In 1911, Bertrand Russell began a historically formative interchange about the nature of logic and cognition with his student, Ludwig Wittgenstein. In 1913, Russell set to work on a manuscript, the "Theory of Knowledge", designed to move from the analysis of perception to judgement and on to knowledge of the world. After Wittgenstein interrupted Russell's daily writing with a series of objections to his doctrine of judgement and conception of logic, Russell abandoned his project in despair, leaving it unfinished. His subsequent work can be understood largely as an attempt to assimilate and respond to Wittgenstein's challenge in 1913. "Russell and Wittgenstein on the Nature of Judgement" is the first book-length treatment of Russell's decisive 1913 exchanges with Wittgenstein. Rosalind Carey incorporates little-known notes and diagrams into a new analysis of the problems Russell was facing. She also evaluates the numerous interpretations of Russell's positions and Wittgenstein's objections to them. The result is a new perspective on both these great thinkers, at a crucial point in the development of twentieth-century philosophy.

This book focuses on logic and logical language. It examines different types of words, terms and propositions in detail. While discussing the nature of propositions, it illustrates the procedures used to determine the truth and falsity of a proposition, and the validity and invalidity of an argument. In addition, the book provides a clear exposition of the pure and mixed form of syllogism with suitable examples. The book encompasses sentential logic, predicate logic, symbolic logic, induction and set theory topics. The book is designed to serve all those involved in teaching and learning courses on logic. It offers a valuable resource for students and researchers in philosophy, mathematics and computer science disciplines. Given its scope, it is an essential read for everyone interested in logic, language, formulation of the hypotheses for the scientific enquiries and research studies, and judging valid and invalid arguments in the natural language discourse.

ways of doing it, but it is wrong to project it far into the past: it did not exist at the turn of the century and only became clearly apparent after the Second World War. I recently taught at an American university on the his tory of philosophy from Balzano to Husserl. The course title had to come from a fixed pool and gave trouble. Was it philosophical logic, the nine teenth century, or phenomenology? A logic title would connote over this period Frege, Russell, Carnap, perhaps a mention of Boole: not continental enough. The nineteenth century? The century of Kant's successors: Fichte, Hegel, Schopenhauer, Feuer bach, Marx, Nietzsche? What have they to do with Balzano, Lotze, Brentano, Meinong, Husserl and Twardowski? Even tually 'Phenomenology' was chosen, misdescribing more than half of the course. That illustrates the problems one faces in trying to work against the picture of the period which is ingrained in minds and syllabuses. This book arises from my efforts to combat that picture. I backed into writing about the history of recent philosophy rather than setting out to do so. The beginning was chance. In Manchester in the early seventies, at a time when most English philosophy departments breathed re cycled Oxford air, the intellectual atmosphere derived from Cambridge and Warsaw, spiced with a breath of Freiburg and Paris."

Logical consequence is the relation that obtains between premises and conclusion(s) in a valid argument. Orthodoxy has it that valid arguments are necessarily truth-preserving, but this platitude only raises a number of further questions, such as: how does the truth of premises guarantee the truth of a conclusion, and what constraints does validity impose on rational belief? This volume presents thirteen essays by some of the most important scholars in the field of philosophical logic. The essays offer ground-breaking new insights into the nature of logical consequence; the relation between logic and inference; how the semantics and pragmatics of natural language bear on logic; the relativity of logic; and the structural properties of the consequence relation.

This book attempts to explicate and expand upon Frank Ramsey's notion of the realistic spirit. In so doing, it provides a systematic reading of his work, and demonstrates the extent of Ramsey's genius as evinced by both his responses to the Tractatus Logico-Philosophicus, and the impact he had on Wittgenstein's later philosophical insights.

This book examines the nature, sources, and implications of fallacies in philosophical reasoning. In doing so, it illustrates and evaluates various historical instances of this phenomenon. There is widespread interest in the practice and products of philosophizing, yet the important issue of fallacious reasoning in these matters has been effectively untouched. Nicholas Rescher fills this gap by presenting a systematic account of the principal ways in which philosophizing can go astray.

The present volume of the "Handbook of the History of Logic" is designed to establish 19th century Britain as a substantial force in logic, developing new ideas, some of which would be overtaken by, and other that would anticipate, the century's later capitulation to the mathematization of logic.
"British Logic in the Nineteenth Century" is indispensable reading and a definitive research resource for anyone with an interest in the history of logic.
- Detailed and comprehensive chapters covering the entire range of modal logic
- Contains the latest scholarly discoveries and interpretative insights that answer many questions in the field of logic

Wittgenstein's Tractatus Logico-Philosophicus, first published in 1921, has had a profound influence on modern philosophic thought. Prototractatus is a facsimile reproduction of an early version of Tractatus, only discovered in 1965. The original text has a parallel English translation and the text is edited to indicate all relevant deviations from the final version.

This book features more than 20 papers that celebrate the work of Hajnal Andreka and Istvan Nemeti. It illustrates an interaction between developing and applying mathematical logic. The papers offer new results as well as surveys in areas influenced by these two outstanding researchers. They also provide details on the after-life of some of their initiatives. Computer science connects the papers in the first part of the book. The second part concentrates on algebraic logic. It features a range of papers that hint at the intricate many-way connections between logic, algebra, and geometry. The third part explores novel applications of logic in relativity theory, philosophy of logic, philosophy of physics and spacetime, and methodology of science. They include such exciting subjects as time travelling in emergent spacetime. The short autobiographies of Hajnal Andreka and Istvan Nemeti at the end of the book describe an adventurous journey from electric engineering and Maxwell's equations to a complex system of computer programs for designing Hungary's electric power system, to exploring and contributing deep results to Tarskian algebraic logic as the deepest core theory of such questions, then on to applications of the results in such exciting new areas as relativity theory in order to rejuvenate logic itself.

Individual objects have potentials: paper has the potential to burn, an acorn has the potential to turn into a tree, some people have the potential to run a mile in less than four minutes. Barbara Vetter provides a systematic investigation into the metaphysics of such potentials, and an account of metaphysical modality based on them. In contemporary philosophy, potentials have been recognized mostly in the form of so-called dispositions: solubility, fragility, and so on. Vetter takes dispositions as her starting point, but argues for and develops a more comprehensive conception of potentiality. She shows how, with this more comprehensive conception, an account of metaphysical modality can be given that meets three crucial requirements: (1) Extensional correctness: providing the right truth-values for statements of possibility and necessity; (2) formal adequacy: providing the right logic for metaphysical modality; and (3) semantic utility: providing a semantics that links ordinary modal language to the metaphysics of modality. The resulting view of modality is a version of dispositionalism about modality: it takes modality to be a matter of the dispositions of individual objects (and, crucially, not of possible worlds). This approach has a long philosophical tradition going back to Aristotle, but has been largely neglected in contemporary philosophy. In recent years, it has become a live option again due to the rise of anti-Humean, powers-based metaphysics. The aim of Potentiality is to develop the dispositionalist view in a way that takes account of contemporary developments in metaphysics, logic, and semantics.

Deflationist accounts of truth are widely held in contemporary philosophy: they seek to show that truth is a dispensable concept with no metaphysical depth. However, logical paradoxes present problems for deflationists that their work has struggled to overcome. In this volume of fourteen original essays, a distinguished team of contributors explore the extent to which, if at all, deflationism can accommodate paradox. The volume will be of interest to philosophers of logic, philosophers of language, and anyone working on truth.
Contributors include Bradley Armour-Garb, Jody Azzouni, JC Beall, Hartry Field, Christopher Gauker, Michael Glanzberg, Dorothy Grover, Anil Gupta, Volker Halbach, Leon Horsten, Paul Horwich, Graham Priest, Greg Restall, and Alan Weir

It is the aim of the present study to introduce the reader to the ways of thinking of those contemporary philosophers who apply the tools of symbolic logic to classical philosophical problems. Unlike the "conti nental" reader for whom this work was originally written, the English speaking reader will be more familiar with most of the philosophers dis cussed in this book, and he will in general not be tempted to dismiss them indiscriminately as "positivists" and "nominalists." But the English version of this study may help to redress the balance in another respect. In view of the present emphasis on ordinary language and the wide spread tendency to leave the mathematical logicians alone with their technicalities, it seems not without merit to revive the interest in formal ontology and the construction of formal systems. A closer look at the historical account which will be given here, may convince the reader that there are several points in the historical develop ment whose consequences have not yet been fully assessed: I mention, e. g., the shift from the traditional three-level semantics of sense and deno tation to the contemporary two-level semantics of representation; the relation of extensional structure and intensional content in the extensional systems of Wittgenstein and Carnap; the confusing changes in labelling the different kinds of analytic and apriori true sentences; etc. Among the philosophically interesting tools of symbolic logic Lesniewski's calculus of names deserves special attention."

Composition is the relation between a whole and its parts-the parts are said to compose the whole; the whole is composed of the parts. But is a whole anything distinct from its parts taken collectively? It is often said that 'a whole is nothing over and above its parts'; but what might we mean by that? Could it be that a whole just is its parts? This collection of essays is the first of its kind to focus on the relationship between composition and identity. Twelve original articles-written by internationally renowned scholars and rising stars in the field-argue for and against the controversial doctrine that composition is identity. An editor's introduction sets out the formal and philosophical groundwork to bring readers to the forefront of the debate.

Axiomatic Formal Ontology is a fairly comprehensive systematic treatise on general metaphysics. The axiomatic method is applied throughout the book. Its main theme is the construction of a general non-set-theoretical theory of intensional entities. Other important matters discussed are the metaphysics of modality, the nature of actual existence, mereology and the taxonomy of entities.

Roy T Cook examines the Yablo paradox-a paradoxical, infinite sequence of sentences, each of which entails the falsity of all others later than it in the sequence-with special attention paid to the idea that this paradox provides us with a semantic paradox that involves no circularity. The three main chapters of the book focus, respectively, on three questions that can be (and have been) asked about the Yablo construction. First we have the Characterization Problem, which asks what patterns of sentential reference (circular or not) generate semantic paradoxes. Addressing this problem requires an interesting and fruitful detour through the theory of directed graphs, allowing us to draw interesting connections between philosophical problems and purely mathematical ones. Next is the Circularity Question, which addresses whether or not the Yablo paradox is genuinely non-circular. Answering this question is complicated: although the original formulation of the Yablo paradox is circular, it turns out that it is not circular in any sense that can bear the blame for the paradox. Further, formulations of the paradox using infinitary conjunction provide genuinely non-circular constructions. Finally, Cook turns his attention to the Generalizability Question: can the Yabloesque pattern be used to generate genuinely non-circular variants of other paradoxes, such as epistemic and set-theoretic paradoxes? Cook argues that although there are general constructions-unwindings-that transform circular constructions into Yablo-like sequences, it turns out that these sorts of constructions are not 'well-behaved' when transferred from semantic puzzles to puzzles of other sorts. He concludes with a short discussion of the connections between the Yablo paradox and the Curry paradox.

Leibniz published the Dissertation on Combinatorial Art in 1666. This book contains the seeds of Leibniz's mature thought, as well as many of the mathematical ideas that he would go on to further develop after the invention of the calculus. It is in the Dissertation, for instance, that we find the project for the construction of a logical calculus clearly expressed for the first time. The idea of encoding terms and propositions by means of numbers, later developed by Kurt Goedel, also appears in this work. In this text, furthermore, Leibniz conceives the possibility of constituting a universal language or universal characteristic, a project that he would pursue for the rest of his life. Mugnai, van Ruler, and Wilson present the first full English translation of the Dissertation, complete with a critical introduction and a comprehensive commentary.

When asked in 1962 on what he was working Kazimierz Ajdukiewicz replied: Several years ago Polish Scientific Publishers suggested that I pre pare a new edition of The Logical Foundations of Teaching, which I wrote 1 before 1939 as a contribution to The Encyclopaedia of Education. It was a small booklet covering elementary information about logical semantics and scientific methodology, information which in my opinion was necessary as a foundation of teaching and as an element of the education of any teacher. When I recently set to preparing the new edition, I rewrote practically everything, and a booklet of some 100 pages swelled into a bulky volume almost five times bigger. The issues have remained practically the same, but they are now analysed much more thoroughly and the threshold of difficulty is much higher now. The main stress has been laid on the methods used in the empirical sciences, and within that field, on the theory of measurement and the methods of statistical inference. I am now working on the last chapter of the book, concerned with explanation procedures and theory construction in the empirical sciences. When that book, which I intend to entitle Pragmatic Logic, is com pleted I intend to prepare for the press Vol. 2 of my minor writings, 2 Language and Cognition, which will cover some of my post-war pa pers."

1. STRUCTURE AND REFERENCES 1.1. The main part of the dictionary consists of alphabetically arranged articles concerned with basic logical theories and some other selected topics. Within each article a set of concepts is defined in their mutual relations. This way of defining concepts in the context of a theory provides better understand ing of ideas than that provided by isolated short defmitions. A disadvantage of this method is that it takes more time to look something up inside an extensive article. To reduce this disadvantage the following measures have been adopted. Each article is divided into numbered sections, the numbers, in boldface type, being addresses to which we refer. Those sections of larger articles which are divided at the first level, i.e. numbered with single numerals, have titles. Main sections are further subdivided, the subsections being numbered by numerals added to the main section number, e.g. I, 1.1, 1.2, ..., 1.1.1, 1.1.2, and so on. A comprehensive subject index is supplied together with a glossary. The aim of the latter is to provide, if possible, short defmitions which sometimes may prove sufficient. As to the use of the glossary, see the comment preceding it."

This book is the first to provide a critical history of analytic philosophy from its inception in the late nineteenth century to the present day. Quentin Smith focuses on the connections between the four leading movements in analytic philosophy -- logical realism, logical positivism, ordinary language analysis, and linguistic essentialism -- and corresponding twentieth-century theories of ethics and of religion. Through a critical evaluation of each school's theoretical positions, Smith counters the widespread view of analytic philosophy as indifferent to important questions about fight and wrong and human meaning. He argues that analytic philosophy throughout its history has revolved around the central issues of existence, and he offers a new ethics and philosophy of religion.

The author develops a positive ethical theory based on a method of ethics first formulated by Robert Adams. Smith's theory belongs to the tradition of perfectionism or self-realization ethics and builds on Thomas Hurka's recent theory of perfectionism. In his consideration of philosophy of religion, Smith concludes that there is a sound "logical argument from evil" that takes into account Alvin Plantinga's free-will defense and undermines monotheism, paving the way to a naturalistic pantheism.

"Smith's book is original not only in intent but frequently in the detailed argument involved in evaluating the merits of the philosophies of language and their implications for ethics and philosophy of religion". -- John F. Post, Vanderbilt University

Terence Parsons presents a new study of the development and logical complexity of medieval logic. Basic principles of logic were used by Aristotle to prove conversion principles and reduce syllogisms. Medieval logicians expanded Aristotle's notation in several ways, such as quantifying predicate terms, as in 'No donkey is every animal', and allowing singular terms to appear in predicate position, as in 'Not every donkey is Brownie'; with the enlarged notation come additional logical principles. The resulting system of logic is able to deal with relational expressions, as in De Morgan's puzzles about heads of horses. A crucial issue is a mechanism for dealing with anaphoric pronouns, as in 'Every woman loves her mother'. Parsons illuminates the ways in which medieval logic is as rich as contemporary first-order symbolic logic, though its full potential was not envisaged at the time. Along the way, he provides a detailed exposition and examination of the theory of modes of common personal supposition, and the useful principles of logic included with it. An appendix discusses the artificial signs introduced in the fifteenth century to alter quantifier scope.

This monograph is a detailed study, and systematic defence, of the Growing Block Theory of time (GBT), first conceived by C.D. Broad. The book offers a coherent, logically perspicuous and ideologically lean formulation of GBT, defends it against the most notorious objections to be found in the extant philosophical literature, and shows how it can be derived from a more general theory, consistent with relativistic spacetime, on the pre-relativistic assumption of an absolute and total temporal order. The authors devise axiomatizations of GBT and its competitors which, against the backdrop of a shared quantified tense logic, significantly improves the prospects of their comparative assessment. Importantly, neither of these axiomatizations involves commitment to properties of presentness, pastness or futurity. The authors proceed to address, and defuse, a number of objections that have been marshaled against GBT, including the so-called epistemic objection according to which the theory invites skepticism about our temporal location. The challenge posed by relativistic physics is met head-on, by replacing claims about temporal variation by claims about variation across spacetime. The book aims to achieve the greatest possible rigor. The background logic is set out in detail, as are the principles governing the notions of precedence and temporal location. The authors likewise devise a novel spacetime logic suited for the articulation, and comparative assessment, of relativistic theories of time. The book comes with three technical appendices which include soundness and completeness proofs for the systems corresponding to GBT and its competitors, in both their pre-relativistic and relativistic forms. The book is primarily directed at researchers and graduate students working on the philosophy of time or temporal logic, but is of interest to metaphysicians and philosophical logicians more generally.