Quine and others have put many problems to quantified modal logic. Their purpose is to show the logic to be paradoxical or at least very peculiar. Many of these problems center around the interplay between modality, quantification and identity.

In "the meaning of 'meaning'," hilary putnam uses three "twin earth" examples to argue that natural kind terms do not have a sense. I argue that the first two only show that kind terms are like indexicals and that they are rigid designators but that this is compatible with having a sense. The third argument relies on a theory about the epistemological role of kind terms and the claim that there are no analytic truths about kinds that could arise from (...) a sense. (shrink)

The distinction between essential versus accidental properties has been characterized in various ways, but it is currently most commonly understood in modal terms: an essential property of an object is a property that it must have, while an accidental property of an object is one that it happens to have but that it could lack. Let’s call this the basic modal characterization, where a modal characterization of a notion is one that explains the notion in terms of necessity/possibility. In the (...) characterization just given of the distinction between essential and accidental properties, the use of the word “must” reflects the fact that necessity is invoked, while the use of the word “could” reflects that possibility is invoked. The notions of necessity and possibility are interdefinable: to say that something is necessary is to say that its negation is not possible; to say that something is possible is to say that its negation is not necessary; to say that an object must have a certain property is to say that it could not lack it; and to say that an object could have a certain property is to say that it is not the case that it must lack it. (shrink)

Truth of x (independently of any description of x) that it is f. A property f which holds of x but is not per se of x is said to hold per accidens of x. The essence of an individual is the sum of its per se properties. We can formulate the following: doctrine a: concrete individuals do not have essences though abstract entities do. Doctrine b: concrete individuals have essences but they do not individuate, whereas abstract entities have essences (...) which do individuate. Assumption i: we shall say that a thing exists insofar as it has an essence. Assumption ii: we shall say that we know a thing when we know what its per se properties are. We argue that plato held doctrine a and aristotle doctrine b (with assumptions i and ii). (edited). (shrink)

Let us call dispositional monism the view that all natural properties have their identities fixed purely by their dispositional features, that is, by the patterns of stimulus and response in which they participate. DM implies that natural properties are pure powers: things whose natures are fully identified by their roles in determining the potentialities of events to cause or be caused. As pure powers, properties are meant to lack quiddities in Black's sense. A property possesses a quiddity just in case (...) its identity is fixed by something independent of the causal–nomological roles it may enter into. Paradigmatically, a categorical property is thought of as a property whose identity is fixed by a quiddity .The key question about the viability of DM as a theory of properties is how properties can be pure powers devoid of any quiddity. Bird provides an answer. According to Bird , ‘all there is to a property is a matter of second-order relations to other properties’. The second-order relation is just the relation that a disposition, its stimulus condition, and a manifestation condition bear to each other. Call this relation SR. SR is not causation or physical necessitation. The latter relations are first-order relations between concrete events. SR is a second-order relation. Its possession by properties explains why events featuring those properties can enter into certain first-order relations of causation or necessitation.Bird's thought then is this: the sense in which properties have their identities fixed purely by their causal–nomological roles is that they are relationally constituted, where the relation doing the constituting is SR. 1 This thesis of relational constitution does not imply that natural properties are themselves relations. Nothing prevents the identity …. (shrink)

Might it be that world itself, independently of what we know about it or how we represent it, is metaphysically indeterminate? This article tackles in turn a series of questions: In what sorts of cases might we posit metaphysical indeterminacy? What is it for a given case of indefiniteness to be 'metaphysical'? How does the phenomenon relate to 'ontic vagueness', the existence of 'vague objects', 'de re indeterminacy' and the like? How might the logic work? Are there reasons for postulating (...) this distinctive sort of indefiniteness? Conversely, are there reasons for denying that there is indefiniteness of this sort? (shrink)

This is an encyclopedia entry on vagueness, focusing mainly on the opposition between re re and de dicta (linguistic or cognitive) accounts.

This paper is a reply to some of Scott Soames ' comments on my colloquium paper Marcus, Kripke, and the Origin of the New Theory of Reference. Except for the indicated parts added in May, 1995, this paper was written on December 16th–25th, 1994 as my reply to Soames for the APA colloquium in Boston, December 28, 1994. In this paper, I argue that Soames ' contention that Marcus is not one of the primary founders of contemporary nondescriptivist theories of (...) reference is false. Soames presents numerous arguments for his thesis that Marcus did not originate ideas later elaborated upon by Kripke, but his arguments are unsound; they are based in part on a misunderstanding of Marcus' theory and in part on an inadequate grasp of some of the key notions of the New Theory of Reference, such as the notion of a posteriori necessities and the notion of reference-fixing descriptions. (shrink)

In this paper I argue that questions about the semantics of rigid designation are commonly and illicitly run together with distinct issues, such as questions about the metaphysics of essence and questions about the theoretical legitimacy of the possible-worlds framework. I discuss in depth two case studies of this phenomenon – the first concerns the relation between rigid designation and reference, the second concerns the application of the notion of rigidity to general terms. I end by drawing out some conclusions (...) about the relations between rigid designation, semantic frameworks, reference, and essence. (shrink)

Despite the renown of ‘On Denoting’, much criticism has ignored or misconstrued Russell's treatment of scope, particularly in intensional, but also in extensional contexts. This has been rectified by more recent commentators, yet it remains largely unnoticed that the examples Russell gives of scope distinctions are questionable or inconsistent with his own philosophy. Nevertheless, Russell is right: scope does matter in intensional contexts. In Principia Mathematica, Russell proves a metatheorem to the effect that the scope of a single occurrence of (...) a description in an extensional context does not matter, provided existence and uniqueness conditions are satisfied. But attempts to eliminate descriptions in more complicated cases may produce an analysis with more occurrences of descriptions than featured in the analysand. Taking alternation and negation to be primitive (as in the first edition of Principia), this can be resolved, although the proof is non-trivial. Taking the Sheffer stroke to be primitive (as proposed by Russell in the second edition), with bad choices of scope the analysis fails to terminate. (shrink)

What is the source of logical and mathematical truth? This book revitalizes conventionalism as an answer to this question. Conventionalism takes logical and mathematical truth to have their source in linguistic conventions. This was an extremely popular view in the early 20th century, but it was never worked out in detail and is now almost universally rejected in mainstream philosophical circles. Shadows of Syntax is the first book-length treatment and defense of a combined conventionalist theory of logic and mathematics. It (...) argues that our conventions, in the form of syntactic rules of language use, are perfectly suited to explain the truth, necessity, and a priority of logical and mathematical claims, as well as our logical and mathematical knowledge. (shrink)

Esta enciclopédia abrange, de uma forma introdutória mas desejavelmente rigorosa, uma diversidade de conceitos, temas, problemas, argumentos e teorias localizados numa área relativamente recente de estudos, os quais tem sido habitual qualificar como «estudos lógico-filosóficos». De uma forma apropriadamente genérica, e apesar de o território teórico abrangido ser extenso e de contornos por vezes difusos, podemos dizer que na área se investiga um conjunto de questões fundamentais acerca da natureza da linguagem, da mente, da cognição e do raciocínio humanos, bem (...) como questões acerca das conexões destes com a realidade não mental e extralinguística. A razão daquela qualificação é a seguinte: por um lado, a investigação em questão é qualificada como filosófica em virtude do elevado grau de generalidade e abstracção das questões examinadas (entre outras coisas); por outro, a investigação é qualificada como lógica em virtude de ser uma investigação logicamente disciplinada, no sentido de nela se fazer um uso intenso de conceitos, técnicas e métodos provenientes da disciplina de lógica. O agregado de tópicos que constitui a área de estudos lógico-filosóficos é já visível, pelo menos em parte, no Tractatus Logico-Philosophicus de Ludwig Wittgenstein, uma obra publicada em 1921. E uma boa maneira de ter uma ideia sinóptica do território disciplinar abrangido por esta enciclopédia, ou pelo menos de uma porção substancial dele, é extrair do Tractatus uma lista dos tópicos mais salientes aí discutidos; a lista incluirá certamente tópicos do seguinte género, muitos dos quais se podem encontrar ao longo desta enciclopédia: factos e estados de coisas; objectos; representação; crenças e estados mentais; pensamentos; a proposição; nomes próprios; valores de verdade e bivalência; quantificação; funções de verdade; verdade lógica; identidade; tautologia; o raciocínio matemático; a natureza da inferência; o cepticismo e o solipsismo; a indução; as constantes lógicas; a negação; a forma lógica; as leis da ciência; o número. (shrink)

Principia Mathematic goes to great lengths to hide its order/type indices and to make it appear as if its incomplete symbols behave as if they are singular terms. But well-hidden as they are, we cannot understand the proofs in Principia unless we bring them into focus. When we do, some rather surprising results emerge ? which is the subject of this paper.

The title is an allusion to the fact that, traditionally, propositions have served at least two distinct functions in philosophy, even though these functions have not usually been distinguished. Propositions have been invoked as the ‘meanings’ or ‘intensions’ of sentences and as the objects of propositional attitudes. Thus the proposition that Socrates is wise is the meaning of the English sentence, ‘Socrates is wise,’ and is what Charles believes when he believes that Socrates is wise. ‘Means that’ and ‘believes that’ (...) take the same kind of object. I shall argue, first, that there are two quite different functions here and it takes two quite different kinds of proposition to serve these distinct functions. The second thing I want to do is examine the suggestion that we can treat propositions as sets of possible worlds. There is a serious difficulty here, and so I shall want to turn that idea on its side: I shall define possible worlds as sets of G-propositions and then define E-propositions as sets of possible worlds. (shrink)

In the Twentieth Century, Logic and Philosophy of Language are two of the few areas of philosophy in which philosophers made indisputable progress. For example, even now many of the foremost living ethicists present their theories as somewhat more explicit versions of the ideas of Kant, Mill, or Aristotle. In contrast, it would be patently absurd for a contemporary philosopher of language or logician to think of herself as working in the shadow of any figure who died before the Twentieth (...) Century began. Advances in these disciplines make even the most unaccomplished of its practitioners vastly more sophisticated than Kant. There were previous periods in which the problems of language and logic were studied extensively (e.g. the medieval period). But from the perspective of the progress made in the last 120 years, previous work is at most a source of interesting data or occasional insight. All systematic theorizing about content that meets contemporary standards of rigor has been done subsequently. (shrink)

Certains philosophes se sentent plus à l'aise dans l'essai ou l'article que dans le livre. Il arrive que même quand leurs essais sont des classiques, discutes abondamment depuis des années, la parution en volume tarde à venir. Mais quand elle vient, le recueil s'impose d'emblée comme un ouvrage majeur, et révèle la cohérence de la démarche de l'auteur et le caractère impressionnant de ses contributions. Ce livre de Ruth Barcan Marcus est de ceux-là.

This paper argues for a conditional claim concerning a famous argument—developed by Church in elucidation of some remarks by Frege to the effect that the bedeutung of a sentence is the sentence’s truth-value—the Frege–Gödel–Church argument, or FGC for short. The point we make is this :if, and just to the extent that, Arthur Smullyan’s argument against Quine's use of FGC is sound, then essentially the same rejoinder disposes also of Davidson's use of FGC against ‘correspondence’ theories of truth. We thus (...) dispute a contention by Professor Davidson that it is coherent to accept that Smullyan’s rejoinder takes away the force of Quine’s version of FGC, while still consistently using FGC to establish that if true sentences (or utterances) correspond to anything, they all correspond to the same thing. We show that the differences between the cases discussed by Smullyan and Davidson’s version of FGC on which Davidson relies for his contention are irrelevant to the point under dispute. (shrink)

Remember the story of the most-most? It’s the story of that club in New York where people are the most of every type. There is the hairiest bald man and the baldest hairy man; the shortest giant and the tallest dwarf; the smartest idiot and the stupidest wise man. They are all there, including honest thieves and crippled acrobats. On Saturday night they have a party, eat, drink, dance. Then they have a contest. “And if you can tell the hairiest (...) bald man from the baldest hairy man—we are told—you get a prize.”. (shrink)

Some philosophers have argued that the vagueness exhibited by names and descriptions such as ‘Mount Everest’, ‘Downtown Manhattan’, or ‘that cloud in the sky’ is ultimately ontological: they are vague because they refer to vague objects, objects with fuzzy boundaries. I take the opposite stand and argue for the view that all vagueness is semantic. There is no such thing as a vague mountain. Rather, there are many things where we conceive the mountain to be, each with its precise boundary, (...) and when we say ‘Everest’ we are just being vague as to which thing we are referring to. This paper defends this view against some plausible objections. (shrink)

Some have argued that the vagueness exhibited by geographic names and descriptions such as ‘Albuquerque’, ‘the Outback’, or ‘Mount Everest’ is ultimately ontological: these terms are vague because they refer to vague objects, objects with fuzzy boundaries. I take the opposite stand and hold the view that geographic vagueness is exclusively semantic, or conceptual at large. There is no such thing as a vague mountain. Rather, there are many things where we conceive a mountain to be, each with its precise (...) boundary, and when we say ‘Everest’ we are just being vague as to which thing we are referring to. This paper defends this view against some plausible objections. (shrink)

The debate about the ontological innocence of mereology has generally been framed as a debate about the plausibility of Universal Fusion. Ontologically loaded fusions must be more than the sum of their parts, and this seems to violate parsimony if fusion is universal. Less attention has been paid to the question of what sort of emergence mereological fusions must exhibit if they are irreducible to their parts. The philosophy of science literature provides several models of such strong emergence. Examining those (...) models suggests that the difficulty with emergent fusions has at least as much to do with extensionality as it does with Universal Fusion. Some accounts of emergence fail to ensure irreducibility when combined with extensional mereologies. The most promising model for the strong emergence of ontologically loaded fusions fails to validate Anti-Symmetry, which naturally leads to failures of extensionality. These results suggest that the focus on Universal Fusion may have been misplaced. (shrink)

Lewis’ analysis of modality faces a problem in that it appears to confer unintended truth values to certain modal claims about the pluriverse: e.g. ‘It is possible that there are many worlds’ is false when we expect truth. This is the problem of advanced modalizing. Divers presents a principled solution to this problem by treating modal modifiers as semantically redundant in some such cases. However, this semantic move does not deal adequately with advanced de re modal claims. Here, we motivate (...) and detail a comprehensive semantics for advanced modalizing de dicto and de re. The generalized semantic feature of the initial solution is not redundancy but absence from counterpart-theoretic translations of world-constrictions. (shrink)

There is a certain argument against the principle of the indiscernibility of identicals, or the thesis that whatever is true of a thing is true of anything identical with that thing. In this argument, PInI is used together with the self-evident principle of the necessity of self-identity to reach the conclusion, which is held to be paradoxical and, thus, fatal to PInI. My purpose is to show that the argument in question does not have this consequence. Further, I argue that (...) PInI is a universally valid principle which can be used to prove the necessity of identity. (shrink)

This paper argues for a conditional claim concerning a famous argument—developed by Church in elucidation of some remarks by Frege to the effect that the bedeutung of a sentence is the sentence’s truth-value—the Frege–Gödel–Church argument, or FGC for short. The point we make is this :if, and just to the extent that, Arthur Smullyan’s argument against Quine's use of FGC is sound, then essentially the same rejoinder disposes also of Davidson's use of FGC against ‘correspondence’ theories of truth. We thus (...) dispute a contention by Professor Davidson that it is coherent to accept that Smullyan’s rejoinder takes away the force of Quine’s version of FGC, while still consistently using FGC to establish that if true sentences (or utterances) correspond to anything, they all correspond to the same thing. We show that the differences between the cases discussed by Smullyan and Davidson’s version of FGC on which Davidson relies for his contention are irrelevant to the point under dispute. (shrink)

The source, status, and significance of the derivation of the necessity of identity at the beginning of Kripke’s lecture “Identity and Necessity” is discussed from a logical, philosophical, and historical point of view.

This paper traces the development of Quine's ontological ideas throughout his early logical work in the period before 1948. It shows that his ontological criterion critically depends on this work in logic. The use of quantifiers as logical primitives and the introduction of general variables in 1936, the search for adequate comprehension axioms, and problems with proper classes, all forced Quine to consider ontological questions. I also show that Quine's rejection of intensional entities goes back to his generalisation of Principia (...) Mathematica in 1932. (shrink)

Williamson has forcefully argued that Fitch's argument shows that the domain of the unknowable is non-empty. And he exhorts us to make more inroads into the land of the unknowable. Concluding his discussion of Fitch's argument, he writes: " Once we acknowledge that [the domain of the unknowable] is non-empty, we can explore more effectively its extent. … We are only beginning to understand the deeper limits of our knowledge. " I shall formulate and evaluate a new argument concerning the (...) domain of the unknowable. It is an argument about knowability. More specifically, it is an argument about what we can know about the natural numbers. Since the domain of discourse will be the natural numbers structure, the notion of knowability can for the purposes of the argument be identified with a priori knowability or – which amounts to the same thing – absolute provability .Suppose, for a reductio, that there exists a property θ of natural numbers such that it is provable that for some natural number n, θ is true but unprovable. …. (shrink)

This is the introductory essay to a collection commemorating the 100th anniversary of the publication in Mind of Bertrand Russell’s paper ‘On Denoting’.

What does it mean for a text to be transparent? If in order to be considered such, as the Oxford English Dictionary among others tells us, a thing must either be ‘easily seen’ or else ‘easily seen through’, what does this contradiction embedded into the term mean for the reader of transparent things? Vladimir Nabokov engages precisely this line of inquiry in the candidly named 1972 Transparent Things, his penultimate text before his death in 1977. In doing so, Nabokov also (...) articulates a particular understanding of and attraction to transparency which has permeated his body of works since at least the 1920s and which, in this emphatic iteration, serves to complicate the notion of any stability in the roles of ‘authors’ and ‘readers’; to dismantle the dichotomous logic of the categories of ‘surface’ and ‘depth’; and finally to advocate for that which appears as ‘surface’ as the space where writing, reading and criticism is at its most fluid, inventive and kaleidoscopic. (shrink)

Alonzo Church (1903–1995) was a renowned mathematical logician, philosophical logician, philosopher, teacher and editor. He was one of the founders of the discipline of mathematical logic as it developed after Cantor, Frege and Russell. He was also one of the principal founders of the Association for Symbolic Logic and the Journal of Symbolic Logic. The list of his students, mathematical and philosophical, is striking as it contains the names of renowned logicians and philosophers. In this article, we focus primarily on (...) Church’s philosophical contributions. (For an account of his life and academic history see the Introduction to The Collected Works of Alonzo Church (2019).) However, we also discuss his mathematical results when it is desirable to do so in order to pursue a philosophical issue. (shrink)

We tend to talk about (refer to, quantify over) parts in the same way in which we talk about whole objects. Yet a part is not something to be included in an inventory of the world over and above the whole to which it belongs, and a whole is not something to be included in the inventory over and above its constituent parts. This paper is an attempt to clarify a way of dealing with this tension which may be labeled (...) the Minimalist View: An element in the field of a part-whole relation is to be included in an inventory of the world if and only if it does not overlap any distinct element that is itself included in the inventory. (shrink)

Jaakko hintikka claims to have explained the (only quasi-Logical) absurdity of (m) "p but I don't believe that p". I argue that, While his explicans (b) is true so far as it goes, It is as badly in need of explanation as is (m) itself. I offer two lines of reasoning designed to account for (b) and further to localize the absurdity of (m); but I do not claim to have given the whole story.

We tend to talk about parts in the same way in which we talk about whole objects. Yet a part is not something to be included in an inventory of the world over and above the whole to which it belongs, and a whole is not something to be included in an inventory over and above its own parts. This paper is an attempt to clarify a way of dealing with this tension which may be labeled the Minimalist View: an (...) element in the field of a part‐whole relation is to be included in an inventory of the world if, and only if, it does not overlap any other element that is itself included in the inventory. As it turns out, a clarification of this view involves both a defense of mereological extensionality and an account of the topological distinction between detached and undetached parts. (shrink)

I argue that counterpart theory is incompatible with truthmaking supervenience, the thesis that truth supervenes on what there is and how things are. I further argue that David Lewis’s “qua” strategy for providing ontologically innocent and Humean-friendly truthmakers for predications faces a number of difficulties. I propose and assess various solutions to those difficulties, each of which comes at the cost of sacrificing one of the two main virtues of the qua strategy.