The Logic Manual is a clear and concise introduction to logic for beginning philosophy students. It offers a complete introductory course, guiding the reader carefully through the topics in logic that are most important for the study of philosophy. It covers propositional and predicate logic with and without identity. It includes an account of the semantics of these languages including definitions of truth and satisfaction. Natural deduction is used as a proof system. Volker Halbach introduces the essential concepts through examples and informal explanations as well as through abstract definitions.
The Logic Manual provides the best entry to the general abstract way of thinking about language, logic, and semantics which is characteristic of contemporary philosophy. Exercises, examples, and sample examination papers are provided on an accompanying website.

Our experience of objects (and consequently our theorizing about them) is very rich. We perceive objects as possessing individuation conditions. They appear to have boundaries in space and time, for example, and they appear to move independently of a background of other objects or a landscape. In Ontology Without Boundaries Jody Azzouni undertakes an analysis of our concept of object, and shows what about that notion is truly due to the world and what about it is a projection onto the world of our senses and thinking. Location and individuation conditions are our product: there is no echo of them in the world. Features, the ways that objects seem to be, aren't projections. Azzouni shows how the resulting austere metaphysics tames a host of ancient philosophical problems about constitution ("Ship of Theseus," "Sorities"), as well as contemporary puzzles about reductionism. In addition, it's shown that the same sorts of individuation conditions for properties, which philosophers use to distinguish between various kinds of odd abstracta-universals, tropes, and so on, are also projections. Accompanying our notion of an object is a background logic that makes cogent ontological debate about anything from Platonic objects to Bigfoot. Contemporary views about this background logic ("quantifier variance") make ontological debate incoherent. Azzouni shows how a neutral interpretation of quantifiers and quantifier domains makes sense of both philosophical and pre-philosophical ontological debates. Azzouni also shows how the same apparatus makes sense of our speaking about a host of items-Mickey Mouse, unicorns, Martians-that nearly all of us deny exist. It's allowed by what Azzouni shows about the background logic of our ontological debates, as well as the semantics of the language of those debates that we can disagree over the existence of things, like unicorns, without that background logic and semantics forcing ontological commitments onto speakers that they don't have.

Ascriptions of mental states to oneself and others give rise to many interesting logical and semantic problems. Attitude Problems presents an original account of mental state ascriptions that are made using intensional transitive verbs such as "want," "seek," "imagine," and "worship." Forbes offers a theory of how such verbs work that draws on ideas from natural language semantics, philosophy of language, and aesthetics.

Between Saying and Doing aims to reconcile pragmatism (in both its classical American and its Wittgensteinian forms) with analytic philosophy. It investigates the relations between the meaning of linguistic expressions and their use. Giving due weight both to what one has to do in order to count as saying various things and to what one needs to say in order to specify those doings, makes it possible to shed new light on the relations between semantics (the theory of the meanings of utterances and the contents of thoughts) and pragmatics (the theory of the functional relations among meaningful or contentful items). Among the vocabularies whose interrelated use and meaning are considered are: logical, indexical, modal, normative, and intentional vocabulary. As the argument proceeds, new ways of thinking about the classic analytic core programs of empiricism, naturalism, and functionalism are offered, as well as novel insights about the ideas of artificial intelligence, the nature of logic, and intentional relations between subjects and objects.

The philosophy of modality investigates necessity and possibility, and related notions--are they objective features of mind-independent reality? If so, are they irreducible, or can modal facts be explained in other terms? This volume presents new work on modality by established leaders in the field and by up-and-coming philosophers. Between them, the papers address fundamental questions concerning realism and anti-realism about modality, the nature and basis of facts about what is possible and what is necessary, the nature of modal knowledge, modal logic and its relations to necessary existence and to counterfactual reasoning. The general introduction locates the individual contributions in the wider context of the contemporary discussion of the metaphysics and epistemology of modality.

Wittgenstein's philosophical career began in 1911 when he went to Cambridge to work with Russell. He compiled the Notes on Logic two years later as a kind of summary of the work he had done so far. Russell thought that they were "as good as anything that has ever been done in logic," but he had Wittgenstein himself to explain them to him. Without the benefit of Wittgenstein's explanations, most later scholars have preferred to treat the Notes solely as an interpretative aid in understanding the Tractatus (which draws on them for material), rather than as a philosophical work in their own right.
Michael Potter unequivocally demonstrates the philosophical and historical importance of the Notes for the first time. By teasing out the meaning of key passages, he shows how many of the most important insights in the Tractatus they contain. He discusses in detail how Wittgenstein arrived at these insights by thinking through ideas he obtained from Russell and Frege. And he uses a challenging blend of biography and philosophy to illuminate the methods Wittgenstein used in his work.
The book features the complete text of the Notesi in a critical edition, with a detailed discussion of the circumstances in which they were compiled, leading to a new understanding of how they should be read.

This monograph proposes a new (dialogical) way of studying the different forms of correlational inference, known in the Islamic jurisprudence as qiyas. According to the authors' view, qiyas represents an innovative and sophisticated form of dialectical reasoning that not only provides new epistemological insights into legal argumentation in general (including legal reasoning in Common and Civil Law) but also furnishes a fine-grained pattern for parallel reasoning which can be deployed in a wide range of problem-solving contexts and does not seem to reduce to the standard forms of analogical reasoning studied in contemporary philosophy of science and argumentation theory. After an overview of the emergence of qiyas and of the work of al-Shirazi penned by Soufi Youcef, the authors discuss al-Shirazi's classification of correlational inferences of the occasioning factor (qiyas al-'illa). The second part of the volume deliberates on the system of correlational inferences by indication and resemblance (qiyas al-dalala, qiyas al-shabah). The third part develops the main theoretical background of the authors' work, namely, the dialogical approach to Martin-Loef's Constructive Type Theory. The authors present this in a general form and independently of adaptations deployed in parts I and II. Part III also includes an appendix on the relevant notions of Constructive Type Theory, which has been extracted from an overview written by Ansten Klev. The book concludes with some brief remarks on contemporary approaches to analogy in Common and Civil Law and also to parallel reasoning in general.

Gottlob Frege's Grundgesetze der Arithmetik, or Basic Laws of Arithmetic, was intended to be his magnum opus, the book in which he would finally establish his logicist philosophy of arithmetic. But because of the disaster of Russell's Paradox, which undermined Frege's proofs, the more mathematical parts of the book have rarely been read. Richard G. Heck, Jr., aims to change that, and establish it as a neglected masterpiece that must be placed at the center of Frege's philosophy. Part I of Reading Frege's Grundgesetze develops an interpretation of the philosophy of logic that informs Grundgesetze, paying especially close attention to the difficult sections of Frege's book in which he discusses his notorious 'Basic Law V' and attempts to secure its status as a law of logic. Part II examines the mathematical basis of Frege's logicism, explaining and exploring Frege's formal arguments. Heck argues that Frege himself knew that his proofs could be reconstructed so as to avoid Russell's Paradox, and presents Frege's arguments in a way that makes them available to a wide audience. He shows, by example, that careful attention to the structure of Frege's arguments, to what he proved, to how he proved it, and even to what he tried to prove but could not, has much to teach us about Frege's philosophy.

Syllogism is a form of logical argument allowing one to deduce a consistent conclusion based on a pair of premises having a common term. Although Aristotle was the first to conceive and develop this way of reasoning, he left open a lot of conceptual space for further modifications, improvements and systematizations with regards to his original syllogistic theory. From its creation until modern times, syllogism has remained a powerful and compelling device of deduction and argument, used by a variety of figures and assuming a variety of forms throughout history. The Aftermath of Syllogism investigates the key developments in the history of this peculiar pattern of inference, from Avicenna to Hegel. Taking as its focus the longue duree of development between the Middle Ages and the nineteenth century, this book looks at the huge reworking scientific syllogism underwent over the centuries, as some of the finest philosophical minds brought it to an unprecedented height of logical sharpness and sophistication. Bringing together a group of major international experts in the Aristotelian tradition, The Aftermath of Syllogism provides a detailed, up to date and critical evaluation of the history of syllogistic deduction.

With the publication of the present volume, the Handbook of the History of Logic turns its attention to the rise of modern logic. The period covered is 1685-1900, with this volume carving out the territory from Leibniz to Frege. What is striking about this period is the earliness and persistence of what could be called 'the mathematical turn in logic'. Virtually every working logician is aware that, after a centuries-long run, the logic that originated in antiquity came to be displaced by a new approach with a dominantly mathematical character. It is, however, a substantial error to suppose that the mathematization of logic was, in all essentials, Frege's accomplishment or, if not his alone, a development ensuing from the second half of the nineteenth century. The mathematical turn in logic, although given considerable torque by events of the nineteenth century, can with assurance be dated from the final quarter of the seventeenth century in the impressively prescient work of Leibniz. It is true that, in the three hundred year run-up to the Begriffsschrift, one does not see a smoothly continuous evolution of the mathematical turn, but the idea that logic is mathematics, albeit perhaps only the most general part of mathematics, is one that attracted some degree of support throughout the entire period in question. Still, as Alfred North Whitehead once noted, the relationship between mathematics and symbolic logic has been an "uneasy" one, as is the present-day association of mathematics with computing. Some of this unease has a philosophical texture. For example, those who equate mathematics and logic sometimes disagree about the directionality of the purported identity. Frege and Russell made themselves famous by insisting (though for different reasons) that logic was the senior partner. Indeed logicism is the view that mathematics can be re-expressed without relevant loss in a suitably framed symbolic logic. But for a number of thinkers who took an algebraic approach to logic, the dependency relation was reversed, with mathematics in some form emerging as the senior partner. This was the precursor of the modern view that, in its four main precincts (set theory, proof theory, model theory and recursion theory), logic is indeed a branch of pure mathematics. It would be a mistake to leave the impression that the mathematization of logic (or the logicization of mathematics) was the sole concern of the history of logic between 1665 and 1900. There are, in this long interval, aspects of the modern unfolding of logic that bear no stamp of the imperial designs of mathematicians, as the chapters on Kant and Hegcl make clear. Of the two, Hcgel's influence on logic is arguably the greater, serving as a spur to the unfolding of an idealist tradition in logic - a development that will be covered in a further volume, British Logic in the Nineteenth Century.

"An Introduction to the History of Philosophical and Formal Logic" introduces ideas and thinkers central to the development of philosophical and formal logic. From its Aristotelian origins to the present-day arguments, logic is broken down into four main time periods: -Antiquity and the Middle Ages (Aristotle and The Stoics) -The early modern period (Leibniz, Bolzano, Boole) -High modern period (Frege, Peano & Russell and Hilbert)-Early 20th century: (Godel and Tarski) Each new time frame begins with an introductory overview highlighting themes and points of importance. Chapters discuss the significance and reception of influential works and look at historical arguments in the context of contemporary debates. To support independent study, comprehensive lists of primary and secondary reading are included at the end of chapters, along with exercises and discussion questions.By clearly presenting and explaining the changes to logic across the history of philosophy, "An Introduction to the History of Philosophical and Formal Logic" constructs an easy-to-follow narrative. This is an ideal starting point for students looking to understand the historical development of logic.

This comprehensive text shows how various notions of logic can be viewed as notions of universal algebra providing more advanced concepts for those who have an introductory knowledge of algebraic logic, as well as those wishing to delve into more theoretical aspects.

The capacity to represent things to ourselves as possible plays a crucial role both in everyday thinking and in philosophical reasoning; this volume offers much-needed philosophical illumination of conceivability, possibility, and the relations between them.

G. E. Moore famously observed that to assert, 'I went to the pictures last Tuesday but I don't believe that I did' would be 'absurd'. Moore calls it a 'paradox' that this absurdity persists despite the fact that what I say about myself might be true. Over half a century later, such sayings continue to perplex philosophers and other students of language, logic, and cognition. Ludwig Wittgenstein was fascinated by Moore's example, and the absurdity of Moore's saying was intensively discussed in the mid-20th century. Yet the source of the absurdity has remained elusive, and its recalcitrance has led researchers in recent decades to address it with greater care. In this definitive treatment of the problem of Moorean absurdity Green and Williams survey the history and relevance of the paradox and leading approaches to resolving it, and present new essays by leading thinkers in the area. Contributors Jonathan Adler, Bradley Armour-Garb, Jay D. Atlas, Thomas Baldwin, Claudio de Almeida, Andre Gallois, Robert Gordon, Mitchell Green, Alan Hajek, Roy Sorensen, John Williams

What is truth? Michael Lynch defends a bold new answer to this question. Traditional theories of truth hold that truth has only a single uniform nature. All truths are true in the same way. More recent deflationary theories claim that truth has no nature at all; the concept of truth is of no real philosophical importance. In this concise and clearly written book, Lynch argues that we should reject both these extremes and hold that truth is a functional property. To understand truth we must understand what it does, its function in our cognitive economy. Once we understand that, we'll see that this function can be performed in more than one way. And that in turn opens the door to an appealing pluralism: beliefs about the concrete physical world needn't be true in the same way as our thoughts about matters -- like morality -- where the human stain is deepest.

This book offers insight into the nature of meaningful discourse. It presents an argument of great intellectual scope written by an author with more than four decades of experience. Readers will gain a deeper understanding into three theories of the logos: analytic, dialectical, and oceanic. The author first introduces and contrasts these three theories. He then assesses them with respect to their basic parameters: necessity, truth, negation, infinity, as well as their use in mathematics. Analytic Aristotelian logic has traditionally claimed uniqueness, most recently in its Fregean and post-Fregean variants. Dialectical logic was first proposed by Hegel. The account presented here cuts through the dense, often incomprehensible Hegelian text. Oceanic logic was never identified as such, but the author gives numerous examples of its use from the history of philosophy. The final chapter addresses the plurality of the three theories and of how we should deal with it. The author first worked in analytic logic in the 1970s and 1980s, first researched dialectical logic in the 1990s, and discovered oceanic logic in the 2000s. This book represents the culmination of reflections that have lasted an entire scholarly career.

Reference is a central topic in philosophy of language, and has been the main focus of discussion about how language relates to the world. R. M. Sainsbury sets out a new approach to the concept, which promises to bring to an end some long-standing debates in semantic theory. There is a single category of referring expressions, all of which deserve essentially the same kind of semantic treatment. Included in this category are both singular and plural referring expressions ('Aristotle', 'The Pleiades'), complex and non-complex referring expressions ('The President of the USA in 1970', 'Nixon'), and empty and non-empty referring expressions ('Vulcan', 'Neptune'). Referring expressions are to be described semantically by a reference condition, rather than by being associated with a referent. In arguing for these theses, Sainsbury's book promises to end the fruitless oscillation between Millian and descriptivist views. Millian views insist that every name has a referent, and find it hard to give a good account of names which appear not to have referents, or at least are not known to do so, like ones introduced through error ('Vulcan'), ones where it is disputed whether they have a bearer ('Patanjali') and ones used in fiction. Descriptivist theories require that each name be associated with some body of information. These theories fly in the face of the fact names are useful precisely because there is often no overlap of information among speakers and hearers. The alternative position for which the book argues is firmly non-descriptivist, though it also does not require a referent. A much broader view can be taken of which expressions are referring expressions: not just names and pronouns used demonstratively, but also some complex expressions and some anaphoric uses of pronouns. Sainsbury's approach brings reference into line with truth: no one would think that a semantic theory should associate a sentence with a truth value, but it is commonly held that a semantic theory should associate a sentence with a truth condition, a condition which an arbitrary state of the world would have to satisfy in order to make the sentence true. The right analogy is that a semantic theory should associate a referring expression with a reference condition, a condition which an arbitrary object would have to satisfy in order to be the expression's referent. Lucid and accessible, and written with a minimum of technicality, Sainsbury's book also includes a useful historical survey. It will be of interest to those working in logic, mind, and metaphysics as well as essential reading for philosophers of language.

This is a guide to the thought and ideas of Gottlob Frege, one of the most important but also perplexing figures in the history of analytic philosophy. Gottlob Frege is regarded as one of the founders of modern logic and analytic philosophy, indeed as the greatest innovator in logic since Aristotle. His groundbreaking work identified many of the basic conceptions and distinctions that later came to dominate analytic philosophy. The literature on him is legion and ever-growing in complexity, representing a considerable challenge to the non-expert. The details of his logic, which have come into focus in recent research, are particularly difficult to grasp, although they are crucial to the development of his grand project, the reduction of arithmetic to logic, and the associated philosophical innovations. This book offers a lucid and accessible introduction to Frege's logic, taking the reader directly to the core of his philosophy, and ultimately to some of the most pertinent issues in contemporary philosophy of language, logic, mathematics, and the mind. "Continuum's Guides for the Perplexed" are clear, concise and accessible introductions to thinkers, writers and subjects that students and readers can find especially challenging - or indeed downright bewildering. Concentrating specifically on what it is that makes the subject difficult to grasp, these books explain and explore key themes and ideas, guiding the reader towards a thorough understanding of demanding material.

Frege's Theorem collects eleven essays by Richard G Heck, Jr, one of the world's leading authorities on Frege's philosophy. The Theorem is the central contribution of Gottlob Frege's formal work on arithmetic. It tells us that the axioms of arithmetic can be derived, purely logically, from a single principle: the number of these things is the same as the number of those things just in case these can be matched up one-to-one with those. But that principle seems so utterly fundamental to thought about number that it might almost count as a definition of number. If so, Frege's Theorem shows that arithmetic follows, purely logically, from a near definition. As Crispin Wright was the first to make clear, that means that Frege's logicism, long thought dead, might yet be viable.
Heck probes the philosophical significance of the Theorem, using it to launch and then guide a wide-ranging exploration of historical, philosophical, and technical issues in the philosophy of mathematics and logic, and of their connections with metaphysics, epistemology, the philosophy of language and mind, and even developmental psychology. The book begins with an overview that introduces the Theorem and the issues surrounding it, and explores how the essays that follow contribute to our understanding of those issues. There are also new postscripts to five of the essays, which discuss changes of mind, respond to published criticisms, and advance the discussion yet further.