The new regulations on xenotransplantation pay insufficient attention to the broad ethical problems raised by this technique and that the abandonment of a national body with overall regulatory authority in this area is a mistake.Following reports from the Nuffield Council on Bioethics1 and, most importantly, the Advisory Group on the Ethics of Xenotransplantation2 , the UK Xenotransplantation Interim Regulatory Authority was established in 1997. The existence of a national body to govern xenotransplantation was deemed to be of critical importance by (...) the Kennedy report given the practical and ethical issues associated with xenotransplantation. Indeed, the Kennedy report recommended that ultimately UKXIRA should be placed on a statutory footing.2 The remit of UKXIRA was to advise the Secretary of State on particular applications, gather information on issues such as safety, and assess whether the preconditions identified by the Kennedy report had been met.3In December 2006, UKXIRA was quietly disbanded, and the Department of Health issued a statement of guidance, the terms of which now govern xenotransplantation in the UK. This document superseded procedures that had been in place since 1998, which had placed the overall regulation of applications to conduct xenotransplantation in the hands of UKXIRA and, ultimately, the Secretary of State.4 The revised guidance defines xenotransplantation as being: “… any procedure that involves the transplantation, implantation, or infusion into a human recipient of either live tissues or organs retrieved from animals, or, human body fluids, cells, tissue or organs that have undergone ex vivo contact with live non-human animal cells, tissues or organs.”5 . Given the range and nature of the procedures covered by the guidance, it is surprising, not to say a little worrying, that it is so …. (shrink)

From the end of the seventeenth century to now well into the 21st, John Locke’s theory of personal identity has been foundational in the field of philosophy and psychology. Here we suggest that there are two fundamental threads intertwined in Lockean identity, the flux of perception-thought-action (i.e. continuity of consciousness) and memory. Using Maurice Merleau-Ponty, Paul Ricoeur, and Bernard Steigler as guides we will see that these threads constitute a phenomenological self (l’ésprit), a lived experience of our identity that is (...) not only perhaps the most essential component of our humanity, but also the most threatened in today’s ongoing, commercial convergence of the real and the virtual in the “Age of Disruption”. (shrink)

In his book Modal Logic as Metaphysics, Williamson argues that the traditional actualist‐possibilist debate should be abandoned as hopelessly unclear and that we should get on with the clearer contingentism‐necessitism debate. We think that Williamson’s pessimism is not warranted by the brief arguments he gives. In this paper, we explain why and provide a clear formulation of the traditional actualist‐possibilist debate.

ABSTRACT: Many of the results of Timothy Williamson's Knowledge and Its Limits depend upon his argument that many, if not all, of our mental states fail to be luminous in the sense that if we are in them, then we are in a position to know that we are in them. The purpose of this article is to show that his argument is unsound. I conclude by distinguishing between partial and total luminosity, and by arguing that even if mental (...) states are not totally luminous, they are at least partially so.RÉSUMÉ: Plusieurs des résultats du livre de Timothy Williamson, Knowledge and Its Limits dépendent de son argument à l'effet que la plupart, sinon tous nos états mentaux ne sont pas lumineux au sens où tout en se trouvant dans un tel état, nous sommes en position, de savoir que tel est notre état. Cet article a pour objectif de démontrer que ce raisonnement ne tient pas. Nous concluons par une distinction entre luminosité partielle ou complète et soutenons que, même si les états mentaux ne sont pas entièrernent clairvoyants, ils le sont en partie. (shrink)

Timothy Williamson has argued that, unless the speech act of assertion were supposed to be governed by his so-called Knowledge Rule, one could not explain why sentences of the form "A and I do not know that A" are unassertable. This paper advances three objections against that argument, of which the first two aim to show that, even assuming that Williamson's explanandum has been properly circumscribed, his explanation would not be correct, and the third aims to show that (...) his explanandum has not been properly circumscribed. (shrink)

Timothy Williamson defensa que la filosofia és una ciència teòrica que s’ocupa d’investigar sobre la realitat, d’obtenir coneixement, i que ho fa construint teories, confrontant-les amb l’evidència, d’una manera sistemàtica, disciplinada i socialment organitzada, com les altres ciències. En aquest article es compara aquesta posició, d’una banda, amb la que considera que la filosofia és una reflexió de segon ordre sobre la ciència, la moral, la política, l’art…; i, de l’altra, amb la concepció de la filosofia com a guia (...) de la vida, com a recerca de la saviesa pràctica. (shrink)

In this paper I shall argue that Tim Williamson’s argument for the anti-luminosity of many mental states faces difficult logical, psychological and epistemological problems. From a logical point of view, his argument is correct. However, the contrary argument that says that the anti-luminosity thesis does not necessarily follow from it is also correct. This opens a sceptical scenario. Hence, if Williamson wants to convince us that we should rationally prefer his argument rather than the other, he needs to (...) add considerations that are not merely logical. These are psychological and epistemological in nature. However, none of these considerations is convincing. (shrink)

Knowledge and its Limits presents a systematic new conception of knowledge as a kind of mental stage sensitive to the knower's environment. It makes a major contribution to the debate between externalist and internalist philosophies of mind, and breaks radically with the epistemological tradition of analyzing knowledge in terms of true belief. The theory casts new light on such philosophical problems as scepticism, evidence, probability and assertion, realism and anti-realism, and the limits of what can be known. The arguments are (...) illustrated by rigorous models based on epistemic logic and probability theory. The result is a new way of doing epistemology and a notable contribution to the philosophy of mind. (shrink)

Bioethicists have recently expressed concern over a lack of quality control within the field. This apprehension focuses on bioethics expanding in ways that obscure its distinctive ethical remit and the specialist reasoning skills it requires. This thesis about the quality and conduct of bioethics may have particular relevance for clinical ethics. As one of the youngest offshoots of bioethics, the field focuses on the ethical issues that arise specifically in a clinical context. However, non-ethics specialists are increasingly involved in this (...) field. This means that clinical ethics could be especially vulnerable to the quality control concerns articulated within bioethics. The growing public profile of clinical ethics means that concerns over quality in this area warrant specific attention by those concerned with declining standards in bioethics and those working in clinical ethics. (shrink)

_Identity and Discrimination_, originally published in 1990 and the first book by respected philosopher Timothy Williamson, is now reissued and updated with the inclusion of significant new material. Williamson here proposes an original and rigorous theory linking identity, a relation central to metaphysics, and indiscriminability, a relation central to epistemology.__ Updated and reissued edition of Williamson’s first publication, with the inclusion of significant new material Argues for an original cognitive account of the relation between identity and discrimination (...) that has been influential in the philosophy of perception Pioneers the use of epistemic logic to solve puzzles about indiscriminability Develops the application of techniques from mathematical logic to understand issues about identity over time and across possible worlds. (shrink)

Incapacitated and surrogateless patients are an ever-growing trend in the world of health care. Although the extent of the issue is unknown, 1 out 20 deaths in the intensive care unit (ICU) occurre...

Improbable knowing is knowing something even though it is almost certain on one’s evidence at the time that one does not know that thing. Once probabilities on the agent’s evidence are introduced into epistemic logic in a very natural way, it is easy to construct models of improbable knowing, some of which have realistic interpretations, for instance concerning agents like us with limited powers of perceptual discrimination. Improbable knowing is an extreme case of failure of the KK principle, that is, (...) of a case of knowing something even though one does not know at the time that one knows that thing. A generalization of the argument yields cases of improbable rationality, in which it is rational for one to do something even though it is almost certain on one’s evidence at the time that it is not rational for one to do that thing. When the models are elaborated to represent appearances and beliefs as well as knowledge, they turn out to contain Gettier cases. Neglect of the possibility of improbable knowing may cause some sceptical claims and claims of the non-closure of knowledge under competent deduction to look more plausible than they deserve to. A formal appendix explores the closely related question of the conditions under which a reflection principle is violated. The principle says that the evidential probability of a proposition conditional on the evidential probability of that proposition’s being c is itself c. (shrink)

The opening lines of Franz Delitzsch's Babel und Bibel offer an unusually frank confession of the personal and psychological motives that animated German orientalism in the nineteenth and early twentieth centuries. For Delitzsch and countless others like him, orientalist scholarship provided an opportunity not just to expand their knowledge of the Near East and India, but also to explore the world of the Bible and, in doing so, effect a reckoning with the religious beliefs of their childhoods. In German Orientalism (...) in the Age of Empire, Suzanne Marchand opens up this scholarly world, exploring the criss-crossing forces and interests that shaped it, while effecting her own reckoning with orientalism as a historical and historiographical phenomenon. (shrink)

The possibility of justified true belief without knowledge is normally motivated by informally classified examples. This paper shows that it can also be motivated more formally, by a natural class of epistemic models in which both knowledge and justified belief are represented. The models involve a distinction between appearance and reality. Gettier cases arise because the agent's ignorance increases as the gap between appearance and reality widens. The models also exhibit an epistemic asymmetry between good and bad cases that sceptics (...) seem to ignore or deny. (shrink)

1. What are called ‘intuitions’ in philosophy are just applications of our ordinary capacities for judgement. We think of them as intuitions when a special kind of scepticism about those capacities is salient. 2. Like scepticism about perception, scepticism about judgement pressures us into conceiving our evidence as facts about our internal psychological states: here, facts about our conscious inclinations to make judgements about some topic rather than facts about the topic itself. But the pressure should be resisted, for it (...) rests on bad epistemology: specifically, on an impossible ideal of unproblematically identifiable evidence. 3. Our resistance to scepticism about judgement is not simply epistemic conservativism, for we resist it on behalf of others as well as ourselves. A reason is needed for thinking that beliefs tend to be true. 4. Evolutionary explanations of the tendency assume what they should explain. Explanations that appeal to constraints on the determination of reference are more promising. Davidson’s truth-maximizing principle of charity is examined but rejected. 5. An alternative principle is defended on which the nature of reference is to maximize knowledge rather than truth. It is related to an externalist conception of mind on which knowing is the central mental state. 6. The knowledge-maximizing principle of charity explains why scenarios for scepticism about judgement do not warrant such scepticism, although it does not explain how we know in any particular case. We should face the fact that evidence is always liable to be contested in philosophy, and stop using talk of intuition to disguise this unpleasant truth from ourselves. (shrink)

The paper is a critique of the widespread conception of logic as a neutral arbiter between metaphysical theories, one that makes no `substantive’ claims of its own (David Kaplan and John Etchemendy are two recent examples). A familiar observation is that virtually every putatively fundamental principle of logic has been challenged over the last century on broadly metaphysical grounds (however mistaken), with a consequent proliferation of alternative logics. However, this apparent contentiousness of logic is often treated as though it were (...) neutralized by the possibility of studying all these alternative logics within an agreed metalogical framework, typically that of first-order logic with set theory. In effect, metalogic is given the role of neutral arbiter. The paper will consider a variety of examples in which deep logical disputes re-emerge at the meta-level. One case is quantified modal logic, where some varieties of actualism require a modal meta-language (as opposed to the usual non-modal language of possible worlds model theory) in order not to make their denial of the Barcan formula self-defeating. Similarly, on some views the intended model theory for second-order logic can only be given in a second-order metalanguage—this may be needed to avoid versions of Russell’s paradox when the first-order quantifiers are read as absolutely unrestricted. It can be shown that the phenomenon of higher-order vagueness eventually forces fuzzy logical treatments of vagueness to use a fuzzy metalanguage, with consequent repercussions for what first-order principles are validated. The difficulty of proving the completeness of first-order intuitionistic logic on its intended interpretation by intuitionistically rather than just classically valid means is a more familiar example. These case studies will be discussed in some detail to reveal a variety of ways in which even metalogic is metaphysically contested, substantial and non-neutral. (shrink)

The chapter argues that a model‐building methodology like that widespread in contemporary natural and social science already plays a significant role in philosophy. One neglected form of progress in philosophy over the past fifty years has been the development of better and better formal models of significant phenomena. Examples are given from both philosophy of language and epistemology. Philosophy can do still better in the future by applying model‐building methods more systematically and self‐consciously, with consequent readjustments to its methodology. Although (...) it is neither likely nor desirable for model‐building to become the sole or even main philosophical method, its use enhances the power and reliability of philosophical thinking. (shrink)

The lecture starts by considering analytic philosophy as a tradition, and its global spread over recent years, of which Disputatio’s success is itself evidence. The costs and benefits of the role of English as the international language of analytic philosophy are briefly assessed. The spread of analytic philosophy is welcomed as the best hope for scientific philosophy, in a sense of ‘science’ on which mathematics, history, and philosophy can all count as sciences, though not as natural sciences. Arguably, experimental philosophy (...) provides no plausible alternative methodology for philosophy, only a way of psychologizing it. However, it serves a useful purpose by highlighting the inadequacy of current methods for detecting errors in judgments on possible cases, which may result from reliance on possibly universal but imperfectly reliable cognitive heuristics. The problem is exacerbated by analytic philosophers’ tendency to regard increased flexibility in a theoretical framework as progress, where natural scientists would treat it as methodologically vicious profligacy with degrees of freedom. The result is a familiar type of bad science, overfitting theory to uncritically accepted data. The recent ‘hyperintensional revolution’ may be an example of such overfitting, it is suggested. The lecture ends with a call for a more miserly attitude to degrees of freedom. (shrink)

This chapter responds to Saul Kripke’s critique of the idea of adopting an alternative logic. It defends an anti-exceptionalist view of logic, on which coming to accept a new logic is a special case of coming to accept a new scientific theory. The approach is illustrated in detail by debates on quantified modal logic. A distinction between folk logic and scientific logic is modelled on the distinction between folk physics and scientific physics. The importance of not confusing logic with metalogic (...) in applying this distinction is emphasized. Defeasible inferential dispositions are shown to play a major role in theory acceptance in logic and mathematics as well as in natural and social science. Like beliefs, such dispositions are malleable in response to evidence, though not simply at will. The chapter considers the Quinean objection that accepting an alternative logic involves changing the subject rather than denying the doctrine. The objection is shown to depend on neglect of the social dimension of meaning determination, akin to descriptivism about proper names and natural kind terms criticized by Kripke and Putnam. Normal standards of interpretation indicate that disputes between classical and non-classical logicians are genuine disagreements. (shrink)

The five commentators on my paper ‘Gettier Cases in Epistemic Logic’ (GCEL) demonstrate how fruitful the topic can be. Especially in Brian Weatherson's contribution, and to some extent in those of Jennifer Nagel and Jeremy Goodman, much of the material constitutes valuable development and refinement of ideas in GCEL, rather than criticism. In response, I draw some threads together, and answer objections, mainly those in the papers by Stewart Cohen and Juan Comesaña and by Goodman.

Most of our knowledge is inexact, and known by us to be so. An example of such known inexactness will be described in some detail. The description seems to entail a contradiction. However, the paradoxical reasoning rests on an assumption. It will be suggested that the description is correct and this assumption false. Its failure will be explained by means of a picture of inexact knowledge in which the notion of a margin for error is central. This picture suggests diagnoses (...) of other paradoxical arguments: Surprise Examinations, backwards inductions about Iterated Prisoner's Dilemma, and the Heap. (shrink)

It is argued that a subject's evidence consists of all and only the propositions that the subject knows.

The core of Tony Brueckner’s critique in ‘Knowledge, Evidence, and Skepticism according to Williamson’ is his claim in section 5 that my account of perceptual knowledge has an unacceptable consequence. My reply will concentrate on that claim and largely ignore the rest of Brueckner’s interesting discussion, for it is easy to check that the claim is essential to Brueckner’s argument against my analysis of skepticism and evidence. The alleged consequence at issue concerns a case in which Brueckner knows by (...) seeing that his cup is red. According to Brueckner, I am committed to the implausible view that ‘[his] belief of the proposition that [his] cup is red is justified in virtue of [his] belief of the proposition that [his] cup is red!’ Why does he take my account of.. (shrink)

This chapter aims to attempt no more than to make some informal and unsystematic remarks on the transformation of analytic philosophy. It deals with a few sketchy remarks on the historiography of recent analytic philosophy. Writing in 1981, David Lewis described “a reasonable goal for a philosopher” as bringing one’s opinions into stable equilibrium. A natural comparison is between Lewis’s Quinean or at least post‐Quinean methodology and the methodology of Peter Strawson, Quine’s leading opponent from the tradition of ordinary language (...) philosophy. Analytic epistemology provides a good case study of the philosophical application of Gricean pragmatics outside the philosophy of language. On Michael Dummett picture of the history of philosophy, Descartes had made epistemology first philosophy, the engine for the rest of philosophy, and then Frege had replaced epistemology by the philosophy of language as first philosophy. The chapter suggests that philosophy sometimes already uses an abductive methodology and ought to use it more in the future. (shrink)

The philosophical relevance of experimental psychology is hard to dispute. Much more controversial is the so‐called negative program's critique of armchair philosophical methodology, in particular the reliance on ‘intuitions’ about thought experiments. This chapter responds to that critique. It argues that, since the negative program has been forced to extend the category of intuition to ordinary judgments about real‐life cases, the critique is in immediate danger of generating into global scepticism, because all human judgments turn out to depend on intuitions. (...) Recently, some proponents of the negative program have tried to demarcate the target of their critique more narrowly. However, their attempts are still far too indiscriminate, and over‐generate scepticism. Nevertheless, once experimental philosophy has refined its own methodology, it may contribute to the refinement of the methodology of mainstream philosophy, by filtering out the effects of cognitive bias, although it offers no prospect of doing without judgments on real or imaginary cases. (shrink)

While there are several arguments on either side, it is far from clear as to whether or not countable additivity is an acceptable axiom of subjective probability. I focus here on de Finetti's central argument against countable additivity and provide a new Dutch book proof of the principle, To argue that if we accept the Dutch book foundations of subjective probability, countable additivity is an unavoidable constraint.

Of all the cases made against classical logic, Michael Dummett's is the most deeply considered. Issuing from a systematic and original conception of the discipline, it constitutes one of the most distinctive achievements of twentieth century British philosophy. Although Dummett builds on the work of Brouwer and Heyting, he provides the case against classical logic with a new, explicit and general foundation in the philosophy of language. Dummett's central arguments, widely celebrated if not widely endorsed, concern the implications of the (...) relation between meaning and use for both the inference rules that govern logical connectives and the relation between truth and its recognition. It is less often noted that Dummett has a further argument against classical logic, one based on the semantic and set-theoretic paradoxes. That is the topic of this paper. (shrink)

Frege puzzles exploit cognitive differences between co-referential terms. Traditionally, they were handled by some version of Frege’s distinction between sense and reference, which avoided disruptive consequences for epistemology. However, the Fregean programme did not live up to its original promise, and was undermined by the development of theories of direct reference; for semantic purposes, its prospects now look dim. In particular, well-known analogues of Frege puzzles concern pairs of uncontentious synonyms; attempts to deal with them by distinguishing idiolects or postulating (...) ‘narrow contents’ or elaborate forms of context-sensitivity are inadequate or semantically implausible. Although ascriptions of knowledge, belief, and other attitudes are ubiquitous in epistemology, epistemologists have not properly come to terms with the surprising consequences of anti-Fregean semantic accounts of attitude ascriptions. In ‘A Puzzle about Belief ’, Saul Kripke shows that natural-seeming disquotational principles for ascribing belief lead to apparently unacceptable consequences, including outright contradictions, in problem cases. Such disquotation principles, I argue, are best regarded not as conceptual connections but just as heuristics in the psychological sense, quick and easy ways of assessing belief ascriptions, usually accurate under normal conditions but far from 100% reliable. I discuss similar heuristics for ascribing knowledge and other attitudes. That the principles have a merely heuristic status need not be pre-theoretically manifest to their users. This view vindicates Kripke’s conclusion that it would be wrong-headed to draw semantic conclusions from Frege puzzles. I discuss the epistemological consequences of an anti-Fregean approach to Frege puzzles, including for Kripke’s cases of the contingent a priori and the necessary a posteriori, but also for evidence, for epistemic modalities, and for epistemic and subjective conceptions of probability. Anna Mahtani’s recent identification of Frege puzzles for the ex ante Pareto Principle as used in welfare economics provides an interesting example. I suggest a model-building methodology as the most promising way of handling at least some of the difficulties. A final issue is the choice between different anti-Fregean approaches to semantics, from very coarse-grained intensional approaches on which sentences express functions from possible worlds to truth-values to more fine-grained hyperintensional approaches on which sentences express functions from possible or impossible worlds to truth-values or else Russellian structured propositions. Some of the hyperintensional theories violate semantic compositionality. More generally, since our attitude ascriptions rely on heuristics, they should be expected to exhibit some level of error; although hyperintensional approaches may be able slightly to reduce the level of postulated error, they do so at the cost of vastly increased theoretical complexity, and so have weak explanatory power. Methodologically, a simple intensional approach does better. (shrink)

Until recently, many philosophers took Causal Decision Theory to be more successful than its rival, Evidential Decision Theory. Things have changed, however, with a renewed concern that cases involving an extreme form of decision instability are counterexamples to CDT :392–403, 1984; Egan in Philos Rev 116:93–114, 2007). Most prominent among those cases of extreme decision instability is the Psychopath Button, due to Andy Egan; in that case, CDT recommends a seemingly absurd act that almost certainly results in your death. This (...) renewed attention to decision instability has spurned an array of modifications to and rejections of CDT. I argue, however, that the Psychopath Button and its ilk are no counterexamples to CDT. That is, given the causalist’s commitments in Newcomb Problems, they already have the tools to justify CDT’s verdict in Egan-style cases of extreme decision instability. I first argue that there is no reason to think the Psychopath Button is a counterexample to CDT; in particular, many philosophers have placed too much weight on pre-theoretic intuition in Egan-cases, and apart from pre-theoretic intuition, arguments against CDT in cases of extreme decision instability are flawed. My second claim is that the causalist can provide good reasons for following CDT in cases of extreme decision instability. I present a new case, the Two Button Defense, that highlights precisely why the causalist can reasonably follow CDT in even the Psychopath Button. CDT therefore stands as a viable decision theory, without need for modification, restriction, or rejection. (shrink)

There is a constant temptation in philosophy to postulate a realm of phenomena in which nothing is hidden from us. Rene Descartes thought that one's own mind is such a realm. Ludwig Wittgenstein' enlarged the realm to everything that is of interest to philosophy. That they explained this special feature in very different ways hardly needs to be said; what is remarkable is their agreement on our possession of a cognitive home in which everything lies open to our view. Much (...) of our thinking – for example, in the physical sciences – must operate outside this home, in alien circumstances. The claim is that not all our thinking could be like that. (shrink)

Russo and Williamson (Int Stud Philos Sci 21(2):157–170, 2007) put forward the thesis that, at least in the health sciences, to establish the claim that C is a cause of E, one normally needs evidence of an underlying mechanism linking C and E as well as evidence that C makes a difference to E. This epistemological thesis poses a problem for most current analyses of causality which, in virtue of analysing causality in terms of just one of mechanisms or (...) difference making, cannot account for the need for the other kind of evidence. Weber (Int Stud Philos Sci 23(2):277–295, 2009) has suggested to the contrary that Giere’s probabilistic analysis of causality survives this criticism. In this paper, we look in detail at the case of medical imaging technology, which, we argue, supports the thesis of Russo and Williamson, and we respond to Weber’s suggestion, arguing that Giere’s account does not survive the criticism. (shrink)

We argue that David Lewis’s principal principle implies a version of the principle of indifference. The same is true for similar principles that need to appeal to the concept of admissibility. Such principles are thus in accord with objective Bayesianism, but in tension with subjective Bayesianism. 1 The Argument2 Some Objections Met.

The paper explains how Gettier’s conclusion can be reached on general theoretical grounds within the framework of epistemic logic, without reliance on thought experiments. It extends the argument to permissive conceptions of justification that invalidate principles of multi-premise closure and require neighbourhood semantics rather than semantics of a more standard type. The paper concludes by recommending a robust methodology that aims at convergence in results between thought experimentation and more formal methods. It also warns against conjunctive definitions as sharing several (...) of the drawbacks of disjunctive definitions. (shrink)

The Recursive Bayesian Net (RBN) formalism was originally developed for modelling nested causal relationships. In this paper we argue that the formalism can also be applied to modelling the hierarchical structure of mechanisms. The resulting network contains quantitative information about probabilities, as well as qualitative information about mechanistic structure and causal relations. Since information about probabilities, mechanisms and causal relations is vital for prediction, explanation and control respectively, an RBN can be applied to all these tasks. We show in particular (...) how a simple two-level RBN can be used to model a mechanism in cancer science. The higher level of our model contains variables at the clinical level, while the lower level maps the structure of the cell's mechanism for apoptosis. (shrink)

Audi explains what he means by ‘normative’ in the case of belief: cognitive (epistemic) normativity is a matter of what ought to be believed, where the force of the “ought” is in part to attribute liability to criticism and negative (disapproving) attitudes toward the person(s) in question.

A theory of evidential probability is developed from two assumptions:(1) the evidential probability of a proposition is its probability conditional on the total evidence;(2) one's total evidence is one's total knowledge. Evidential probability is distinguished from both subjective and objective probability. Loss as well as gain of evidence is permitted. Evidential probability is embedded within epistemic logic by means of possible worlds semantics for modal logic; this allows a natural theory of higher-order probability to be developed. In particular, it is (...) emphasized that it is sometimes uncertain which propositions are part of one's total evidence; some surprising implications of this fact are drawn out. (shrink)

The paper responds to Neil Tennant's recent discussion of Fitch's so-called paradox of knowability in the context of intuitionistic logic. Tennant's criticisms of the author's earlier work on this topic are shown to rest on a principle about the assertability of disjunctions with the absurd consequence that everything we could make true already is true. Tennant restricts the anti-realist principle that truth implies knowability in order to escape Fitch's argument, but a more complex variant of the argument is shown to (...) elicit from his restricted principle exactly the consequences which it was intended to avoid. (shrink)

Schurz (2019, ch. 4) argues that probabilistic accounts of induction fail. In particular, he criticises probabilistic accounts of induction that appeal to direct inference principles, including subjective Bayesian approaches (e.g., Howson 2000) and objective Bayesian approaches (see, e.g., Williamson 2017). In this paper, I argue that Schurz’ preferred direct inference principle, namely Reichenbach’s Principle of the Narrowest Reference Class, faces formidable problems in a standard probabilistic setting. Furthermore, the main alternative direct inference principle, Lewis’ Principal Principle, is also hard (...) to reconcile with standard probabilism. So, I argue, standard probabilistic approaches cannot appeal to direct inference to explicate the logic of induction. However, I go on to defend a non-standard objective Bayesian account of induction: I argue that this approach can both accommodate direct inference and provide a viable account of the logic of induction. I then defend this account against Schurz’ criticisms. (shrink)

Rational thinkers respect their evidence. Properly understood, that is a platitude. But how can one respect one's evidence unless one knows what it is? So must not rational thinkers know what their evidence is?

Being social creatures in a complex world, we do things together. We act jointly. While cooperation, in its broadest sense, can involve merely getting out of each other’s way, or refusing to deceive other people, it is also essential to human nature that it involves more active forms of collaboration and coordination (Tomasello 2009; Sterelny 2012). We collaborate with others in many ordinary activities which, though at times similar to those of other animals, take unique and diverse cultural and psychological (...) forms in human beings. But we also work closely and interactively with each other in more peculiar and flexible practices which are in distinctive ways both species-specific and culturally and historically contingent: from team sports to shared labour, from committee work to mass demonstrations, from dancing to reminiscing together about old times. (shrink)

Contextualism is relativism tamed. Relativism about truth is usually motivated by the idea of no-fault disagreement. Imagine two parties: one (she) says ‘P’; the other (he) says ‘Not P’.1 Apparently, if P then ‘P’ is true and ‘Not P’ false, so she is right and he is wrong; if not P then ‘P’ is false and ‘Not P’ true, so he is right and she is wrong. In both cases, there is an asymmetry between the two parties. Since P or (...) not P (by the law of excluded middle), there is indeed an asymmetry between them, one way or the other. Yet the two parties may strike a neutral observer as on a par, equally intelligent, informed, perceptive and alert. Relativists about truth strive to dissolve the unpleasant asymmetry: ‘”P” is true for her; “Not P” is true for him’. Trouble starts when we ask what the relativists mean by ‘for’ in the construction ‘true for X’. If to call something true ‘for’ X is just to say that X believes that it is true, then the attempted dissolution amounts to this: ‘She believes that “P” is true; he believes that “Not P” is true’. But that is to add no more than that both parties believe that they are right; it does nothing to undermine the argument for an asymmetry between them. Relativists had better mean something else by ‘true for X’. When asked to explain what else they mean, wild relativists bluster incoherently. Contextualists, by contrast, have a clear answer. A sentence is true for X if and only if it is true as uttered by X, true relative to a context in which X is the speaker. Such relativism is tame because the relativity to context in the truth-value of a sentence allows for absoluteness in the truth-value of what the sentence is used to say in a given context. When she says ‘P’, she speaks truly: not just truly for her, but absolutely truly. When he says ‘Not P’, he too speaks truly: not just truly for him, but absolutely truly. The argument for asymmetry 1 assumes that, when she says ‘P’, she speaks truly if and only if P, and when he says ‘Not P’, he speaks truly if and only if not P.. (shrink)

The main result of this paper is that KT is closed under a cancellation principle. This result extends to KTG1, but it does not extend to modal systems associated with the provability interpretation of L, such as KW and KT4Grz. Following Williamson, these results are applied to philosophical concerns about the proper form for theories of meaning, via the interpretation of L as some kind of veriflability. The cancellation principle can then be read as saying that verifilability conditions and (...) falsiflability conditions jointly determine truth conditions. (shrink)

The epistemic theory of causality is analogous to epistemic theories of probability. Most proponents of epistemic probability would argue that one's degrees of belief should be calibrated to chances, insofar as one has evidence of chances. The question arises as to whether causal beliefs should satisfy an analogous calibration norm. In this paper, I formulate a particular version of a norm requiring calibration to chances and argue that this norm is the most fundamental evidential norm for epistemic probability. I then (...) develop an analogous calibration norm for epistemic causality, argue that it is the *only* evidential norm required for epistemic causality, and show how an epistemic account of causality that incorporates this norm can be used to analyse objective causal relationships. (shrink)

I put forward several desiderata that a philosophical theory of causality should satisfy: it should account for the objectivity of causality, it should underpin formalisms for causal reasoning, it should admit a viable epistemology, it should be able to cope with the great variety of causal claims that are made, and it should be ontologically parsimonious. I argue that Nancy Cartwright’s dispositional account of causality goes part way towards meeting these criteria but is lacking in important respects. I go on (...) to argue that my epistemic account, which ties causal relationships to an agent’s knowledge and ignorance, performs well in the light of the desiderata. Such an account, I claim, is all we require from a theory of causality. (shrink)

I. An argument is presented for the conclusion that the hypothesis that no one will ever decide a given proposition is intuitionistically inconsistent. II. A distinction between sentences and statements blocks a similar argument for the stronger conclusion that the hypothesis that I have not yet decided a given proposition is intuitionistically inconsistent, but does not block the original argument. III. A distinction between empirical and mathematical negation might block the original argument, and empirical negation might be modelled on Nelson''s (...) strong negation, but only on intuitionistically unacceptable assumptions. IV. Intuitionists may have to accept the original argument, and therefore be committed to a dubious view of time on which there cannot be merely inductive evidence for statements about the infinite future. (shrink)