This paper discusses two versions of reliabilism: modal and probabilistic reliabilism. Modal reliabilism faces the problem of the missing closeness metric for possible worlds while probalistic reliabilism faces the problem of the relevant reference class. Despite the severity of these problems, reliabilism is still very plausible (also for independent reasons). I propose to stick with reliabilism, propose a contextualist (or, alternatively, harmlessly relativist) solution to the above problems and suggest that probabilistic (...) class='Hi'>reliabilism has the advantage over modal reliabilism. (shrink)

This paper aims to provide a novel response on behalf of Process Reliabilism to the Swamping Problem. Unlike previous responses, the present response does not involve conditional probabilities (as Goldman and Olsson do), it does not appeal to permissivism or attitudes towards epistemic risk (as Pettigrew does), it will not depend on the generality of the problem (as Carter and Jarvis do) and it does not embrace either evidentialism or evidence monism (as Bjelde does). Instead it appeals to the (...) modal properties of those beliefs formed through reliable process-types. What is more, the argument is generalizable: while I will frame my conclusion in Process Reliabilist terms, it should be of interest to anyone who is a truth monist regarding epistemic value. (shrink)

Discrimination is a central epistemic capacity but typically, theories of discrimination only use discrimination as a vehicle for analyzing knowledge. This paper aims at developing a self-contained theory of discrimination. Internalist theories of discrimination fail since there is no compelling correlation between discriminatory capacities and experiences. Moreover, statistical reliabilist theories are also flawed. Only a modal theory of discrimination is promising. Versions of sensitivity and adherence that take particular alternatives into account provide necessary and sufficient conditions on discrimination. Safety (...) in contrast is not sufficient for discrimination as there are cases of safety that are clearly instances of discrimination failure. The developed account of discrimination between objects will be extended to discrimination between kinds and between types. (shrink)

El propósito de este artículo es cuestionar la lectura tradicional de las Meditaciones metafísicas, una lectura que, abstrayendo del reto escépticode una reducción de la razón al absurdo al que se enfrenta Descartes,magnifica la prioridad epistémica del argumento del Cogito, y que, haciendocaso omiso de su estrategia anti-escéptica, es incapaz de apreciar que, másque la recopilación de mejores evidencias a favor de las proposicionesnucleares, su función es la de sustraer razones para dudar, de tal forma queel Investigador adquiera una posición (...) ilustrada desde la que los escenariosescépticos carezcan de sentido. Descartes propone una versión modal ometafísica de confiabilismo análoga a la defendida en el panoramacontemporáneo por Ernest Sosa, una posición capaz de superar sincircularidad el escepticismo y que muestra cómo el uso correcto de la razón desemboca en una teoría ontológica que elimina la posibilidad de quenuestras facultades cognitivas no sean fiables. (shrink)

How to accommodate the possibility of lucky true beliefs in necessary (or armchair) truths within contemporary modal epistemology? According to safety accounts luck consists in the modal proximity of a false belief, but a belief in a true mathematical proposition could not easily be false because a proposition believed could never be false. According to Miščević modal stability of a true belief under small changes in the world is not enough, stability under small changes in the cognizer (...) should also (and primarily) be considered. I argue for a more traditional modal reliabilism based on the critical question: how easy is it for a belief to be false, given the way it was formed? A belief (a priori or a posteriori) is then agent-lucky when based on a specific method which might easily lead to a false belief in the target proposition. Miščević suggests a unifying approach in terms of virtue epistemology. It seems to me that this approach, if successful, will undermine the project that he started with: formulate an anti-luck condition in the frame of a modal theory of luck. (shrink)

The topic of a priori knowledge is approached through the theory of evidence. A shortcoming in traditional formulations of moderate rationalism and moderate empiricism is that they fail to explain why rational intuition and phenomenal experience count as basic sources of evidence. This explanatory gap is filled by modal reliabilism -- the theory that there is a qualified modal tie between basic sources of evidence and the truth. This tie to the truth is then explained by the (...) theory of concept possession: this tie is a consequence of what, by definition, it is to possess (i.e., to understand) one’s concepts. A corollary of the overall account is that the a priori disciplines (logic, mathematics, philosophy) can be largely autonomous from the empirical sciences. (shrink)

This paper provides a defense of two traditional theses: the Autonomy of Philosophy and the Authority of Philosophy. The first step is a defense of the evidential status of intuitions (intellectual seemings). Rival views (such as radical empiricism), which reject the evidential status of intuitions, are shown to be epistemically self-defeating. It is then argued that the only way to explain the evidential status of intuitions is to invoke modal reliabilism. This theory requires that intuitions have a certain (...) qualified modal tie to the truth. This result is then used as the basis of the defense of the Autonomy and Authority theses. The paper closes with a defense of the two theses against a potential threat from scientific essentialism. (shrink)

Scientific essentialism is the view that some necessities can be known only with the aid of empirical science. The thesis of the paper is that scientific essentialism does not extend to the central questions of philosophy and that these questions can be answered a priori. The argument is that the evidence required for the defense of scientific essentialism is reliable only if the intuitions required by philosophy to answer its central questions is also reliable. Included is an outline of a (...) modal reliabilist theory of basic evidence and a concept-possession account of the reliability of a priori intuition. (shrink)

The paper elaborates upon various points and arguments in the author’s “A Priori Knowledge and the Scope of Philosophy” (Philosophical Studies, 1993), in which the author defends the autonomy of philosophy from the empirical sciences. It provides, for example, an extended defense of the modal reliabilist theory of basic evidence, including a new argument against evolutionary explanations of the reliability of intuitions. It also contains a fuller discussion of how to neutralize the threat of scientific essentialism to the autonomy (...) of philosophy. (shrink)

The topic of a priori knowledge is approached through the theory of evidence. A shortcoming in traditional formulations of moderate rationalism and moderate empiricism is that they fail to explain why rational intuition and phenomenal experience count as basic sources of evidence. This explanatory gap is filled by modal reliabilism -- the theory that there is a qualified modal tie between basic sources of evidence and the truth. This tie to the truth is then explained by the (...) theory of concept possession: this tie is a consequence of what, by definition, it is to possess (i.e., to understand) one’s concepts. A corollary of the overall account is that the a priori disciplines (logic, mathematics, philosophy) can be largely autonomous from the empirical sciences. (shrink)

This paper contains replies to comments on the author's paper "A Priori Knowledge and the Scope of Philosophy." Several points in the argument of that paper are given further clarification: the notion of our standard justificatory procedure, the notion of a basic source of evidence, and the doctrine of modal reliabilism. The reliability of intuition is then defended against Lycan's skepticism and a response is given to Lycan's claim that the scope of a priori knowledge does not include (...) philosophically central topics such as the nature of consciousness. Next a counterfactual account of intuitions proposed by Sosa is criticized. Finally, in response to certain questions raised by Sosa, the explanation of the evidential status of intuition offered in the original paper receives further elaboration. (shrink)

This paper is a condensed version of the author’s “A Theory of the A Priori” (Pacific Philosophical Quarterly, 2000) for the evidential status of intuitions, the incoherence of radical empiricism. the thesis of modal reliabilism, and the Autonomy of Philosophy Thesis (according to which the a priori disciplines are autonomous from empirical science).

Reliabilism is the dominant theory in contemporary analytic epistemology. This chapter reviews some considerations which throw doubt on the widely accepted thesis or R‐NEC that reliability is necessary for knowledge. It considers whether the generally pessimistic results in the experimental literature from social psychology concerning subjects’ ability in a test situation to tell, from behavioral cues, whether a speaker is lying, present a severe challenge for R‐NEC. The chapter develops a more classic line of thought invoking intuitions about cases (...) which suggests that there is, however, cause from another source to put in question R‐NEC, at least in the case of testimonial knowledge. It elucidates some threads from what has emerged so far, to show how testimony reveals the need for a new kind of analysis, illustrating the need and scope for social epistemology. The chapter proposes Approved‐List Reliabilism as a new general theory of knowledge which incorporates reliabilist intuitions, but at a different point. (shrink)

The Meno problem, asking for the surplus value of knowledge beyond the value of true justified belief, was recently much treated within reliabilist and virtue epistemologies. The answers from formal epistemology, by contrast, are quite poor. This paper attempts to improve the score of formal epistemology by precisely explicating Timothy Williamson's suggestion that ‘present knowledge is less vulnerable than mere present true belief to rational undermining by future evidence’. It does so by combining Nozick's sensitivity analysis of knowledge with Spohn's (...) fact‐asserting epistemic interpretation of conditionals. Accordingly, the surplus value of knowledge lies in a specific kind of stability of knowledge, which differs, though, from that claimed by other so‐called stability analyses of knowledge. (shrink)

This introductory chapter presents an overview of the different topics discussed in the subsequent chapters. These include process reliabilism, evidentialism, viral epistemology, anti-luminosity argument, and modal epistemology.

Philosophers commonly define knowledge as justified true beliefs. A heated debate exists, however, about what makes a belief justified. In this article, we examine the question of belief justification from a psychological perspective, focusing on the subjective confidence in a belief that the person has just formed. Participants decided whether to accept or reject a proposition depicting a social belief, and indicated their confidence in their choice. The task was repeated six times, and choice latency was measured. The results were (...) analyzed within a Self-Consistency Model of subjective confidence. According to SCM, the decision to accept or reject a proposition is based on the on-line sampling of representations from a pool of representations associated with the proposition. Respondents behave like intuitive statisticians who infer the central tendency of a population based on a small sample. Confidence depends on the consistency with which the belief was supported across the sampled representations, and reflects the likelihood that a new sample will yield the same decision. The results supported the assumption of a commonly shared population of representations associated with each proposition. Based on this assumption, analyses of within-person consistency and cross-person consensus provided support for the model. As expected, choices that deviated from the person’s own modal judgment or from the consensually held judgment took relatively longer to form and were associated with relatively lower confidence, presumably because they were based on non-representative samples. The results were discussed in relation to major epistemological theories – foundationalism, coherentism and reliabilism. (shrink)

My paper challenges the externalist mainstream assumptions towards the understanding of religious beliefs (i.e., reliabilism by W.Alston, the warrant belief approach by A.Plantinga, the neowittgensteinian analysis of doxastic systems). According to such assumptions, religious beliefs should be evaluated rational in terms of the same doxastic standard giving justification for ordinary factual beliefs. Moving from the empiricist intuition that the kind of content of belief matters to the form of belief and the justification practices for it, I argue for the (...) claim that religious beliefs do not concern facts or experiences but assiological interpretations of facts or experiences. After some brief introductory considerations, in the second section of my paper I provide criteria for distinguishing between factual and non factual beliefs, and I offer a general account for the doxastic spectrum. In the subsequent section I characterize the assumption of religious beliefs as qualitative, mostly implicit and in the de dicto modality. In order to prove my characterization I draw a phenomenology of religious belief from individual testimonies concerning religious conversion. I finally conclude answering some objections in the fourth section of the paper. (shrink)

This book contains essays published originally in the last three decades and one paper that appears in print for the first time. They deal with metaphysical, epistemological, and semantical problems concerning knowledge, mind, and reality. The book is mainly focused on “the various kinds of dependencies that might hold between mind and reality” and substantially unified by “consistent commitment to realism”. The essays are arranged thematically into three groups. The first concerns the notion of knowledge in general, the nature of (...) a priori knowledge, and of modality. McGinn favors a version of the reliabilist account of knowledge, for which a belief counts as knowledge if it has been produced by a method leading to true beliefs in a significant number of relevant cases. He proposes to define a priori knowledge as noncausal knowledge and defends a radically nonreductive conception of modality as a mode of property instantiation. The second part contains essays relevant to the theory of mental content, including “The Structure of Content” which, as McGinn suggests, is probably the most widely cited paper he has published. It also includes, among others, a less widely known, but very interesting paper on reference, proposing a plausible alternative to both descriptive and causal theories of reference. The third part contains essays that mainly try to undermine Dummettian semantic antirealism, and argue for realism, irrespective of its epistemological costs. It concludes with two recent essays on color: one defends supervenience of color properties upon dispositional properties of objects, and the other explores consequences of the neutrality of color experience with respect to the ontological nature of color. (shrink)

According to accessibilism, there is an accessibility condition on justification. More specifically, accessibilism claims that facts about justification are a priori accessible, where a priori is used in the traditional sense that a condition is a priori just in case it doesn't depend on any of the sense modalities. The most prominent argument for accessibilism draws on BonJour and Lehrer's unfamiliar faculty scenarios. Recently, however, several objections have been raised against it. In this article, I defend the argument against three (...) prominent objections from the recent literature. (shrink)

I review recent work from armchair and cross-cultural epistemology on whether humans possess a knowledge concept as part of a universal “folk epistemology.” The work from armchair epistemology fails because it mischaracterizes ordinary knowledge judgments. The work from cross-cultural epistemology provides some defeasible evidence for a universal folk epistemology. I argue that recent findings from comparative psychology establish that humans possess a species-typical knowledge concept. More specifically, recent work shows that knowledge attributions are a central part of primate social cognition, (...) used to predict others’ behavior and guide decision-making. The core primate knowledge concept is that of truth detection (across different sensory modalities) and retention (through memory) and may also include rudimentary forms of indirect truth discovery through inference. In virtue of their evolutionary heritage, humans inherited the primate social-cognitive system and thus share this core knowledge concept. (shrink)

Kelly Becker has argued that in an externalist anti-luck epistemology, we must hold that knowledge requires the satisfaction of both a modalized tracking condition and a process reliability condition. We raise various problems for the examples that are supposed to establish this claim.

This volume presents a selection of essays by the leading philosopher Christopher S. Hill. Together, they address central philosophical issues related to four key concerns: the nature of truth; the relation between experiences and brain states; the relation between experiences and representational states; and problems concerning knowledge.

The purpose of this study is to propose new similarity measures namely rough variational coefficient similarity measure under the rough neutrosophic environment. The weighted rough variational coefficient similarity measure has been also defined. The weighted rough variational coefficient similarity measures between the rough ideal alternative and each alternative are xxxxx calculated to find the best alternative. The ranking order of all the alternatives can be determined by using the numerical values of similarity measures. Finally, an illustrative example has been provided (...) to show the effectiveness and validity of the proposed approach. Comparisons of decision results of existing rough similarity measures have been provided. (shrink)

This paper is devoted to present Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method for multi-attribute group decision making under rough neutrosophic environment. The concept of rough neutrosophic set is a powerful mathematical tool to deal with uncertainty, indeterminacy and inconsistency. In this paper, a new approach for multi-attribute group decision making problems is proposed by extending the TOPSIS method under rough neutrosophic environment. Rough neutrosophic set is characterized by the upper and lower approximation operators and the (...) pair of neutrosophic sets that are characterized by truth-membership degree, indeterminacy membership degree, and falsity membership degree. In the decision situation, ratings of alternatives with respect to each attribute are characterized by rough neutrosophic sets that reflect the decision makers’ opinion. Rough neutrosophic weighted averaging operator has been used to aggregate the individual decision maker’s opinion into group opinion for rating the importance of attributes and alternatives. Finally, a numerical example has been provided to demonstrate the applicability and effectiveness of the proposed approach. (shrink)

Timothy Williamson gives an original and provocative treatment of deep metaphysical questions about existence, contingency, and change, using the latest resources of quantified modal logic. Contrary to the widespread assumption that logic and metaphysics are disjoint, he argues that modal logic provides a structural core for metaphysics.

This essay defends a novel form of virtue epistemology: Modal Virtue Epistemology. It borrows from traditional virtue epistemology the idea that knowledge is a type of skillful performance. But it goes on to understand skillfulness in purely modal terms — that is, in terms of success across a range of counterfactual scenarios. We argue that this approach offers a promising way of synthesizing virtue epistemology with a modal account of knowledge, according to which knowledge is safe belief. (...) In particular, we argue that the modal elements of the view offer important advantages over traditional virtue epistemology, which assigns a central explanatory role to aptness. At the same time, the virtue epistemological elements of the theory reveal new avenues for overcoming obstacles to traditional modal accounts of knowledge. Finally, we highlight the advantages of Modal Virtue Epistemology over alternative syntheses, such as Pritchard's (2012) hybrid approach. (shrink)

This book is intended to serve as an advanced text and reference work on modal logic, a subject of growing importance which has applications to philosophy and linguistics. Although it is based mainly on research which I carried out during the years 1969-1973, it also includes some related results obtained by other workers in the field. Parts 0, 1 and 2, can be used as the basis of a one year graduate course in modal logic. The material which (...) they contain has been taught in such courses at Stanford since 1970. The remaining parts of the book contain more than enough material for a second course in modal logic. The exercises supplement the text and are usually difficult. I wish to thank Stanford University and Bar-Han University for making it possible for me to continue and finish this work, and A. Ungar for correcting the typescript. Bar-Ilan University, Israel Dov M. GABBA Y PART 0 AN INTRODUCTION TO GENERAL INTENSIONAL LOGICS CHAPTER 0 CONSEQUENCE RELATIONS Motivation We introduce the notions of a consequence relation and of a semantics. We show that every consequence relation is complete for a canonical semantics. We define the notion of one semantics being Dian in another and study the basic properties of this notion. The concepts of this chapter are generalizations of the various notions of logical system and possible world semantics found in the literature. (shrink)

This essay offers a rearticulation and defence of the modal account of luck that the author developed in earlier work . In particular, the proposal is situated within a certain methodology, a component of which is paying due attention to the cognitive science literature on luck ascriptions. It is shown that with the modal account of luck properly articulated it can adequately deal with some of the problems that have recently been offered against it, and that the view (...) has a number of attractions over competing proposals, such as the lack of control account. (shrink)

Three popular views regarding the modal status of the laws of nature are discussed: Humean Supervenience, nomic necessitation, and scientific/dispositional essentialism. These views are examined especially with regard to their take on the apparent modal force of laws and their ability to explain that modal force. It will be suggested that none of the three views, at least in their strongest form, can be maintained if some laws are metaphysically necessary, but others are metaphysically contingent. Some reasons (...) for thinking that such variation in the modal status of laws exists will be presented with reference to physics. This drives us towards a fourth, hybrid view, according to which there are both necessary and contingent laws. The prospects for such a view are studied. (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)

My goal in this paper is to show that Kant’s prohibition on certain kinds of knowledge of things-in-themselves is motivated less by his anti-soporific encounter with Hume than by his new view of the distinction between “real” and “logical” modality, a view that developed out of his reflection on the rationalist tradition in which he was trained. In brief: at some point in the 1770’s, Kant came to hold that a necessary condition on knowing a proposition is that one be (...) able to prove that all the items it refers to are either really possible or really impossible. Most propositions about things-in-themselves, in turns out, cannot meet this condition. I conclude by suggesting that the best interpretation of this modal condition is as a kind of coherentist constraint. (shrink)

What precisely are fragments of classical first-order logic showing “modal” behaviour? Perhaps the most influential answer is that of Gabbay 1981, which identifies them with so-called “finite-variable fragments”, using only some fixed finite number of variables (free or bound). This view-point has been endorsed by many authors (cf. van Benthem 1991). We will investigate these fragments, and find that, illuminating and interesting though they are, they lack the required nice behaviour in our sense. (Several new negative results support this (...) claim.) As a counterproposal, then, we define a large fragment of predicate logic characterized by its use of only bounded quantification. This so-called guarded fragment enjoys the above nice properties, including decidability, through an effectively bounded finite model property. (These are new results, obtained by generalizing notions and techniques from modal logic.) Moreover, its own internal finite variable hierarchy turns out to work well. Finally, we shall make another move. The above analogy works both ways. Modal operators are like quantifiers, but quantifiers are also like modal operators. This observation inspires a generalized semantics for first-order predicate logic with accessibility constraints on available assignments (cf. N´emeti 1986, 1992) which moves the earlier quantifier restrictions into the semantics. This provides a fresh look at the landscape of possible predicate logics, including candidates sharing various desirable features with basic modal logic – in particular, its decidability. (shrink)

This text aims to convey some of the interest and charm of modal logic, and to put a reader new to the subject in a position to have an informed opinion as to its applicability to each of several areas of philosophical concern in which the merits of a modal approach' have been controversial. he main focus, for these purposes, is on normal modal logics, though some attention is given to the non-normal side of the picture.

This book on modal logic is especially designed for philosophy students. It provides an accessible yet technically sound treatment of modal logic and its philosophical applications. Every effort is made to simplify the presentation by using diagrams instead of more complex mathematical apparatus. These and other innovations provide philosophers with easy access to a rich variety of topics in modal logic, including a full coverage of quantified modal logic, non-rigid designators, definite descriptions, and the de-re de-dicto (...) distinction. Discussion of philosophical issues concerning the development of modal logic is woven into the text. The book uses natural deduction systems, which are widely regarded as the easiest to teach and use. It also includes a diagram technique that extends the method of truth trees to modal logic. This provides a foundation for a novel method for showing completeness that is easy to extend to quantifiers. This second edition contains a new chapter on logics of conditionals, an updated and expanded bibliography, and is updated throughout. (shrink)

In this paper, I formulate, elucidate, and defend a version of modal realism with overlap, the view that objects are literally present at more than one possible world. The version that I defend has several interesting features: (i) it is committed to an ontological distinction between regions of spacetime and material objects; (ii) it is committed to compositional pluralism, which is the doctrine that there is more than one fundamental part-whole relation; and (iii) it is the modal analogue (...) of endurantism, which is the doctrine that objects persist through time by being wholly present at each moment they are located. (shrink)

In this chapter, it is suggested that our epistemic access to metaphysical modality generally involves rationalist, a priori elements. However, these a priori elements are much more subtle than ‘traditional’ modal rationalism assumes. In fact, some might even question the ‘apriority’ of these elements, but I should stress that I consider a priori and a posteriori elements especially in our modal inquiry to be so deeply intertwined that it is not easy to tell them apart. Supposed metaphysically necessary (...) identity statements involving natural kind terms are a good example: the fact that empirical input is crucial in establishing their necessity has clouded the role and content of the a priori input, as I have previously argued. For instance, the supposed metaphysically necessary identity statement involving water and its microstructure can only be established with the help of a controversial a priori principle concerning the determination of chemical properties by microstructure. The Kripke-Putnam framework of modal epistemology fails precisely because it is unclear whether the required a priori element is present. My positive proposal builds on E. J. Lowe’s work. Lowe holds that our knowledge of metaphysical modality is based on our knowledge of essence. Lowe’s account strives to offer a uniform picture of modal epistemology: essence is the basis of all our modal knowledge. This is the basis of Lowe’s modal rationalism. I believe that Lowe’s proposal is on the right lines in the case of abstract objects, but I doubt that it can be successfully applied to the case of natural kinds. Accordingly, the case of natural kinds will be my main focus and I will suggest that modal rationalism, at least as it is traditionally understood, falls short of explaining modal knowledge concerning natural kinds. Yet, I think that Lowe has identified something of crucial importance for modal epistemology, namely the essentialist, a priori elements present in our modal inquiry. The upshot is that rather than moving all the way from modal rationalism to modal empiricism, a type of hybrid approach, ‘empirically-informed modal rationalism ’, can be developed. (shrink)

Shelly Kagan argues in his ‘What's Wrong with Speciesism?’ for four provocative claims: 1. speciesism is not necessarily a mere prejudice; 2. most people are not speciesists; 3. ‘modal personism’ more closely reflects what most people believe, and 4. modal personism might be true. In this article, I object to Kagan's account of what constitutes a ‘mere prejudice’, and I object to the sort of argument he uses to show that most people are not speciesist. I then attempt (...) to motivate, and defend what I take to be the best version of modal personism; answer several problems for the view; and raise other problems that I think are harder to answer. (shrink)

How, if at all, can scientific progress improve our view of the modal facts? According to rationalist approaches to modal epistemology, science has no substantive role: a priori reflection reveals the structure of modal space, and a posteriori science merely locates us within that modal space, by identifying the actual properties and structures instantiated at our world. According to modal naturalist approaches, science provides evidence about the structure of the underlying modal space. In this (...) paper I distinguish four versions of modal naturalism, with science playing an increasingly robust evidential role, and discuss their plausibility. (shrink)

In this paper we investigate Boolean connexive logics in a language with modal operators: □, ◊. In such logics, negation, conjunction, and disjunction behave in a classical, Boolean way. Only implication is non-classical. We construct these logics by mixing relating semantics with possible worlds. This way, we obtain connexive counterparts of basic normal modal logics. However, most of their traditional axioms formulated in terms of modalities and implication do not hold anymore without additional constraints, since our implication is (...) weaker than the material one. In the final section, we present a tableau approach to the discussed modal logics. (shrink)

Designed for use by philosophy students, this 2006 book provides an accessible, yet technically sound treatment of modal logic and its philosophical applications. Every effort has been made to simplify the presentation by using diagrams in place of more complex mathematical apparatus. These and other innovations provide philosophers with easy access to a rich variety of topics in modal logic, including a full coverage of quantified modal logic, non-rigid designators, definite descriptions, and the de-re de-dictio distinction. Discussion (...) of philosophical issues concerning the development of modal logic is woven into the text. The book uses natural deduction systems and also includes a diagram technique that extends the method of truth trees to modal logic. This feature provides a foundation for a novel method for showing completeness, one that is easy to extend to systems that include quantifiers. (shrink)

Some results on the upper end of the lattice of all modal propositional logics.