This book is well known for its proof that many mathematical systems - including lattice theory and closure algebras - are undecidable. It consists of three treatises from one of the greatest logicians of all time: "A General Method in Proofs of Undecidability," "Undecidability and Essential Undecidability in Mathematics," and "Undecidability of the Elementary Theory of Groups.".

I ON THE PRIMITIVE TERM OF LOGISTICf IN this article I propose to establish a theorem belonging to logistic concerning some connexions, not widely known, ...

I hope to show that supervenience and determination, as I have here intuitively characterized them, are really different expressions of the same core idea which one may make more precise in a great number of different ways, depending on the interpretation one puts on the catchall parameters “cases”, “truth of kind P”and “truth of kind S”.

412 THE JOURNAL OF PHILOSOPHY There are theories that try, in my opinion unsuccessfully, to do just this. Tarski's theory, which restricts itself to cases in which truth is predicated of sentences of certain formal languages, is not one of them. Thus, Tarski cannot be seen.

A formal theory of truth, alternative to tarski's 'orthodox' theory, based on truth-value gaps, is presented. the theory is proposed as a fairly plausible model for natural language and as one which allows rigorous definitions to be given for various intuitive concepts, such as those of 'grounded' and 'paradoxical' sentences.

Gupta’s Rule of Revision theory of truth builds on insights to be found in Martin and Woodruff and Kripke in order to permanently deepen our understanding of truth, of paradox, and of how we work our language while our language is working us. His concept of a predicate deriving its meaning by way of a Rule of Revision ought to impact significantly on the philosophy of language. Still, fortunately, he has left me something to.

Supervenience in most of its guises entails necessary coextension. Thus theoretical supervenience entails nomically necessary coextension. Kim's result, thus strengthened, has yet to hit home. I suspect that many supervenience enthusiasts would cool at necessary coextension: they didn't mean to be saying anything quite so strong. Furthermore, nomically necessary coextension can be a good reason for property identification, leading to reducibility in principle. This again is more than many supervenience theorists bargained for. They wanted supervenience without reducibility. It is not (...) always available for this mediating role. (shrink)

Reprint of the original, first published in 1869.

Bringing together powerful new tools from set theory and the philosophy of language, this book proposes a solution to one of the few unresolved paradoxes from antiquity, the Paradox of the Liar. Treating truth as a property of propositions, not sentences, the authors model two distinct conceptions of propositions: one based on the standard notion used by Bertrand Russell, among others, and the other based on J.L. Austin's work on truth. Comparing these two accounts, the authors show that while the (...) Russellian conception of the relation between sentences, propositions, and truth is crucially flawed in limiting cases, the Austinian perspective has fruitful applications to the analysis of semantic paradox. In the course of their study of a language admitting circular reference and containing its own truth predicate, Barwise and Etchemendy also develop a wide range of model-theoretic techniques--based on a new set-theoretic tool, Peter Aczel's theory of hypersets--that open up new avenues in logical and formal semantics. (shrink)

The ancient puzzle of the Liar was shown by Tarski to be a genuine paradox or antinomy. I show, analogously, that certain puzzles of contemporary game theory are genuinely paradoxical, i.e., certain very plausible principles of rationality, which are in fact presupposed by game theorists, are inconsistent as naively formulated. ;I use Godel theory to construct three versions of this new paradox, in which the role of 'true' in the Liar paradox is played, respectively, by 'provable', 'self-evident', and 'justifiable'. I (...) also construct in modal operator logic a paradox involving reflexive empirical reasoning. Unlike the paradox of the Liar, the paradox of reflexive reasoning does not depend on self-reference. ;I consider various solutions to the Liar paradox and evaluate how well these solutions cope with the paradox of reflexive reasoning. I then formalize the solution to the paradoxes which I favor: the indexical-hierarchical approach, first sketched out by Charles Parsons and Tyler Burge. In this solution, occurrences of the predicate 'true' in sentence-tokens are contextually relativized to levels of a hierarchy. Drawing also on some brief remarks of Bertrand Russell and Charles Parsons, I develop an account of the kind of schematic generality needed for this theory to be statable. ;Finally, I demonstrate that the principles shown to be paradoxical are in fact presupposed by contemporary game theorists in their reliance on the notion of common knowledge or, more precisely, mutual belief. I create novel analyses of and corresponding solutions to several recalcitrant puzzles within game theory, including the "chain-store paradox". (shrink)

Now the thesis that the universal redness is the linguistic type ⋅red⋅ has the ring of absurdity. There are several ways in which this discomfort can be expressed I shall open my argument by formulating an objection which, by cutting deeper than most, leads to a firm foundation for a restatement and defense of the thesis.

I shall use upper case "Ki" to form the abstract singular term which stands to lower case "ki" as " fi-ness" stands to " fi." In other words, I shall drop the use of the suffix "-kind" in favor of this new device. Thus the platonistic counterpart of.

Developing and motivating the notion of supervenience. Investigating the relationship to reducibility and definability (equivalence, under certain conditions), and to microphysical determination.