This volume provides analyses of the logic-reality relationship from different approaches and perspectives. The point of convergence lies in the exploration of the connections between reality – social, natural or ideal – and logical structures employed in describing or discovering it. Moreover, the book connects logical theory with more concrete issues of rationality, normativity and understanding, thus pointing to a wide range of potential applications. -/- -/- The papers collected in this volume address cutting-edge topics in contemporary discussions amongst specialists. (...) Some essays focus on the role of indispensability considerations in the justification of logical competence, and the wide range of challenges within the philosophy of mathematics. Others present advances in dynamic logical analysis such as extension of game semantics to non-logical part of vocabulary and development of models of contractive speech act. -/- Table of Contents: Introduction: Majda Trobok, Nenad Miščević and Berislav Žarnić.- I. Logical and Mathematical Structures.- Life on the Ship of Neurath: Mathematics in the Philosophy of Mathematics: Stewart Shapiro.- Applied Mathemathics in the Sciences: Dale Jacquette.- The Philosophical Impact of the Löwenheim-Skolem Theorem: Miloš Arsenijević.- Debating (Neo)logicism: Frege and the neo-Fregeans: Majda Trobok.- II. Epistemology and Logic.- Informal Logic and Informal Consequence: Danilo Šuster.- Logical Consequence and Rationality: Nenad Smokrović.- Logic, Indispensability and Aposteriority: Nenad Miščević.- III . Dynamic Logical Models of Meaning.- Extended Game-Theoretical Semantics: Manuel Rebuschi.- Dynamic Logic of Propositional Commitments: Tomoyuki Yamada.- Is Unsaying Polite?: Berislav Žarnić.- IV Logical Methods in Ontological and Linguistic Analyses.- Towards a Formal Account of Identity Criteria: Massimiliano Carrara and Silvia Gaio.- A Mereology for the Change of Parts: Pierdaniele Giaretta and Giuseppe Spolaore.- Russell versus Frege: Imre Rusza.- Goodman’s OnlyWorld: Vladan Djordjević.-. (shrink)

The aim of this note is to discuss the general form and role of identity criteria. We have taken two readings into consideration which express two different functions of identity criteria. The first expresses the epistemic function whilst the second deals with the ontological function. We argue that there are several problems related to the specification of both these functions. As a consequence, we conclude that identity criteria are not necessary to provide ontological legitimacy.

This paper investigates the question of how we manage to single out the natural number structure as the intended interpretation of our arithmetical language. Horsten submits that the reference of our arithmetical vocabulary is determined by our knowledge of some principles of arithmetic on the one hand, and by our computational abilities on the other. We argue against such a view and we submit an alternative answer. We single out the structure of natural numbers through our intuition of the absolute (...) notion of finiteness. (shrink)

Sometimes mereologists have problems with counting. We often don't want to count the parts of maximally connected objects as full‐fledged objects themselves, and we don't want to count discontinuous objects as parts of further, full‐fledged objects. But whatever one takes “full‐fledged object” to mean, the axioms and theorems of classical, extensional mereology commit us to the existence both of parts and of wholes – all on a par, included in the domain of quantification – and this makes mereology look counterintuitive (...) to various philosophers.In recent years, a proposal has been advanced to solve the tension between mereology and familiar ways of counting objects, under the label of Minimalist View. The Minimalist View may be summarized in the slogan: “Count x as an object iff it does not overlap with any y you have already counted as an object”. The motto seems prima facie very promising but, we shall argue, when one looks at it more closely, it is not. On the contrary, the Minimalist View involves an ambiguity that can be solved in quite different directions. We argue that one resolution of the ambiguity makes it incompatible with mereology. This way, the Minimalist View can lend no support to mereology at all.We suggest that the Minimalist View can become compatible with mereology once its ambiguity is solved by interpreting it in what we call an epistemic or conceptual fashion: whereas mereology has full metaphysical import, the Minimalist View may account for our ways of selecting “conceptually salient” entities. But even once it is so disambiguated, it is doubtful that the Minimalist View can help to make mereology more palatable, for it cannot make it any more compatible with commonsensical ways of counting objects. (shrink)

In To be is to be the object of a possible act of choice the authors defended Boolos’ thesis that plural quantification is part of logic. To this purpose, plural quantification was explained in terms of plural reference, and a semantics of plural acts of choice, performed by an ideal team of agents, was introduced. In this paper, following that approach, we develop a theory of concepts that—in a sense to be explained—can be labeled as a theory of logical concepts. (...) Within this theory, we propose a new logicist approach to natural numbers. Then, we compare our logicism with Frege’s traditional logicism. (shrink)

Commonsense ontology often conflicts with the ontology of our best scientific and philosophical theories. However, commonsense ontology, and commonsense belief systems in general, seems to be remarkably efficient and cognitively fundamental. In cases of contrast, it is better to find a way to reconcile commonsense and ”theoretical” ontologies. Given that commonsense ontologies are typically expressed within natural language, a classical procedure of reconciliation is semantical. The strategy is that of individuating the ”ontologically problematic” expressions of natural language and paraphrasing the (...) sentences in which they appear in a (formal) language whose commitments are compatible with those of our best theories. We believe that this strategy of reconciliation, though quite standard, especially in the philosophical literature, is problematic: for a start, it forces us to conclude that the ”real content” of our commonsense expressions and beliefs is different from what it appears. Commonsense ontology becomes just an illusion. We will thus propose an alternative approach: according to our view, a commonsense ontology is reconciled with a theoretical ontology in case it is shown that the explanation of why we believe in the existence of a problematic entity is compatible with our best theories. We will call this kind of reconciliation ”epistemic”. The advantage of an epistemic reconciliation is that commonsense ontology is treated in its own right and could be taken prima facie. Another advantage of the view is that epistemic reconciliation can be analysed through the notion of explaining away: a commonsense ontology is epistemically reconciled with a theoretical ontology if and only if the problematic entities of the commonsense ontology are explained away by ”respectable” entities of the theoretical ontology. In the final part of the paper, we sketch a formal analysis of explaining away. (shrink)

According to the so-called strong variant of Composition as Identity (CAI), the Principle of Indiscernibility of Identicals can be extended to composition, by resorting to broadly Fregean relativizations of cardinality ascriptions. In this paper we analyze various ways in which this relativization could be achieved. According to one broad variety of relativization, cardinality ascriptions are about objects, while concepts occupy an additional argument place. It should be possible to paraphrase the cardinality ascriptions in plural logic and, as a consequence, relative (...) counting requires the relativization either of quantifiers, or of identity, or of the is one of relation. However, some of these relativizations do not deliver the expected results, and others rely on problematic assumptions. In another broad variety of relativization, cardinality ascriptions are about concepts or sets. The most promising development of this approach is prima facie connected with a violation of the so-called Coreferentiality Constraint, according to which an identity statement is true only if its terms have the same referent. Moreover - even provided that the problem with coreferentiality can be fixed - the resulting analysis of cardinality ascriptions meets several difficulties. (shrink)

A minimal constraint on normative reasons seems to be that if some fact is a reason for an agent to φ (act, believe, or feel), the agent could come to know that fact. This constraint is threatened by a well-known type of counterexamples. Self-effacing reasons are facts that intuitively constitute reasons for an agent to φ, but that if they were to become known, they would cease to be reasons for that agent. The challenge posed by self-effacing reasons bears important (...) structural similarities with a range of epistemic paradoxes, most notably the Knowability Paradox. In this article, we investigate the similarities and differences between the two arguments. Moreover, we assess whether some of the approaches to the Knowability Paradox could help solve the challenge posed by self-effacing reasons. We argue that at least two popular approaches to the paradox can be turned into promising strategies for addressing the self-effacing reasons problem. (shrink)

In this short paper we consider Linnebo's thin/thick dichotomy: first, we show that it does not overlap with the very common one between abstract/concrete objects; second, on the basis of some difficulties with the distinction, we propose, as a possible way out, to move from thin/thick objects to thin/thick concepts.

The aim of this paper is to discuss Hughes’ formulation of three‐dimensionalism. Firstly, I observe that the linguistic data do not clearly support his formulation. Secondly, the arguments he uses to state his formulation could be disputed either on the basis of a difference between ordinary language and regimented language, or on the basis of a different notion of temporal part.

The aim of this paper is to discuss Hughes’ formulation of three‐dimensionalism. Firstly, I observe that the linguistic data do not clearly support his formulation. Secondly, the arguments he uses to state his formulation could be disputed either on the basis of a difference between ordinary language and regimented language, or on the basis of a different notion of temporal part.

The goal of the paper is to analyse some specific features of a very central concept for top-level ontologies for information systems: i.e. the concept of artefact. Specifically, we analyse the relation to be a copy of that is strongly linked to the notion of artefact and—as we will demonstrate—could be useful to distinguish artefacts from objects of other kinds. Firstly, we outline some intuitive and commonsensical reasons for the need of a clarification of the notion of artefact in ontologies (...) for information systems, and we analyse some characterisations of the notion given by two top-level ontologies (Cyc and Wordnet). Secondly, we introduce and critically analyse Tzouvaras’ notion of copy. Thirdly, we try to complete an analysis of copy by distinguishing three kinds of copies: replicas (Tzouvaras’ notion of copy), rigid copies, and functional copies. With the help of these three notions we outline a first and preliminary distinction between artefacts, objects of art and natural objects. (shrink)

This is an excerpt from the contentIn the introduction to part I of the symposium we stated that a rational agent could be thought of as an agent who has good reasons for its actions. In formal analyses of economic, medical, political, military and forensic decisions rationality, that is the “goodness” of those reasons, is inextricably intertwined with probability. Typically, those analyses concern decisions in a particular class of uncertain situations, namely “risky” situations, where all the relevant available alternative actions (...) are known, each or most actions are non-deterministic , and the probability of each outcome is known to some degree of approximation. As yet, formal analyses have only begun to scratch the surface of the subtleties implicated in uncertain, but not risky, situations, where the available courses of actions, and/or their possible outcomes, and/or the probabilities of those outcomes, are not all. (shrink)

The moving spotlight account (MS) is a view that combines an eternalist ontology and an A-theoretic metaphysics. The intuition underlying MS is that the present time is somehow privileged and experientially vivid, as if it were illuminated by a moving spotlight. According to MS-theorists, a key reason to prefer MS to B-theoretic eternalism is that our experience of time supports it. We argue that this is false. To this end, we formulate a new family of positions in the philosophy of (...) time, which differ from MS in that, intuitively, they admit a plurality of moving spotlights. We argue that these ‘deviant’ variants of MS cannot be dismissed as conceptually incoherent, and that they are as well-supported by our experience as is MS. One of these variants, however, is consistent with the B-theory. Thus, if our experience of time supports MS, then it supports the B-theory as well. (shrink)

Open futurism is the indeterministic position according to which the future is ‘open’, i.e., there is now no fact of the matter as to what future contingent events will actually obtain. Many open futurists hold a branching conception of time, in which a variety of possible futures exist. This paper introduces two challenges to branching-time open futurism, which are similar in spirit to a challenge posed by Fine to tense realism. The paper argues that, to address the new challenges, open (...) futurists must adopt an objective, non-perspectival notion of actuality and subscribe to an A-theoretic, dynamic conception of reality. Moreover, given a natural understanding of “actual future”, it is perfectly sensible for open futurists to hold that a unique, objectively actual future exists, contrary to a common assumption in the current debate. The paper also contends that recognising the existence of a unique actual future helps open futurists to avoid potential misconceptions. (shrink)

This paper explores taste fragmentalism, a novel approach to matters of taste and faultless disagreement. The view is inspired by Kit Fine’s fragmentalism about time, according to which the temporal dimension can be constituted—in an absolute manner—by states that are pairwise incompatible, provided that they do not obtain together. In the present paper, we will apply this metaphysical framework to taste states. In our proposal, two incompatible taste states (such as the state of rhubarb’s being tasty and the state of (...) rhubarb’s being distasteful) can both constitute reality in an absolute manner, although no agent can have joint access to both states. We will then develop a formalised version of our view by means of an exact truthmaker semantics for taste assertions. Within this framework—we argue—our linguistic and inferential practices concerning cases of faultless disagreement are elegantly vindicated, thus suggesting that taste fragmentalism is worth of further consideration. (shrink)

This special issue collects together nine new essays on logical consequence :the relation obtaining between the premises and the conclusion of a logically valid argument. The present paper is a partial, and opinionated,introduction to the contemporary debate on the topic. We focus on two influential accounts of consequence, the model-theoretic and the proof-theoretic, and on the seeming platitude that valid arguments necessarilypreserve truth. We briefly discuss the main objections these accounts face, as well as Hartry Field’s contention that such objections (...) show consequenceto be a primitive, indefinable notion, and that we must reject the claim that valid arguments necessarily preserve truth. We suggest that the accountsin question have the resources to meet the objections standardly thought to herald their demise and make two main claims: (i) that consequence, as opposed to logical consequence, is the epistemologically significant relation philosophers should be mainly interested in; and (ii) that consequence is a paradoxical notion if truth is. (shrink)

Michelangelo thought that stone statues pre-exist their sculptors’ performance. Michelangelo’s view gives rise to a puzzle, which we call Michelangelo’s puzzle. Michelangelo’s puzzle looks structurally similar to so-called problems of material constitution ; so it is tempting to suppose that it can be similarly accounted for. This paper argues that the supposition is misguided. Michelangelo’s puzzle raises specific problems, which cannot be adequately dealt with unless one is prepared to give up either the natural view that stone sculptures are human (...) creations, or a very plausible principle concerning the persistence of middle-sized material objects. A tentative solution to the puzzle is provided, in which borders can play an ontological role in the making of material objects. This solution is intuitively more palatable than Michelangelo’s view, but is nonetheless at odds with a commonsensical, realist attitude towards material objects. Thus, Michelangelo’s puzzle poses a serious challenge to common sense, which is unparalleled by other problems of material constitution. (shrink)

Are identity criteria grounding principles? A prima facie answer to this question is positive. Specifically, two-level identity criteria can be taken as principles related to issues of identity among objects of a given kind compared with objects of a more basic kind. Moreover, they are grounding metaphysical principles of some objects with regard to others. In the first part of the paper we criticise this prima facie natural reading of identity criteria. This result does not mean that identity criteria could (...) not be taken as grounding principles. In the second part, we propose some basic steps towards a conceptual reading of grounding. Such a way of understanding it goes along with an epistemic reading of identity criteria. (shrink)

We reconsider the pragmatic interpretation of intuitionistic logic [21] regarded as a logic of assertions and their justi cations and its relations with classical logic. We recall an extension of this approach to a logic dealing with assertions and obligations, related by a notion of causal implication [14, 45]. We focus on the extension to co-intuitionistic logic, seen as a logic of hypotheses [8, 9, 13] and on polarized bi-intuitionistic logic as a logic of assertions and conjectures: looking at the (...) S4 modal translation, we give a de nition of a system AHL of bi-intuitionistic logic that correctly represents the duality between intuitionistic and co-intuitionistic logic, correcting a mistake in previous work [7, 10]. A computational interpretation of cointuitionism as a distributed calculus of coroutines is then used to give an operational interpretation of subtraction.Work on linear co-intuitionism is then recalled, a linear calculus of co-intuitionistic coroutines is de ned and a probabilistic interpretation of linear co-intuitionism is given as in [9]. Also we remark that by extending the language of intuitionistic logic we can express the notion of expectation, an assertion that in all situations the truth of p is possible and that in a logic of expectations the law of double negation holds. Similarly, extending co-intuitionistic logic, we can express the notion of conjecture that p, de ned as a hypothesis that in some situation the truth of p is epistemically necessary. (shrink)

We cast doubts on the suggestion, recently made by Graham Priest, that glut theorists may express disagreement with the assertion of A by denying A. We show that, if denial is to serve as a means to express disagreement, it must be exclusive, in the sense of being correct only if what is denied is false only. Hence, it can’t be expressed in the glut theorist’s language, essentially for the same reasons why Boolean negation can’t be expressed in such a (...) language either. We then turn to an alternative proposal, recently defended by Beall (in Analysis 73(3):438–445, 2013; Rev Symb Log, 2014), for expressing truth and falsity only, and hence disagreement. According to this, the exclusive semantic status of A, that A is either true or false only, can be conveyed by adding to one’s theory a shrieking rule of the form A & ~A |- \bot, where \bot entails triviality. We argue, however, that the proposal doesn’t work either. The upshot is that glut theorists face a dilemma: they can either express denial, or disagreement, but not both. Along the way, we offer a bilateral logic of exclusive denial for glut theorists—an extension of the logic commonly called LP. (shrink)

So-called Locke's thesis is the view that no two things of the same kind may coincide, that is, may be completely in the same place at the same time. A number of counter-examples to this view have been proposed. In this paper, some new and arguably more convincing counter-examples to Locke's thesis are presented. In these counter-examples, a particular entity (a string, a rope, a net, or similar) is interwoven to obtain what appears to be a distinct, thicker entity of (...) the same kind. It is argued that anyone who subscribes to certain standard metaphysical arguments, which are generally taken for granted in the debate about Locke's thesis, is virtually compelled to accept the counter-examples. (shrink)

Per il dialeteismo ci sono contraddizioni vere. Questa concezione filosofica ha assunto una forma chiara e definita a partire dal lavoro del filosofo e logico Graham Priest – uno dei suoi padri fondatori, nonché uno dei suoi più strenui difensori. Questo libro intende portare il dialeteismo all’attenzione di un ampio pubblico, che non sia solo quello degli addetti ai lavori. Il volume è suddiviso in due parti. La prima include le cinque lezioni su "Dialeteismo e storia della filosofia" tenute da (...) Priest e Filippo Casati a Padova nel 2016, in occasione del Corso di Eccellenza per il dottorato in filosofia dell’Università di Padova. La seconda contiene quattro contributi sul dialeteismo di autori italiani. (shrink)

In this paper we consider the emerging position in metaphysics that artifact functions characterize real kinds of artifacts. We analyze how it can circumvent an objection by David Wiggins (Sameness and substance renewed, 2001, 87) and then argue that this position, in comparison to expert judgments, amounts to an interesting fine-grained metaphysics: taking artifact functions as (part of the) essences of artifacts leads to distinctions between principles of activity of artifacts that experts in technology have not yet made. We show, (...) moreover, that our argument holds not only in the artifactual realm but also in biology: taking biological functions as (part of the) essences of organs leads to distinctions between principles of activity of organs that biological experts have not yet made. We run our argument on the basis of analyses of artifact and biological functions as developed in philosophy of technology and of biology, thus importing results obtained outside of metaphysics into the debate on ontological realism. In return, our argument shows that a position in metaphysics provides experts reason for trying to detect differences between principles of activities of artifacts and organs that have not been detected so far. (shrink)

According to strong composition as identity, the logical principles of one–one and plural identity can and should be extended to the relation between a whole and its parts. Otherwise, composition would not be legitimately regarded as an identity relation. In particular, several defenders of strong CAI have attempted to extend Leibniz’s Law to composition. However, much less attention has been paid to another, not less important feature of standard identity: a standard identity statement is true iff its terms are coreferential. (...) We contend that, if coreferentiality is dropped, indiscernibility is no help in making composition a genuine identity relation. To this aim, we analyse as a case study Cotnoir’s theory of general identity, in which indiscernibility is obtained thanks to a revisionary semantics and true identity statements are allowed to connect non-coreferential terms. We extend Cotnoir’s strategy for indiscernibility to the relation of comaternity, and we show that, neither in the case of composition nor in that of comaternity, indiscernibility contibutes to show that they are genuine identity relations. Finally, we compare Cotnoir’s approach with other versions of strong CAI endorsed by Wallace, Bøhn, and Hovda, and canvass the extent to which they violate coreferentiality. The comparative analysis shows that, in order to preserve coreferentiality, strong CAI is forced to adopt a non-standard semantic treatment of the singular/plural distinction. (shrink)

Logical orthodoxy has it that classical first-order logic, or some extension thereof, provides the right extension of the logical consequence relation. However, together with naïve but intuitive principles about semantic notions such as truth, denotation, satisfaction, and possibly validity and other naïve logical properties, classical logic quickly leads to inconsistency, and indeed triviality. At least since the publication of Kripke’s Outline of a theory of truth , an increasingly popular diagnosis has been to restore consistency, or at least non-triviality, by (...) restricting some classical rules. Our modest aim in this note is to briefly introduce the main strands of the current debate on paradox and logical revision, and point to some of the potential challenges revisionary approaches might face, with reference to the nine contributions to the present volume.For a recent introduction to non-classical theories of truth and other semantic notions, see the excellent Beall a .. (shrink)

What kind of reference (if any) do terms such as “pencil,” “chair,” “television,” and so on have? On the matter, a de-bate between directly referential theorists and descriptiv-ist theorists is open. It is largely acknowledged that natural kind terms (such as “water,” “gold,” “tiger,” etc.) are directly referential expressions (cf. Putnam,1975). That is, they are expressions whose reference is determined by their refer-ents' nature, independent of whether we know or will ever know what this nature is. However, it does not (...) seem like-wise convincing that all artifactual kind terms (like “pen-cil,” “chair,” “television,” etc.) semantically behave the same. Terms for artifactual kinds seem more likely to be subjected to a descriptivist view, that is, definable not by links to their extensions' nature but in terms of conjunctions or clusters of properties. In his celebrated “The Meaning of ‘Meaning’” (1975), Hilary Putnam originated the mentioned debate by arguing that artifactual kind terms also refer directly. Thus, the discussion ultimately revolves around establishing whether artifactual and natural kind terms are both directly referential expressions. The authors engaged in this debate have tried to argue in favor of (or against) Putnam's proposal by highlighting the similarities (or differences) between nat-ural vis-à-vis artifactual kind words and their respective ref-erents. This paper aims to provide a thorough and reasoned overview of the debate at stake, pointing out trends and problems associated with each proposed account. (shrink)

The paper considers sentences in which “now” occurs in initial position and shows that the meaning they convey differs from the meaning of sentences that are otherwise identical except for “now” occurring in final position. We argue that the occurrence of “now” in initial position triggers a particular kind of modal reading for the sentence to which the adverb is prefixed. A general notion of modal forcing is proposed to provide a uniform account of this kind of reading. Armed with (...) this account, we offer a solution to two tense-modal puzzles, which have to do with fatalism and the possibility of a changing past. (shrink)

Aim of the paper is to present a new logic of technical malfunction. The need for this logic is motivated by a simple-sounding philosophical question: Is a malfunctioning corkscrew, which fails to uncork bottles, nonetheless a corkscrew? Or in general terms, is a malfunctioning F, which fails to do what Fs do, nonetheless an F? We argue that ‘malfunctioning’ denotes the modifier Malfunctioning rather than a property, and that the answer depends on whether Malfunctioning is subsective or privative. If subsective, (...) a malfunctioning F is an F; if privative, a malfunctioning F is not an F. An intensional logic is required to raise and answer the question, because modifiers operate directly on properties and not on sets or individuals. This new logic provides the formal tools to reason about technical malfunction by means of a logical analysis of the sentence “a is a malfunctioning F”. (shrink)

The pragmatic logic of assertions shows a connection between ignorance and decidability. In it, we can express pragmatic factual ignorance and first-order ignorance as well as some of their variants. We also show how some pragmatic versions of second-order ignorance and of Rumsfeld-ignorance may be formulated. A specific variant of second-order ignorance is particularly relevant. This indicates a strong pragmatic version of ignorance of ignorance, irreducible to any previous form of ignorance, which defines limits to what can justifiably be asserted (...) about higher-order ignorance. Finally, we relate the justified assertion of second-order ignorance with scientific assertions. (shrink)

In this paper, we extend the expressive power of the logics K3, LP and FDE with anormality operator, which is able to express whether a for-mula is assigned a classical truth value or not. We then establish classical recapture theorems for the resulting logics. Finally, we compare the approach via normality operator with the classical collapse approach devisedby Jc Beall.

The topic of this paper is the notion of technical (as opposed to biological) malfunction. It is shown how to form the property being a malfunctioning F from the property F and the property modifier malfunctioning (a mapping taking a property to a property). We present two interpretations of malfunctioning. Both interpretations agree that a malfunctioning F lacks the dispositional property of functioning as an F. However, its subsective interpretation entails that malfunctioning Fs are Fs, whereas its privative interpretation entails (...) that malfunctioning Fs are not Fs. We chart various of their respective logical consequences and discuss some of the philosophical implications of both interpretations. (shrink)

The verb ‘to know’ can be used both in ascriptions of propositional knowledge and ascriptions of knowledge of acquaintance. In the formal epistemology literature, the former use of ‘know’ has attracted considerable attention, while the latter is typically regarded as derivative. This attitude may be unsatisfactory for those philosophers who, like Russell, are not willing to think of knowledge of acquaintance as a subsidiary or dependent kind of knowledge. In this paper we outline a logic of knowledge of acquaintance in (...) which ascriptions like ‘Mary knows Smith’ are regarded as formally interesting in their own right, remaining neutral on their relation to ascriptions of propositional knowledge. The resulting logical framework, which is based on Hintikka’s modal approach to epistemic logic, provides a fresh perspective on various issues and notions at play in the philosophical debate on acquaintance. (shrink)

In Mathematics is megethology Lewis reconstructs set theory combining mereology with plural quantification. He introduces megethology, a powerful framework in which one can formulate strong assumptions about the size of the universe of individuals. Within this framework, Lewis develops a structuralist class theory, in which the role of classes is played by individuals. Thus, if mereology and plural quantification are ontologically innocent, as Lewis maintains, he achieves an ontological reduction of classes to individuals. Lewis’work is very attractive. However, the alleged (...) innocence of mereology and plural quantification is highly controversial and has been criticized by several authors. In the present paper we propose a new approach to megethology based on the theory of plural reference developed in To be is to be the object of a possible act of choice. Our approach shows how megethology can be grounded on plural reference without the help of mereology. (shrink)

The notion of subject matter is a key concern of contemporary philosophy of language and logic. A central task for a theory of subject matter is to characterise the notion of sentential subject matter, that is, to assign to each sentence of a given language a subject matter that may count as its subject matter. In this paper, we elaborate upon David Lewis’ account of subject matter. Lewis’ proposal is simple and elegant but lacks a satisfactory characterisation of sentential subject (...) matter. Drawing on linguistic literature on focus and on the question under discussion, we offer a neo-Lewisian account of subject matter, which retains all the virtues of Lewis’ but also includes an attractive characterisation of sentential subject matter. (shrink)

In this paper we disambiguate the design stance as proposed by Daniel C. Dennett, focusing on its application to technical artefacts. Analysing Dennett’s work and developing his approach towards interpreting entities, we show that there are two ways of spelling out the design stance, one that presuppose also adopting Dennett’s intentional stance for describing a designing agent, and a second that does not. We argue against taking one of these ways as giving the correct formulation of the design stance in (...) Dennett’s approach, but propose to replace Dennett’s original design stance by two design stances: an intentional designer stance that incorporates the intentional stance, and a teleological design stance that does not. Our arguments focus on descriptions of technical artefacts: drawing on research in engineering, cognitive psychology and archaeology we show that both design stances are used for describing technical artefacts. A first consequence of this disambiguation is that a design stance, in terms of interpretative assumptions and in terms of the pragmatic considerations for adopting it, stops to be a stance that comes hierarchically between the physical stance and the intentional stance. A second consequence is that a new distinction can be made between types of entities in Dennett’s approach. We call entities to which the intentional designer stance is applied tools and entities to which the teleological design stance is applied instruments, leading to a differentiated understanding of, in particular, technical artefacts. (shrink)

Aim of the paper is to revise Boolos’ reinterpretation of second-order monadic logic in terms of plural quantification ([4], [5]) and expand it to full second order logic. Introducing the idealization of plural acts of choice, performed by a suitable team of agents, we will develop a notion of plural reference . Plural quantification will be then explained in terms of plural reference. As an application, we will sketch a structuralist reconstruction of second-order arithmetic based on the axiom of infinite (...) à la Dedekind, as the unique non-logical axiom. We will also sketch a virtual interpretation of the classical continuum involving no other infinite than a countable plurality of individuals. (shrink)

Classical mereology seems unable to characterise the identity conditions of word types. For example, the same letter types ordered differently result in different word types; but mereological fusions of the same letters are identical, regardless of the order of the letters. We show, however, that by combining classical mereology with plural logic one can give a definition of word types that satisfies the identity criteria of word types. This means that it is not necessary to abandon classical mereology in order (...) to give an analysis of the mereological structure of word types. (shrink)

Conflicts between our best philosophical theories (BPTs) and our common beliefs are widespread. For example, if eliminativism is our BPT, then our BPT conflicts with common beliefs about the existence of middle-sized composite artifacts. “Compatibilism” is the name usually given to a theoretical attitude, according to which, in the case of a conflict between BPT and a common belief P, we should try to find a reconciliation. The two major variants of compatibilism are “semantic compatibilism” (SC) and “cognitive compatibilism” (CC). (...) According to SC, to be reconciled with BPT is the “real” version of the content of our ordinary assertions; according to CC, to be reconciled with BPT is the mental state we are “really” in while thinking P. In this paper, we present a new kind of compatibilism, epistemic compatibilism (EC). According to EC, to be reconciled with BPT is the explanation of why we believe that P. After presenting EC, we will argue that it fares better than SC and CC for at least two related reasons: EC does not rely on any form of what we call semantic or cognitive “recarving”; thus, EC avoids some sceptical problems that aect the other two versions of compatibilism. (shrink)

The standard rule of single privative modification replaces privative modifiers by Boolean negation. This rule is valid, for sure, but also simplistic. If an individual a instantiates the privatively modified property (MF) then it is true that a instantiates the property of not being an F, but the rule fails to express the fact that the properties (MF) and F have something in common. We replace Boolean negation by property negation, enabling us to operate on contrary rather than contradictory properties. (...) To this end, we apply our theory of intensional essentialism, which operates on properties (intensions) rather than their extensions. We argue that each property F is necessarily associated with an essence, which is the set of the so-called requisites of F that jointly define F. Privation deprives F of some but not all of its requisites, replacing them by their contradictories. We show that properties formed from iterated privatives, such as being an imaginary fake banknote, give rise to a trifurcation of cases between returning to the original root property or to a property contrary to it or being semantically undecidable for want of further information. In order to determine which of the three forks the bearers of particular instances of multiply modified properties land upon we must examine the requisites, both of unmodified and modified properties. Requisites underpin our presuppositional theory of positive predication. Whereas privation is about being deprived of certain properties, the assignment of requisites to properties makes positive predication possible, which is the predication of properties the bearers must have because they have a certain property formed by means of privation. (shrink)

The book's aim is to give a working representation of what metaphysics is today. The historical contributions reveal the roots of metaphysical themes and how today's methods are linked to their Aristotelian and Leibnizian past. The volume also touches on the relationships between ontological and linguistic analysis, the questions of realism and ontological commitment, the nature of abstract objects, the existential meaning of particular quantification, the primitiveness of identity, the question of epistemic versus ontological vagueness, the necessity of origin, the (...) nature of natural necessity, the possibility of intermittent existence, the notion of a temporal part and its place in an account of persistence, the question of identity and change across time and possible worlds, and many more. Readership: A toolbox for any researcher in metaphysics and an essential source for any PhD student with ontological interests. (shrink)

Fictional truth, or truth in fiction/pretense, has been the object of extended scrutiny among philosophers and logicians in recent decades. Comparatively little attention, however, has been paid to its inferential relationships with time and with certain deliberate and contingent human activities, namely, the creation of fictional works. The aim of the paper is to contribute to filling the gap. Toward this goal, a formal framework is outlined that is consistent with a variety of conceptions of fictional truth and based upon (...) a specific formal treatment of time and agency, that of so-called stit logics. Moreover, a complete axiomatic theory of fiction-making TFM is defined, where fiction-making is understood as the exercise of agency and choice in time over what is fictionally true. The language \ of TFM is an extension of the language of propositional logic, with the addition of temporal and modal operators. A distinctive feature of \ with respect to other modal languages is a variety of operators having to do with fictional truth, including a ‘fictionality’ operator \ . Some applications of TFM are outlined, and some interesting linguistic and inferential phenomena, which are not so easily dealt with in other frameworks, are accounted for. (shrink)

ABSTRACT The paper criticizes an argument recently presented by Ross Cameron. The argument purports to show that, if time is gunky, and if changes in existence are underwritten by events of coming to be, then there are cases of indeterminate existence. The putative reason is that, if time is gunky, then events of coming to be cannot be instantaneous, and hence, changes in existence must be gradual, non-clear-cut. The paper argues that this argument conflates two different readings of “event of (...) coming to be”. Under one reading, the argument is unsound. Under the other, the argument is valid only if a further, nontrivial premise is added, which concerns the relation between time atoms, instants, and instantaneous events. (shrink)