Kaplan (drawing on Montague and Prior, inter alia) made explicit the idea of world and time neutral propositions, which bear truth values only relative to world and time parameters. There was then a debate over the role of time. Temporalists sided with Kaplan in maintaining time neutral propositions with time relative truth values, while eternalists claimed that all propositions specify the needed time information and so bear the same truth value at all times. But there never was (...) much of a parallel debate over the role of worlds. Let contingentism be the view (parallel to temporalism) that sides with Kaplan in maintaining world neutral propositions with world relative truth values, and let necessitarianism be the view (parallel to eternalism) that propositions specify the needed world information and so bear the same truth value at all worlds. This is the story of how the debate between the contingentists and the necessitarians might begin. (shrink)

Parallel lives is a model which provides an interpretation of quantum theory that is both local and realistic. This model assumes that all quantum fields are composed of point beings called “lives”. Lives interact locally and have a memory of their previous interactions. The reduction of the state vector is not included in this model: lives can be divided into different worlds. This feature resembles many worlds interpretation. However in the parallel lives model, the division of lives into (...) different worlds takes place locally. The parallel lives model is expected to be compatible with special relativity, as the lives propagate at a speed that does not exceed the speed of light and interact locally. On the other hand, it is open to paradoxes based on counterfactual propositions, as it provides a realistic interpretation of quantum theory. In this paper, we confront the parallel lives model with the paradox proposed by Hardy. We show that the parallel lives model cannot overcome the dilemma in Hardy’s paradox. We discuss implications of this confrontation on special theory of relativity, and speculate a solution that we believe, fits the spirit of the parallel lives model. (shrink)

An important objection to sententialist theories of attitude reports is that they cannot accommodate the principle that one cannot know that someone believes that p without knowing what it is that he believes. This paper argues that a parallel problem arises for propositionalist accounts that has gone largely unnoticed, and that, furthermore, the usual resources for the propositionalist do not afford an adequate solution. While non-standard solutions are available for the propositionalist, it turns out that there are parallel (...) solutions that are available for the sententialist. Since the difficulties raised seem to show that the mechanism by which sentential complements serve to inform us about attitudes and about sentence meaning does not depend on their referring to propositions, this casts doubt on whether talk of propositions should retain a significant theoretical role in the enterprise of understanding thought, language and communication. (shrink)

The splitting theorem says that any set of formulae has a finest representation as a family of letter-disjoint sets. Parikh formulated this for classical propositional logic, proved it in the finite case, used it to formulate a criterion for relevance in belief change, and showed that AGMpartial meet revision can fail the criterion. In this paper we make three further contributions. We begin by establishing a new version of the well-known interpolation theorem, which we call parallel interpolation, use it (...) to prove the splitting theorem in the infinite case, and show how AGM belief change operations may be modified, if desired, so as to ensure satisfaction of Parikh’s relevance criterion. (shrink)

An important question in epistemology concerns how the two species of justification, propositional and doxastic justification, are related to one another. According to the received view, basing one’s belief p on the grounds that provide propositional justification to believe p is sufficient for the belief to be doxastically justified. In a recent paper, however, John Turri has suggested that we should reverse the direction of explanation. In this paper, I propose to see the debate in a new light by suggesting (...) that the best way to understand the relationship between these species of justification is by viewing propositional justification as an dispositional property that a subject can have with doxastic justification as its manifestation. I show how the debate in metaphysics over the question of how disposition statements should be analyzed runs parallel to the epistemological debate, and bring some of the results in the dispositions debate to bear on the epistemological question. I end by offering some tentative remarks regarding the order of priority of these two species of justification. (shrink)

It is our contention that an ontological commitment to propositions faces a number of problems; so many, in fact, that an attitude of realism towards propositions—understood the usual “platonistic” way, as a kind of mind- and language-independent abstract entity—is ultimately untenable. The particular worries about propositions that marshal parallel problems that Paul Benacerraf has raised for mathematical platonists. At the same time, the utility of “proposition-talk”—indeed, the apparent linguistic commitment evident in our use of 'that'-clauses (in (...) offering explanations and making predictions)—is also in need of explanation. We account for this with a fictionalist analysis of our use of 'that'-clauses. Our account avoids certain problems that arise for the usual error-theoretic versions of fictionalism because we apply the notion of semantic pretense to develop an alternative, pretense-involving, non-error-theoretic, fictionalist account of proposition-talk. (shrink)

We describe the constructive content of proofs in a fragment of propositional Infinitary Linear Logic in terms of strategies for a suitable class of games. Such strategies interpret linear proofs as parallel algorithms as long as the asymmetry of the connectives ? and ! allows it.

Argument that Q∃ expresses more than one proposition: (1) Q∃ expresses the proposition that Q∃ expresses some proposition that isn’t true. ((E)) (2) If Q ∃ expresses only true propositions, then the proposition that Q ∃ expresses some proposition that isn’t true is true. ((1)) (3) If Q∃ expresses only true propositions, then some proposition expressed by Q∃ is not true. (2, T) (4) Some proposition expressed by Q ∃ is not true. ((3)) (5) The proposition that Q (...) ∃ expresses some proposition that isn’t true is true. (4, T) (6) Q∃ expresses at least one true proposition. (1,5) (7) Q∃ expresses at least two propositions. (3, 6) (A parallel argument shows that Q∀ expresses both true and false propositions. (shrink)

This paper defends a key aspect of the Peircean conception of truth—the idea that truth is in some sense epistemically-constrained. It does so by exploring parallels between Peirce’s epistemology of inquiry and that of Wittgenstein in On Certainty. The central argument defends a Peircean claim about truth by appeal to a view shared by Peirce and Wittgenstein about the structure of reasons. This view relies on the idea that certain claims have a special epistemic status, or function as what are (...) popularly called ‘hinge propositions’. (shrink)

Natural deduction systems were motivated by the desire to define the meaning of each connective by specifying how it is introduced and eliminated from inference. In one sense, this attempt fails, for it is well known that propositional logic rules underdetermine the classical truth tables. Natural deduction rules are too weak to enforce the intended readings of the connectives; they allow non-standard models. Two reactions to this phenomenon appear in the literature. One is to try to restore the standard readings, (...) for example by adopting sequent rules with multiple conclusions. Another is to explore what readings the natural deduction rules do enforce. When the notion of a model of a rule is generalized, it is found that natural deduction rules express “intuitionistic” readings of their connectives. A third approach is presented here. The intuitionistic readings emerge when models of rules are defined globally, but the notion of a local model of a rule is also natural. Using this benchmark, natural deduction rules enforce exactly the classical readings of the connectives, while this is not true of axiomatic systems. This vindicates the historical motivation for natural deduction rules. One odd consequence of using the local model benchmark is that some systems of propositional logic are not complete for the semantics that their rules express. Parallels are drawn with incompleteness results in modal logic to help make sense of this. (shrink)

Contemporary epistemology has assumed that knowledge is represented in sentences or propositions. However, a variety of extensions and alternatives to this view have been proposed in other areas of investigation. We review some of these proposals, focusing on (1) Ryle's notion of knowing how and Hanson's and Kuhn's accounts of theory-laden perception in science; (2) extensions of simple propositional representations in cognitive models and artificial intelligence; (3) the debate concerning imagistic versus propositional representations in cognitive psychology; (4) recent treatments (...) of concepts and categorization which reject the notion of necessary and sufficient conditions; and (5) parallel distributed processing (connectionist) models of cognition. This last development is especially promising in providing a flexible, powerful means of representing information nonpropositionally, and carrying out at least simple forms of inference without rules. Central to several of the proposals is the notion that much of human cognition might consist in pattern recognition rather than manipulation of rules and propositions. (shrink)

We show that (contrary to the parallel case of intuitionistic logic, see [7], [4]) there does not exist a translation fromS42 (the propositional modal systemS4 enriched with propositional quantifiers) intoS4 that preserves provability and reduces to identity for Boolean connectives and.

RésuméDans son analyse des propositions hypothétiques, conditionnelles et disjonctives, Ibn Sīnā suggère que ces propositions peuvent être quantifiées et présente dans la section VI de son traité un système hypothétique contenant les propositions conditionnelles, qui est exactement parallèle à la syllogistique des propositions catégoriques et utilise les mêmes règles de conversion et les mêmes démonstrations. Dans la section VII, il présente quatre listes de propositions hypothétiques quantifiées dont les composants sont eux-mêmes quantifiés et affirme que (...) les relations du carré aristotélicien des oppositions valent pour ces propositions. Par ailleurs, il affirme que certaines propositions conditionnelles universelles affirmatives sont équivalentes à certaines universelles négatives dont les conséquents sont opposés, et également à certaines propositions disjonctives. Le problème est que ces thèses sont incompatibles entre elles, car elles requièrent deux lectures différentes de la proposition conditionnelle universelle affirmative, qu'Ibn Sīnā ne distingue pas clairement. Dans le présent article nous résolvons le problème en distinguant explicitement entre ces deux interprétations et en montrant que la première valide la conversion de l'universelle affirmative et les relations du carré des oppositions ainsi que tous les modes admis, alors que la seconde valide la règle de contraposition et les équivalences énoncées par Ibn Sīnā, ce qui rend compte des affirmations d'Ibn Sīnā et rend le système cohérent. (shrink)

The aim of being able to reason about quantities, time or space has been the main objective of the many efforts on the integration of propositional planning with extensions to handle different theories. Planning modulo theories are an approximation inspired by satisfiability modulo theories that generalize the integration of arbitrary theories with propositional planning. Parallel plans are crucial to reduce plan lengths and hence the time needed to reach a feasible plan in many approaches. Parallelization of actions relies on (...) the notion of interference, which is usually determined syntactically at compile time. In this paper we define a semantic notion of interference between actions in PMT. Apart from being strictly stronger than any syntactic notion of interference, we show how semantic interference can be easily and efficiently checked by calling an off-the-shelf SMT solver at compile time, constituting a technique orthogonal to the solving method. (shrink)

There are parallels between certain responses to local epistemological scepticism about religious belief and an influential reply to radical epistemological scepticism. What ties both accounts together is that they utilise, either implicitly or explicitly, a “hinge” proposition thesis which maintains that the pivotal beliefs in question are immune to sceptical attack even though they lack sufficient epistemic grounds. It is argued that just as this strategy lacks any anti-sceptical efficacy in the context of the radical sceptical debate, so it offers (...) no defence against a localised scepticism regarding religious belief either. What the defender of religious belief should do, it is claimed, is re-examine the manner in which a commitment to the doctrine of epistemological internalism underlies the sceptical attack. (shrink)

I draw attention to a 12-page Vorarbeit to Kant’s Prolegomena from the so-called Scheffner-Nachlaß and argue that the parallel Kant draws there between the possibility of theoretical and practical synthetic a priori propositions provides important insight into the development of his account of practical autonomy in the Groundwork. Based on a brief sketch of the role synthetic a priori propositions play in the development of Kant’s critical philosophy, I conclude that for Kant the objective validity of any (...) science depends on the objective validity of a number of synthetic a priori propositions. (shrink)

In at least some cases of future directed propositional hoping, facts about the hoper become puzzling if one supposes that the object of hoping is a future tensed proposition. These facts are easily explained by the alternative suppostion that the hoper accepts a future tensed proposition but bears the hopingattitude toward a disjunctively tensed proposition. Parallel remarks apply to past directed and present directed prepositional hoping. Thus, at least some instances of hoping have as their objects disjunctively tensed rather (...) than purely tensed propositions. Propositional remembering may possibly resemblepropositional hoping in this respect. (shrink)

Several authors assume that evaluative conditioning (EC) relies on high-level propositional thinking. In contrast, the dual-process perspective proposes two processing pathways, one associative and the other propositional, contributing to EC. Dual-process theorists argue that attitudinal ambiguity resulting from these two pathways’ conflicting evaluations demonstrate the involvement of both automatic and controlled processes in EC. Previously, we suggested that amplitude variations of error-related negativity and error-positivity, two well-researched event-related potentials of performance monitoring, allow for the detection of attitudinal ambiguity at the (...) neural level. The present study utilises self-reported evaluation, categorisation performance, and neural correlates of performance monitoring to explore associative-propositional ambiguity during social attitude formation. Our results show that compared to associative-propositional harmony, attitudinal ambiguity correlates with more neutral subjective evaluations, longer response times, increased error commission, and diminished error-related negativity amplitudes. While our findings align with dual-process models, we aim to offer a propositional interpretation. We discuss dual-process theories in the context of evolutionary psychology, suggesting that associative processes may only represent a small piece of the EC puzzle. (shrink)

In this paper we show that some versions of Dung’s abstract argumentation frames are equivalent to classical propositional logic. In fact, Dung’s attack relation is none other than the generalised Peirce–Quine dagger connective of classical logic which can generate the other connectives ${\neg, \wedge, \vee, \to}$ of classical logic. After establishing the above correspondence we offer variations of the Dung argumentation frames in parallel to variations of classical logic, such as resource logics, predicate logic, etc., etc., and create resource (...) argumentation frames, predicate argumentation frames, etc., etc. We also offer the notion of logic proof as a geometrical walk along the nodes of a Dung network and thus we are able to offer a geometrical abstraction of the notion of inference based argumentation. Thus our paper is also a contribution to the question: “What is a logical system” in as much as it integrates logic with abstract argumentation networks. (shrink)

In this article we explore how two enactments of HIV – the UN’s AIDS Clock and clinical trials for an HIV biomedical prevention technology or pre-exposure prophylaxis – entail particular globalizing and localizing dynamics. Drawing on Latour’s and Whitehead’s concept of proposition, and Serres’ call for a philosophy of prepositions, we use the composite notion of pre/pro-positions to trace the shifting topological status of HIV. For example, we show how PrEP emerges through topological entwinements of globalizing biomedical standardization, localizing protests (...) against PrEP trials and globalizing ethical principles. We go on to examine how our own analysis manifests a parallel topological pattern in which we deploy a globalizing argument about the localizing of the globalizing found in the AIDS Clock and the PrEP trails. Finally, we consider how the movement of ‘topology’ into the social sciences might itself benefit from a topological treatment. (shrink)

Bolzano's position on logic and his theory of sentences-in-themselves and their analysis, as well as his position on existence statements and subjective representations show a striking and profound similarity to Frege's theory of thoughts, his analysis of propositions, representations and judgment, as well as his position on the nature of logic in general. Bolzano's theories on these points, therefore, may well have been seminal to the development of Frege's position.

In at least some cases of future directed propositional hoping, facts about the hoper become puzzling if one supposes that the object of hoping is a future tensed proposition. These facts are easily explained by the alternative suppostion that the hoper accepts a future tensed proposition but bears the hopingattitude toward a disjunctively tensed proposition. Parallel remarks apply to past directed and present directed prepositional hoping. Thus, at least some instances of hoping have as their objects disjunctively tensed rather (...) than purely tensed propositions. Propositional remembering may possibly resemblepropositional hoping in this respect. (shrink)

In contrast with some recent theories of infinitesimals as non-Archimedean entities, Leibniz’s mature interpretation was fully in accord with the Archimedean Axiom: infinitesimals are fictions, whose treatment as entities incomparably smaller than finite quantities is justifiable wholly in terms of variable finite quantities that can be taken as small as desired, i.e. syncategorematically. In this paper I explain this syncategorematic interpretation, and how Leibniz used it to justify the calculus. I then compare it with the approach of Smooth Infinitesimal Analysis (...) (SIA), as propounded by John Bell. Despite many parallels between SIA and Leibniz’s approach —the non-punctiform nature of infinitesimals, their acting as parts of the continuum, the dependence on variables (as opposed to the static quantities of both Standard and Non-standard Analysis), the resolution of curves into infinitesided polygons, and the finessing of a commitment to the existence of infinitesimals— I find some salient differences, especially with regard to higher-order infinitesimals. These differences are illustrated by a consideration of how each approach might be applied to Newton’s Proposition 6 of the Principia, and the derivation from it of the v2/r law for the centripetal force on a body orbiting around a centre of force. It is found that while Leibniz’s syncategorematic approach is adequate to ground a Leibnizian version of the v2/r law for the “solicitation” ddr experienced by the orbiting body, there is no corresponding possibility for a derivation of the law by nilsquare infinitesimals; and while SIA can allow for second order differentials if nilcube infinitesimals are assumed, difficulties remain concerning the compatibility of nilcube infinitesimals with the principles of SIA, and in any case render the type of infinitesimal analysis adopted dependent on its applicability to the problem at hand. (shrink)

The distinction between propositional and doxastic justification is normally applied to belief. The goal of this paper is to apply the distinction to faith and hope. Before doing so, I discuss the nature of faith and hope, and how they contrast with belief—belief has no essential conative component, whereas faith and hope essentially involve the conative. I discuss implications this has for evaluating faith and hope, and apply this to the propositional/doxastic distinction. There are two key upshots. One, bringing in (...) faith and hope makes salient additional normative categories, including the way the distinction between epistemic and practical justification interacts with the distinction between propositional and doxastic justification. Two, a paradigm example of propositional without doxastic justification is a belief that is evidentially supported but based on wishful thinking. Surprisingly, parallel cases of faith and hope may actually enjoy both propositional and doxastic justification. I conclude by exploring what it might look like for faith and hope to have propositional justification without doxastic justification. (shrink)

Doctors and dentists have traditionally used antibiotic prophylaxis in certain patient groups in order to prevent infective endocarditis (IE). New guidelines, however, suggest that the risk to patients from using antibiotics is higher than the risk from IE. This paper analyses the relative risks of prescribing and not prescribing antibiotic prophylaxis against the background of Pascal’s Wager, the infamous assertion that it is better to believe in God regardless of evidence, because of the prospective benefits should He exist. Many doctors (...) seem to believe the parallel proposition that it is better to prescribe antibiotics, regardless of evidence, because of the prospective benefit conferred upon the patient. This has been called the “no lose philosophy” in medicine: better safe than sorry, even if the evidence inconveniently suggests that following this mantra is potentially more likely to result in sorry than safe. It transpires that, just as Pascal’s Wager fails to convince because of a lack of evidence to support it and the costs incurred by trying to believe, so the “belts and braces” approach of prescribing antibiotic prophylaxis is unjustifiable given the actual evidence of potential risk and benefit to the patient. Ultimately, there is no no-lose if your clinical decisions, like Pascal’s Wager, are based on faith rather than evidence. (shrink)

I intended to write four papers whose topics faintly concerned separate issues in meaning and modality. As it turned out, chapters 1-3 all roughly concern the same topic: propositions. While I argue for two different theses in chapters 1 and 2, I try to understand the changing propositions literature in both. In addition to arguing for the respective theses in chapters 1 and 2, accounting for this change is a parallel goal for the chapters taken together. Chapter (...) 3 examines particular propositional roles---the objects of the attitudes and the objects of credence. Finally, chapter 4 changes the subject to the second conjunct in the title---modality, specifically of the epistemic kind. (shrink)

In diesem Aufsatz argumentiere ich, dass die Standardauffassung von Propositionen und propositionalen Einstellungen inadäquat ist, ein Artefakt der gegenwärtig herrschenden theorielastigen Auffassung von Intentionalität, Sprache und Rationalität, und skizziere eine alternative Auffassung. Im folgenden Abschnitt belege ich erst einmal die These der Theorielastigkeit anhand einiger Beispiele vor allem aus der gegenwärtigen analytischen Philosophie. Der dritte Abschnitt erklärt, wie diese Theorielastigkeit im Standardverständnis von Propositionen und propositionalen Einstellungen verkörpert ist. Im vierten Abschnitt argumentiere ich, dass dieses Standardverständnis der Proposition zwei unvereinbare (...) Rollen zuweist. Sie kann nicht sowohl einen Sachverhalt repräsentieren, der Gegenstand praktischer genauso wie theoretischer Stellungnahmen sein kann, als auch wie eine theoretische Stellungnahme Wahrheitswertträger sein. In den folgenden Abschnitten versuche ich eine partielle Diagnose, wie es zu dieser Auffassung kommen kann: gewisse Formen der Neutralisierung von Stellungnahmen durch das bloße „in den Raum stellen“ (fünfter Abschnitt), durch fiktionale Kontexte (sechster Abschnitt) und den Kontext logischer Verknüpfungen (der so genannte „Frege-Punkt“; siebter Abschnitt) werden verwechselt mit der Neutralität zwischen dem Praktischen und Theoretischen, zwischen Wollen und Wahrheit, die die Standardauffassung erfordern würde. Der achte Abschnitt skizziert in groben Umrissen ein alternatives Bild. Demnach wird eine Repräsentation eines Sachverhalts erst durch die dazu kommende theoretische oder praktische Position zu einer Stellungnahme und damit zum Träger eines Erfüllungswerts. Die Bereiche des Praktischen und des Theoretischen sind parallel strukturiert und unterschieden sich im Wesentlichen nur durch die Verschiedenheit der Passrichtungen. Grundlegende rationale Operationen wie Deduktion, Abduktion und Induktion können auf praktischen Stellungnahmen genauso ausgeführt werden wie auf theoretischen. Im neunten Abschnitt verorte ich die tieferen Wurzeln der Theorielastigkeit in dem Verlangen, das Praktische an die dem Theoretischen eigene Form der Objektivität zu assimilieren. Dieses Verlangen muss aber fruchtlos bleiben, und die dem Praktischen eigene Form der Objektivität wird so verfehlt. Der letzte Abschnitt deutet an, wie sich Werturteile in dem skizzierten Rahmen deuten lassen. (shrink)

The paper presents a logical treatment of actions based on dynamic logic. This approach makes it possible to reflect clearly the differences between static and dynamic elements of the world, a distinction which seems crucial to us for a representation of actions.Starting from propositional dynamic logic a formal system (DLA) is developed, the programs of which are used to model action types. Some special features of this system are: Basic aspects of time are incorporated in DLA as far as they (...) are needed for our purpose. Names for states and for instants are simulated by formulas. It is possible to express formally that a formula is satisfiable or valid. A special program is introduced to reflect developments which are not caused by an official agent but by external influences. (shrink)

In the debate between literalism and contextualism in semantics, Kent Bach’s project is often taken to stand on the latter side of the divide. In this paper I argue that this is a misleading assumption and justify this by contrasting Bach’s assessment of the theoretical eliminability of minimal propositions arguably expressed by well-formed sentences with standard minimalist views, and by further contrasting his account of the division of interpretative processes ascribable to the semantics and pragmatics of a language with (...) a parallel analysis carried out by the most radical opponent to semantic minimalism, i.e., by occasionalism. If my analysis proves right, the sum of its conclusions leaves Bach’s proposal in an invisible region of the literalism/contextualism debate. (shrink)

There are close parallels between Frank Jackson's case of black-and-white Mary and David Lewis's case of the two omniscient gods. This essay develops and defends what may be called “the ability hypothesis” about the knowledge that the gods lack, by adapting Lewis's ability hypothesis about the knowledge that Mary acquires. What the gods might lack despite their propositional omniscience is not any distinctive kind of information, but certain abilities of introspection. The motivating idea is that knowledge one acquires by exercising (...) introspective abilities cannot fail to be knowledge about oneself or indexical knowledge. So in order to envisage the gods' epistemic situation coherently, we need to assume that they lack those introspective abilities. But once we recognize that, it turns out that positing a special kind of information is a gratuitous addition. The two gods' ignorance simply consists in their lack of introspective abilities. (shrink)

This article further explains and develops a recent, comprehensive semantic naturalization theory, namely the interactive indexing (II) theory as described in my 2008 Minds and Machines article Semantic Naturalization via Interactive Perceptual Causality (Vol. 18, pp. 527–546). Folk views postulate a concrete intentional relation between cognitive states and the worldly states they are about. The II theory eliminates any such concrete intentionality, replacing it with purely causal relations based on the interactive theory of perception. But intentionality is preserved via purely (...) abstract propositions about the world that index, or correlate with, appropriate cognitive states. Further reasons as to why intentionality must be abstract are provided, along with more details of an II-style account of representation, language use and propositional attitudes. All cognitive representation is explained in terms of classification or sorting dispositions indexed by appropriate propositions. The theory is also related to Fodor’s representational theory of mind, with some surprisingly close parallels being found in spite of the purely dispositional basis of the II theory. In particular, Fodor’s insistence that thinking about an item cannot be reduced to sorting dispositions is supported via a novel two-level account of cognition—upper level propositional attitudes involve significant intermediate processing of a broadly normative epistemic kind prior to the formation of sorting dispositions. To conclude, the weak intentional realism of the II theory—which makes intentional descriptions of the world dispensable—is related to Dennett’s ‘intentional stance’ view, and distinguished from strong (indispensable) intentional realist views. II-style dispositions are also defended. (shrink)

Bertrand Russell’s 1906 article ‘The Theory of Implication’ contains an algebraic weak completeness proof for classical propositional logic. Russell did not present it as such. We give an exposition of the proof and investigate Russell’s view of what he was about, whether he could have appreciated the proof for what it is, and why there is no parallel of the proof in Principia Mathematica.

Something remarkable is happening in the cognitive sciences. After a quarter of a century of cognitive models that were inspired by the metaphor of the digital computer, the newest cognitive models are inspired by the properties of the brain itself. Variously referred to as connectionist, parallel distributed processing, or neutral network models, they explore the idea that complex intellectual operations can be carried out by large networks of simple, neuron-like units. The units themselves are identical, very low-level and 'stupid'. (...) Intelligent performance is derived from the pattern of connection strengths between units, and the fundamental cognitive activity is pattern recognition and completion. Connectionism and the Mind provides an introduction to this newly emerging approach to understanding the mind. The first few chapters focus on network architecture, offering accessible treatment of the equations that describe learning and the propagation of activation. Furthermore, the reader is walked step-by-step through the activities of networks engaged in pattern recognition, learning, and cognitive tasks such as memory retrieval and prototype formation. The remainder of the book addresses the implications of connectionism for theories of the mind, both philosophical and psychological. Foe example: What Role is played by pattern recognition and completion as basic as cognitive functions? Connectionist models have particular strength in learning and pattern recognition; should they be limited to those functions, or can they provide an overall account of cognitive functioning? In particular, can connectionist models provide an adequate account of the ability to employ linguistic and other symbol systems, or must an adequate system incorporate symbol processing as a basic cognitive capacity? Finally, Connectionism and the Mind examines the relation of connectionist models to philosophical accounts of propositional attitudes, and to a variety of other inquiries in cognitive psychology, linguistics, developmental psychology, artificial intelligence and neuroscience. (shrink)

It is widely agreed that the intelligibility of modal metaphysics has been vindicated. Quine's arguments to the contrary supposedly confused analyticity with metaphysical necessity, and rigid with non-rigid designators.2 But even if modal metaphysics is intelligible, it could be misconceived. It could be that metaphysical necessity is not absolute necessity – the strictest real notion of necessity – and that no proposition of traditional metaphysical interest is necessary in every real sense. If there were nothing otherwise “uniquely metaphysically significant” about (...) metaphysical necessity, then paradigmatic metaphysical necessities would be necessary in one sense of “necessary”, not necessary in another, and that would be it. The question of whether they were necessary simpliciter would be like the question of whether the Parallel Postulate is true simpliciter – understood as a pure mathematical conjecture, rather than as a hypothesis about physical spacetime. In a sense, the latter question has no objective answer. In this article, I argue that paradigmatic questions of modal metaphysics are like the Parallel Postulate question. I then discuss the deflationary ramifications of this argument. I conclude with an alternative conception of the space of possibility. According to this conception, there is no objective boundary between possibility and impossibility. Along the way, I sketch an analogy between modal metaphysics and set theory. (shrink)

The doctrine that whatever could exist does exist leads to a proliferation of possibly concrete objects given certain principles of recombination. If, for example, there could have been a large infinite number of concrete objects, then there is at least the same number of possibly concrete objects in existence. And further cardinality considerations point to a tension between the preceding doctrine and the Cantorian conception of the absolutely infinite. This paper develops a parallel problem for a variety of possible (...) worlds accounts of modality which eschew the commitment to a plethora of possibly concrete objects. Moreover, the difficulty is importantly different from more familiar threats of paradox exemplified by certain descendants of Russell's paradox of propositions and Kaplan's paradox. (shrink)

Higher-order logic augments first-order logic with devices that let us generalize into grammatical positions other than that of a singular term. Some recent metaphysicians have advocated for using these devices to raise and answer questions that bear on many traditional issues in philosophy. In contrast to these 'higher-order metaphysicians', traditional metaphysics has often focused on parallel, but importantly different, questions concerning special sorts of abstract objects: propositions, properties and relations. The answers to the higher-order and the property-theoretic questions (...) may coincide sometimes but will often come apart. I argue that when they do, the higher-order questions are closer to the metaphysical action and so it would be better for these debates to proceed in higher-order terms. (shrink)

According to the plurivaluationist, our vague discourse doesn’t have a single meaning. Instead, it has many meanings, each of which is precise—and it is this plurality of meanings that is the source of vagueness. I believe plurivaluationist positions are underdeveloped and for this reason unpopular. This paper attempts to correct this situation by offering a particular development of plurivaluationism that I call supersententialism. The supersententialist leverages lessons from another area of research—the Problem of the Many—in service of the plurivaluationist position. (...) The Problem reveals theoretical reasons to accept that there are many cats where we thought there was one; the supersententialist claims that we are in a similar situation with respect to languages, propositions and sentences. I argue that the parallel suggested by the supersententialist reveals unappreciated advantages and lines of defense for plurivaluationism. (shrink)

Nihilism, Nietzsche and the Doppelganger Problem Was Nietzsche a nihilist? Yes, because, like J. L. Mackie, he was an error-theorist about morality, including the elitist morality to which he himself subscribed. But he was variously a diagnostician, an opponent and a survivor of certain other kinds of nihilism. Schacht argues that Nietzsche cannot have been an error theorist, since meta-ethical nihilism is inconsistent with the moral commitment that Nietzsche displayed. Schacht’s exegetical argument parallels the substantive argument (advocated in recent years (...) by Wright and Blackburn) that Mackie’s error theory can’t be true because if it were, we would have to give up morality or give up moralizing. I answer this argument with a little bit of help from Nietzsche. I then pose a problem, the Doppelganger Problem, for the meta-ethical nihilism that I attribute to Mackie and Nietzsche. (If A is a moral proposition then not-A is a moral proposition: hence not all moral propositions can be false.) I solve the problem by reformulating the error theory and also deal with a variant of the problem, the Reinforced Doppelganger, glancing at a famous paper of Ronald Dworkin’s. Thus, whatever its demerits, the error theory, is not self-refuting, nor does it require us to give up morality. (shrink)

The aim of this paper is to offer a diagnosis. It focuses on the problem of moral luck, but, unlike most papers on that topic, offers no solution to the problem. Instead, what I do is discuss a number of attempts to show there is no such thing as moral luck, argue that they fail and, more importantly, that we should not be surprised they fail. I then suggest that the difficulty of the problem posed by moral luck is paralleled (...) by another problem about luck, namely the problem of coming up with an account of propositional knowledge that does not count certain lucky guesses as knowledge. The comparison is instructive. It brings home how hard it is to eliminate luck. As such, we should not expect a solution to either problem to be forthcoming. I also note an important disanalogy between the two problems. While we can quite easily accept that luck plays a role in knowledge, the existence of moral luck threatens to cause a good deal more trouble. (shrink)

It is widely agreed that the intelligibility of modal metaphysics has been vindicated. Quine's arguments to the contrary supposedly confused analyticity with metaphysical necessity, and rigid with non-rigid designators.2 But even if modal metaphysics is intelligible, it could be misconceived. It could be that metaphysical necessity is not absolute necessity – the strictest real notion of necessity – and that no proposition of traditional metaphysical interest is necessary in every real sense. If there were nothing otherwise “uniquely metaphysically significant” about (...) metaphysical necessity, then paradigmatic metaphysical necessities would be necessary in one sense of “necessary”, not necessary in another, and that would be it. The question of whether they were necessary simpliciter would be like the question of whether the Parallel Postulate is true simpliciter – understood as a pure mathematical conjecture, rather than as a hypothesis about physical spacetime. In a sense, the latter question has no objective answer. In this article, I argue that paradigmatic questions of modal metaphysics are like the Parallel Postulate question. I then discuss the deflationary ramifications of this argument. I conclude with an alternative conception of the space of possibility. According to this conception, there is no objective boundary between possibility and impossibility. Along the way, I sketch an analogy between modal metaphysics and set theory. (shrink)

Recently there has been a growing literature on the concept of moral certainty. This concept, which is inspired by Wittgenstein’s reflections in On Certainty, is most prominently argued for by Nigel Pleasants. Pleasants contends that there is a meaningful parallel to be drawn between the epistemic certainties discussed by Wittgenstein and moral certainties. These moral certainties are unreflective, non-propositional, and show in the ways that we act. In addition, these certainties cannot be doubted by a reasonable moral agent. In (...) a recently published article, Fairhurst is critical of Pleasants’ account. Fairhurst argues that there are problems with Pleasants’ example of a moral certainty, 'it is wrong to kill innocent non-threatening people'. Fairhurst appeals to euthanasia as an example of when a reasonable person could meaningfully doubt that it is wrong to kill innocent, non-threatening people. If this is a certainty, then a doubt such as this should not be possible. In addition, he argues that Pleasants’ claim that moral certainties are natural is not well substantiated. In this article, I attempt to defend an account of moral certainty against Fairhurst’s criticisms. I divide his criticisms into two parts. His first set of criticisms deal with Pleasants’ example of a moral certainty. I argue that some of his criticisms are inconsistent while others can be addressed by making a small amendment to Pleasants’ account. His second criticism deals with Pleasants’ claim that moral certainties are natural. In order to address this criticism, I appeal to Machery’s Nomological Account of human nature and use it as a basis that allows us to consistently make the claim that there are natural moral certainties. (shrink)

Divided into two parts, the first concentrates on the logical properties of propositions, their relation to facts and sentences, and the parallel objects of commands and questions. The second part examines theories of intentionality and discusses the relationship between different theories of naming and different accounts of belief.

This paper examines an ancient debate over the rationality of perception. What leads the Stoics to affirm, and the Epicureans to deny, that to form a sense-impression is an activity of reason? The answer, we argue, lies in a disagreement over what is required for epistemic success. For the Stoics, epistemic success consists in believing the right propositions, and only rational states, in virtue of their predicational structure, put us in touch with propositions. Since they identify some sense-impressions (...) as criteria of truth and thus as the basis for epistemic success, the Stoics maintain that sense-impressions must be rational. The Epicureans agree with the Stoics that sense-impressions function as criteria of truth, and also agree broadly on what it means for a state to be rational, but deny that sense-impressions are rational because (1) they think that epistemic success must be supported by a state that is necessarily error-free and (2) accept that rational states can be false. In reconstructing this debate, we refine the standard interpretation of the fundamental difference between Epicurean and Stoic epistemology and also develop parallels with epistemological debates today. One upshot is a more nuanced appreciation of the merits of Epicurean epistemology vis-à-vis the Stoics. (shrink)

You reach for the bowl with ‘sugar’ written on it only to discover, from the bad taste of your coffee, that it contained salt. Mundane experiences like these show that epistemic justification does not necessarily hold stable across possible changes of information. One can be justified in believing a proposition at a certain time (that the bowl contains sugar) and cease to be justified at a later time, as one enlarges one’s epistemic perspective (as one drinks a salty coffee). When (...) this happens, one’s justification has been defeated. An epistemic defeater, broadly speaking, is that in terms of which the defeat of justification proceeds. The notion of an epistemic defeater is mostly associated with J. Pollock’s work on reasoning and inference. Pollock has provided the canonical definition of an epistemic defeater and proposed an influential taxonomy in terms of the way different types of defeaters induce their characteristic effects. The notion of an epistemic defeater has acquired a broader meaning in current epistemology, and several distinctions have been introduced that have contributed to a more nuanced understanding of the phenomenon of defeat as well as to complement Pollock’s original taxonomy. The correlated notion of a propositional defeater, defined in terms of would-be defeat of justification, is appealed to by the proponents of the defeasibility theory in the parallel debate about knowledge to explain what prevents a justified true belief from constituting knowledge in Gettier cases. (shrink)

This paper examines three propositions: “First to arise within intellectual awareness is the notion of Being”; the human being is defined as “the rational animal”; and knowing involves “the complete return of the subject into itself.” Its starting point is an examination of what seems trivial: the letter ‘F’ in ‘First.’ It involves eidetic recognition of the alphabet and is identically the same, not only in different times and places and in different type-faces or hand-written form, but in differing (...) media: visual, audile, tactual. And eidetic recognition is also involved in the terms into which the letters or sounds or embossings enter, each of which is definable in terms of other terms which, in turn, are definable in other terms until we see that the whole itself is articulated in terms of the interlacing of meanings. What grounds such recognition is the openness to the whole introduced by the notion of being. The unrestrictedness of the openness is paralleled by the coemergence of the principle of noncontradiction which governs coherent discourse. In both sensory presentation and intellectual apprehension we are outside our spatial inside, with the things manifest in the environment and in terms of the world of public meaning expressed in language. The second part of the paper traces the various options for understanding the notion of being in the history of Western thought: Parmenides, Plato, Aristotle, Aquinas, Scotus, Spinoza, Hegel, Nietzsche, Heidegger, and Derrida. (shrink)

Hume regards the ‘absolute’ necessity attending demonstrable propositions as an expression of the limitations of human imagination. When we register our modal commitments in ordinary descriptive language, affirming that there are such-and-such absolute necessities, possibilities, and impossibilities, we are projecting our sense of what the human mind can and cannot conceive. In some ways the account parallels Hume’s famous treatment of the necessity of causes, and in some respects it anticipates recent expressivist theories of absolute modality. I marshal the (...) evidence for this interpretation, show how it can explain a number of otherwise puzzling features of Hume’s modal epistemology and metaphysics, and situate this account of our modal discourse in Hume’s wider programme for a science of human nature. (shrink)

The contribution deals with knowledge of what to do, and how, where, when and why to do it, as it is found in a multitude of plans, rules, procedures, maxims, and other instructions. It is argued that while this knowledge is conceptual and propositional, it is still irreducible to theoretical knowledge of what is the case and why it is the case. It is knowledge of goals, of ends and means, rather than of facts. It is knowledge-to that is irreducibly (...) practical in having world to mind direction of fit and the essential function of guiding as yet uncompleted action. While practical knowledge is fundamentally different from theoretical knowledge in terms of mind-world relations, the practical and theoretical domains are still parallel in terms of justificatory and inferential relations, they are like mirror images of one another. It is shown that if this view of practical knowledge is accepted, convincing Gettier cases for practical knowledge can be constructed. An extensive analysis of these cases demonstrates the usefulness of the notions of practical deduction, abduction, and induction. (shrink)

Various sexist and racist beliefs ascribe certain negative qualities to people of a given sex or race. Epistemic allies are people who think that in normal circumstances rationality requires the rejection of such sexist and racist beliefs upon learning of many counter-instances, i.e. members of these groups who lack the target negative quality. Accordingly, epistemic allies think that those who give up their sexist or racist beliefs in such circumstances are rationally responding to their evidence, while those who do not (...) are irrational in failing to respond to their evidence by giving up their belief. This is a common view among philosophers and non-philosophers. But epistemic allies face three problems. First, sexist and racist beliefs often involve generic propositions. These sorts of propositions are notoriously resilient in the face of counter-instances since the truth of generic propositions is typically compatible with the existence of many counter-instances. Second, background beliefs can enable one to explain away counter-instances to one’s beliefs. So even when counter-instances might otherwise constitute strong evidence against the truth of the generic, the ability to explain the counter-instances away with relevant background beliefs can make it rational to retain one’s belief in the generic despite the existence of many counter-instances. The final problem is that the kinds of judgements epistemic allies want to make about the irrationality of sexist and racist beliefs upon encountering many counter-instances is at odds with the judgements that we are inclined to make in seemingly parallel cases about the rationality of non-sexist and non-racist generic beliefs. Thus epistemic allies may end up having to give up on plausible normative supervenience principles. All together, these problems pose a significant prima facie challenge to epistemic allies. In what follows I explain how a Bayesian approach to the relation between evidence and belief can neatly untie these knots. The basic story is one of defeat: Bayesianism explains when one is required to become increasingly confident in chance propositions, and confidence in chance propositions can make belief in corresponding generics irrational. (shrink)