"This book is valuable as expounding in full a theory of meaning that has its roots in the work of Frege and has been of the widest influence.

Føllesdal (1966 and 1969) claims that modal distinctions collapse, that is that p and Necessarily p are equivalent, in any system of modal logic that incorporates a standard theory of definite descriptions, like the one proposed by Carnap in M&N. I argue that his argument fails.

This note is a friendly amendment to Marti's analysis of the failure of Føllesdal's argument that modal distinctions collapse in Carnap's logic S2. Føllesdal's argument turns on the treatment of descriptions. Marti considers how modal descriptions, which Carnap banned, might be handled; she adopts an approach which blocks Føllesdal's argument, but requires a separate treatment of non-modal descriptions. I point out that a more general treatment of descriptions in S2 is possible, and indeed is implicit in Marti's informal discussion, and (...) that this treatment also blocks Føllesdal's argument. Further, I show by a semantic argument that no revised version of Føllesdal's argument could establish a collapse of modal distinctions. (shrink)

This paper outlines a framework for the abstract investigation of the concept of canonicity of names and of naming systems. Degrees of canonicity of names and of naming systems are distinguished. The structure of the degrees is investigated, and a notion of relative canonicity is defined. The notions of canonicity are formally expressed within a Carnapian system of second-order modal logic.

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)

In a recent paper Horsten embarked on a journey along the limits of the domain of the unknowable. Rather than knowability simpliciter, he considered a priori knowability, and by the latter he meant absolute provability, i.e. provability that is not relativized to a formal system. He presented an argument for the conclusion that it is not absolutely provable that there is a natural number of which it is true but absolutely unprovable that it has a certain property. The argument depends (...) on a description principle. I will argue that the latter principle implies the knowability of all arithmetical truths. Therefore, Horsten's argument is either sound but its conclusion is trivial, or his argument is unsound. (shrink)

This paper examines and discusses an argument for the collapse of modal distincions offered by Quine in "Reference and Modality" and in Word and Object that relies exclusively on a version of the Principle of Substitution. It is argued that the argument does not affect its historical targets: Carnap's treatment of modality, presented in Meaning and Necessity, and Church's Logic of Sense and Denotation, developed by Kaplan; nor does it affect a treatment of modality inspired in Frege's treatment of oblique (...) contexts. It is argued, nevertheless, that the immunity of those systems to Quine's argument depends on the success of their rejection of the Principle of Substitution presupposed by Quine. (shrink)

An appraisal of the current status of the modalities and of quine's arguments against them. The author accepts "quine's thesis," that one cannot quantify into referentially opaque contexts, And argues that nobody has succeeded in making sense of such quantification. However, It is shown that modal constructions, Being constructions on general terms and sentences, Can be referentially transparent and extensionally opaque and that consequently the collapse of modal distinctions warned against by quine in "word and object" can be avoided. This (...) combination of referential transparency and extensional opacity is just what quine means by essentialism, And the author therefore agrees with quine that quantified modal logic commits one to essentialism. (shrink)

This volume succeeds the same authors' well-known An Introduction to Modal Logic and A Companion to Modal Logic. We designate the three books and their authors NIML, IML, CML and H&C respectively. Sadly, George Hughes died partway through the writing of NIML.

This long-awaited book replaces Hughes and Cresswell's two classic studies of modal logic: _An Introduction to Modal Logic_ and _A Companion to Modal Logic_. _A New Introduction to Modal Logic_ is an entirely new work, completely re-written by the authors. They have incorporated all the new developments that have taken place since 1968 in both modal propositional logic and modal predicate logic, without sacrificing tha clarity of exposition and approachability that were essential features of their earlier works. The book takes (...) readers from the most basic systems of modal propositional logic right up to systems of modal predicate with identity. It covers both technical developments such as completeness and incompleteness, and finite and infinite models, and their philosophical applications, especially in the area of modal predicate logic. (shrink)

The subject of the first section is Carnapian modal logic. One of the things I will do there is to prove that certain description principles, viz. the ''self-predication principles'', i.e. the principles according to which a descriptive term satisfies its own descriptive condition, are theorems and that others are not. The second section will be devoted to Carnapian modal arithmetic. I will prove that, if the arithmetical theory contains the standard weak principle of induction, modal truth collapses to truth. Then (...) I will propose a different formulation of Carnapian modal arithmetic and establish that it is free of collapse. Noteworthy is that one can retain the standard strong principle of induction. I will occupy myself in the third section with Carnapian epistemic logic and arithmetic. Here too it is claimed that the standard weak principle of induction is invalid and that the alternative principle is valid. In the fourth and last section I will get back to the self-predication principles and I will point to some of the consequences if one adds them to Carnapian Epistemic arithmetic. The interaction of self-predication principles and the strong principle of induction results in a collapse of de re knowability. (shrink)