’ are present). If this latter claim can be sustained, it strikes close to the heart of the traditional view. I begin this paper by discussing and refuting Zalta’s argument in the context of a language for propositional modal logic with an actuality connective (section 1). This involves showing that his argument in favor of real world validity his preferred explication of logical truth, is fallacious. Next (section 2) I argue for an alternative explication of logical truth called general validity. Since the rule of necessitation preserves general validity, the argument of section 2 provides a reason for affirming the traditional view. Finally (section 3) I show that the intuitive idea behind the discredited notion of real world validity finds legitimate expression in an object language connective for deep necessity. Earlier versions of this paper were read at the universities of Graz, Maribor, and Salzburg, and at a workshop on the philosophy of logic at the National Autonomous University of Mexico (UNAM) in Mexico City. My thanks to those present at these events for many helpful suggestions. Thanks are also due to an anonymous referee for Philosophical Studies.     

How is God-talk logically possible? A sketch for an argument on the logic of ‘God’

In this paper I want to argue for the optimal way to characterise the logical and semantical behaviour of the singular term ‘God’ used in religious language. The relevance of this enterprise to logical theory is the main focus as well. Doing this presupposes to outline the two rivaling approaches of well-definition of singular terms: Kripke’s (“rigid designators”) and Hintikka’s (“world-lines”). ‘God’ as a “rigid designator” is purified from all real-life-language-games of identification and only spells out a metaphysical tag, which favours the view of “anything goes”. Instead, ‘God’ as a “world-line,” plus two ways of quantification, is much more flexible to theological traditions, teachings of the church, religious practices and personal feelings. Thus, it provides a sufficiently well-defined singular term for the purposes of logical theory. The whole sketch is based on Jaakko Hintikka’s logical ideas, mainly on his responses to different authors in PJH. I have systematically omitted direct references to his texts because I have modified considerably his ideas for my own purposes.     

The notion of a recognitional concept and other confusions

The notion of a recognitional concept (RC) is stated precisely and shown to be unrelated to the proper notion of a perceptually based concept, defining of concept empiricism. More fundamentally, it is argued that the notion of an RC does not reflect a potentially sensible candidate theory of concepts at all and therefore ought to be abandoned from concept-theoretical discourse. In the later parts of the paper, it is shown independently of these points that Fodor’s attacks on RCs are in all central respects based on fallacies and confusions. Thus, even if the notion of an RC were one worth defending, it could not be threatened by Fodor’s attacks on it. Throughout the paper, I aim at clarification regarding the logical relations between various concept-theoretical options.     

A corrective to Bovens and Hartmann’s measure of coherence

Bovens and Hartmann (Bayesian Epistemology, Oxford: Oxford University Press, 2003) propose to analyze coherence as a confidence-boosting property. On the basis of this idea, they construct a new probabilistic theory of coherence. In this paper, I will attempt to show that the resulting measure of coherence clashes with some of the intuitions that motivate it. Also, I will try to show that this clash is not due to the view on coherence as a confidence-boosting property or to the general features of the model that Bovens and Hartmann use to analyze coherence. It will turn out that there is at least one other measure that is similarly based on the concept of a confidence-boosting property, but does not have the same counterintuitive results.     

Carnap,Kuhn, and revisionism: on the publication of <Emphasis Type="Italic">Structure</Emphasis> in <Emphasis Type="Italic">Encyclopedia</Emphasis>

In recent years, a revisionist process focused on logical positivism can be observed, particularly regarding Carnap’s work. In this paper, I argue against the interpretation that Kuhn’s The Structure of Scientific Revolutions having been published in the International Encyclopedia of Unified Science, co-edited by Carnap, is evidence of the revisionist idea that Carnap “would have found Structure philosophically congenial”. I claim that Kuhn’s book, from Carnap’s point of view, is not in philosophy of science but rather in history of science (in the context of a sharp discovery–justification distinction). It could also explain the fact that, despite his sympathetic letters to Kuhn as editor, Carnap never refers to Kuhn’s book in his work in philosophy of science.     

On the Possibility of Inference to the Best Explanation

Various proposals have suggested that an adequate explanatory theory should reduce the number or the cardinality of the set of logically independent claims that need be accepted in order to entail a body of data. A (and perhaps the only) well-formed proposal of this kind is William Kneale’s: an explanatory theory should be finitely axiomatizable but it’s set of logical consequences in the data language should not be finitely axiomatizable. Craig and Vaught showed that Kneale theories (almost) always exist for any recursively enumerable but not finitely axiomatizable set of data sentences in a first order language with identity. Kneale’s criterion underdetermines explanation even given all possible data in the data language; gratuitous axioms may be “tacked on.” Define a Kneale theory, T, to be logically minimal if it is deducible from every Kneale theory (in the vocabulary of T) that entails the same statements in the data language as does T. If they exist, minimal Kneale theories are candidates for best explanations: they are “bold” in a sense close to Popper’s; some minimal Kneale theory is true if any Kneale theory is true; the minimal Kneale theory that is data equivalent to any given Kneale theory is unique; and no Kneale theory is more probable than some minimal Kneale theory. I show that under the Craig-Vaught conditions, no minimal Kneale theories exist.     

Hume’s Principle and Axiom V Reconsidered: Critical Reflections on Frege and His Interpreters

In this paper, I shall discuss several topics related to Frege’s paradigms of second-order abstraction principles and his logicism. The discussion includes a critical examination of some controversial views put forward mainly by Robin Jeshion, Tyler Burge, Crispin Wright, Richard Heck and John MacFarlane. In the introductory section, I try to shed light on the connection between logical abstraction and logical objects. The second section contains a critical appraisal of Frege’s notion of evidence and its interpretation by Jeshion, the introduction of the course-of-values operator and Frege’s attitude towards Axiom V, in the expression of which this operator occurs as the key primitive term. Axiom V says that the course-of-values of the function f is identical with the course-of-values of the function g if and only if f and g are coextensional. In the third section, I intend to show that in Die Grundlagen der Arithmetik (1884) Frege hardly could have construed Hume’s Principle (HP) as a primitive truth of logic and used it as an axiom governing the cardinality operator as a primitive sign. HP expresses that the number of Fs is identical with the number of Gs if and only if F and G are equinumerous. In the fourth section, I argue that Wright falls short of making a convincing case for the alleged analyticity of HP. In the final section, I canvass Heck’s arguments for his contention that Frege knew he could deduce the simplest laws of arithmetic from HP without invoking Axiom V. I argue that they do not carry conviction. I conclude this section by rejecting an interpretation concerning HP suggested by MacFarlane.