the demise of the logical positivism programme. The answers given to these qu- tions have deepened the already existing gap between philosophy and the history and practice of science. While the positivists argued for a spontaneous, steady and continuous growth of scientific knowledge the post-positivists make a strong case for a fundamental discontinuity in the development of science which can only be explained by extrascientific factors. The political, social and cultural environment, the argument goes on, determine both the questions and the terms in which they should be answered. Accordingly, the sociological and historical interpretation - volves in fact two kinds of discontinuity which are closely related: the discontinuity of science as such and the discontinuity of the more inclusive political and social context of its development. More precisely it explains the discontinuity of the former by the discontinuity of the latter subordinating in effect the history of science to the wider political and social history. The underlying idea is that each historical and - cial context generates scientific and philosophical questions of its own. From this point of view the question surrounding the nature of knowledge and its development are entirely new topics typical of the twentieth-century social context reflecting both the level and the scale of the development of science.

This volume clusters together issues centered upon the variety of types of intensional semantics. Consisting of 10 contributions, the volume is based on papers presented at the Trends in Logic 2019 conference. The various chapters introduce readers to the topic, or apply new types of logical semantics to elucidate subtleties of logical systems and natural language semantics. The book introduces hyperintentional systems that aim at solving some open philosophical problems. Specifically, the first three studies focus on relating semantics, while the following ones discuss fundamental issues related to hyper-intensional semantics or develop hyper-intensional frameworks to address issues in modal, epistemic, deontic and action logic. Authors in this volume present original results on logical systems but also extend beyond this by offering philosophical considerations on the topic as well. This volume will appeal to students and researchers in the field of logic.

Things are particulars and their qualities are universals, but do universals have an existence distinct from the particular things describable by those terms? And what must be their nature if they do? This book provides a careful and assured survey of the central issues of debate surrounding universals, in particular those issues that have been a crucial part of the emergence of contemporary analytic ontology. The book begins with a taxonomy of extreme nominalist, moderate nominalist, and realist positions on properties, and outlines the way each handles the phenomena of predication, resemblance, and abstract reference. The debate about properties and philosophical naturalism is also examined. Different forms of extreme nominalism, moderate nominalism, and minimalist realism are critiqued. Later chapters defend a traditional realist view of universals and examine the objections to realism from various infinite regresses, the difficulties in stating identity conditions for properties, and problems with realist accounts of knowledge of abstract objects. In addition, the debate between Platonists and Aristotelians is examined alongside a discussion of the relationship between properties and an adequate theory of existence. The book's final chapter explores the problem of individuating particulars. The book makes accessible a difficult topic without blunting the sophistication of argument required by a more advanced readership.

Mathematician and popular science author Eugenia Cheng is on a mission to show you that mathematics can be flexible, creative, and visual. This joyful journey through the world of abstract mathematics into category theory will demystify mathematical thought processes and help you develop your own thinking, with no formal mathematical background needed. The book brings abstract mathematical ideas down to earth using examples of social justice, current events, and everyday life - from privilege to COVID-19 to driving routes. The journey begins with the ideas and workings of abstract mathematics, after which you will gently climb toward more technical material, learning everything needed to understand category theory, and then key concepts in category theory like natural transformations, duality, and even a glimpse of ongoing research in higher-dimensional category theory. For fans of How to Bake Pi, this will help you dig deeper into mathematical concepts and build your mathematical background.

Philosophy in the medieval Latin West before 1200 is often thought to have been dominated by Platonism. The articles in this volume question this view, by cataloguing, describing and investigating the tradition of Aristotelian logic during this period, examining its influence on authors usually placed within the Aristotelian tradition (Eriugena, Anselm, Gilbert of Poitiers), and also looking at some of the characteristics of early medieval Platonism. Abelard, the most brilliant logician of the age, is the main subject of three articles, and the book concludes with two more general discussions about how and why medieval philosophy should be studied.

The book offers a reflection on the nature, scope, and limits of knowledge that have been at the focus of the author's work over decades. The essays collected in this volume expound and extend these efforts in exploring the outer fringes of understanding: the outer boundaries of conceivability, the limits of cognition, and the ramifications of ineffability and paradox. They join in exploring the lay of the land at the boundaries of knowledge. The first chapters address basic facts regarding the conceptualization of knowledge. This is followed by a study on how to deal with problems relating to the affirmation and considerations of truth. The final chapters scrutinize the limits of demonstration and the inherent impossibility of realizing an ideal systematization of our knowledge of totalities. The book affords novel perspectives regarding the thought of a widely appreciated philosopher. It is an original work aimed for readers interested in the theory of knowledge and philosophy of cognition.

Today's instantaneous and ever-present news stream frequently presents a sensationalized or otherwise distorted view of the world, demanding constant critical engagement on the part of everyday citizens. The Critical Thinker's Guide to Bias, Lies, and Politics in the News reveals the power of critical thinking to make sense of overwhelming and often subjective media by detecting ideology, slant, and spin at work. Building off the Richard Paul and Linda Elder framework for critical thinking, Elder focuses on the internal logic of the news as well as societal influences on the media while illustrating essential elements of trustworthy journalism. With up-to-date discussions of social media, digital journalism, and political maneuvering inside and outside the fourth estate, Fact or Fake is an essential handbook for those who want to stay informed but not influenced by our modern news reporting systems.

An Invitation to Formal Reasoning introduces the discipline of formal logic by means of a powerful new system formulated by Fred Sommers. This system, term logic, is different in a number of ways from the standard system employed in modern logic; most striking is its greater simplicity and naturalness. Based on a radically different theory of logical syntax than the one Frege used when initiating modern mathematical logic in the 19th Century, term logic borrows insights from Aristotle's syllogistic, Scholastic logicians, Leibniz, and the 19th century British algebraists. Term logic takes its syntax directly from natural language, construing statements as combinations of pairs of terms, where complex terms are taken to have the same syntax as statements. Whereas standard logic requires extensive 'translation' from natural language to symbolic language, term logic requires only 'transcription' into the symbolic language. Its naturalness is the result of its ability to stay close to the forms of sentences usually found in every day discourse. Written by the founders of the term logic approach, An Invitation to Formal Reasoning is a unique introduction and exploration of this new system, offering numerous exercises and examples throughout the text. Summarising the standard system of mathematical logic to set term logic in context, and showing how the two systems compare, this book presents an alternative approach to standard modern logic for those studying formal logic, philosophy of language or computer theory. Fred Sommers is Professor Emeritus, Brandeis University, USA; George Englebretsen is Professor of Philosophy, Bishop's University, Canada.

This book deals with the main proponents of the causal and descriptivist reference theories on natural kind terms. The two main types of contemporary reference theories on natural kind terms are the causal and the descriptivist theories. The author analyzes the main versions of these two types of theories and claims that the differences between them are not as great as it is usually assumed. He alleges that the ostensive reference fixing and reference borrowing theories should be descriptive-causal, and he also adduces that the relation of kind-identity depends on the views on kind-identity and thus involves descriptive elements. This book is an important contribution to the debate on reference in contemporary philosophy of language and linguistics.

The Law of Non-Contradiction -- that no contradiction can be true -- has been a seemingly unassailable dogma since the work of Aristotle, in Book G of the Metaphysics. It is an assumption challenged from a variety of angles in this collection of original papers. Twenty-three of the world's leading experts investigate the "law," considering arguments for and against it and discussing methodological issues that arise whenever we question the legitimacy of logical principles. The result is a balanced inquiry into a venerable principle of logic, one that raises questions at the very center of logic itself.
The aim of this volume is to present a comprehensive debate about the Law of Non-Contradiction, from discussions as to how the law is to be understood, to reasons for accepting or re-thinking the law, and to issues that raise challenges to the law, such as the Liar Paradox, and a "dialetheic" resolution of that paradox. The editors contribute an introduction which surveys the issues and serves to frame the debate, and a useful bibliography offering a guide to further reading.
This volume will be of interest to anyone working on philosophical logic, and to anyone who has ever wondered about the status of logical laws and about how one might proceed to mount arguments for or against them.

This book is a consideration of Hegel's view on logic and basic logical concepts such as truth, form, validity, and contradiction, and aims to assess this view's relevance for contemporary philosophical logic. The literature on Hegel's logic is fairly rich. The attention to contemporary philosophical logic places the present research closer to those works interested in the link between Hegel's thought and analytical philosophy (Stekeler-Weithofer 1992 and 2019, Berto 2005, Rockmore 2005, Redding 2007, Nuzzo 2010 (ed.), Koch 2014, Brandom 2014, 1-15, Pippin 2016, Moyar 2017, Quante & Mooren 2018 among others). In this context, one particularity of this book consists in focusing on something that has been generally underrated in the literature: the idea that, for Hegel as well as for Aristotle and many other authors (including Frege), logic is the study of the forms of truth, i.e. the forms that our thought can (or ought to) assume in searching for truth. In this light, Hegel's thinking about logic is a fundamental reference point for anyone interested in a philosophical foundation of logic.

In Ignes Fatui, Charles Thomas Taylor examines various misapprehensions and misconceptions that interfere with clear rational thought. The title of the book, a loanword from Medieval Latin, means "foolish fires"-lights that occasionally appear in the nighttime over marshy ground and are frequently attributable to the combination of gases emitted by decomposed organic matter. The term is sometimes used in modern times to suggest deceptive thoughts, goals, or hopes. The first four chapters of Ignes Fatui consider various common illusions that interfere with sound objective thought in society. The fifth and final chapter considers the illusions that prevent and consequently forestall any form of effectual subjective thinking in personal life. The primary objective of the book is to attempt to improve rational thought and thereby reverse the general decline of faith in the power of reason today.

This volume brings together a group of philosophically oriented logicians and logic-minded philosophers, mainly from Asia, to address a variety of logical and philosophical topics, such as modal logic and related directions (e.g. temporal logic, epistemic logic, deontic logic, logic of conditionals, and modal proof theory), theory of truth, paradoxes, intentionality, and social networks. New approaches are also proposed, such as extended modal logic with planarity of graphs, extended branching time temporal logic with conditional operators, and a relational treatment of language and logical systems, to name but a few.Given the variety of topics and issues discussed here, the book will appeal to readers from a broad range of disciplines, from mathematical/philosophical logic, computing science, cognitive science and artificial intelligence, to linguistics, game theory and beyond.

Assuming no previous study in logic, this informal yet rigorous text covers the material of a standard undergraduate first course in mathematical logic, using natural deduction and leading up to the completeness theorem for first-order logic. At each stage of the text, the reader is given an intuition based on standard mathematical practice, which is subsequently developed with clean formal mathematics. Alongside the practical examples, readers learn what can and can't be calculated; for example the correctness of a derivation proving a given sequent can be tested mechanically, but there is no general mechanical test for the existence of a derivation proving the given sequent. The undecidability results are proved rigorously in an optional final chapter, assuming Matiyasevich's theorem characterising the computably enumerable relations. Rigorous proofs of the adequacy and completeness proofs of the relevant logics are provided, with careful attention to the languages involved. Optional sections discuss the classification of mathematical structures by first-order theories; the required theory of cardinality is developed from scratch. Throughout the book there are notes on historical aspects of the material, and connections with linguistics and computer science, and the discussion of syntax and semantics is influenced by modern linguistic approaches. Two basic themes in recent cognitive science studies of actual human reasoning are also introduced. Including extensive exercises and selected solutions, this text is ideal for students in Logic, Mathematics, Philosophy, and Computer Science.

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.

This book on proof theory centers around the legacy of Kurt Schutte and its current impact on the subject. Schutte was the last doctoral student of David Hilbert who was the first to see that proofs can be viewed as structured mathematical objects amenable to investigation by mathematical methods (metamathematics). Schutte inaugurated the important paradigm shift from finite proofs to infinite proofs and developed the mathematical tools for their analysis. Infinitary proof theory flourished in his hands in the 1960s, culminating in the famous bound 0 for the limit of predicative mathematics (a fame shared with Feferman). Later his interests shifted to developing infinite proof calculi for impredicative theories. Schutte had a keen interest in advancing ordinal analysis to ever stronger theories and was still working on some of the strongest systems in his eighties. The articles in this volume from leading experts close to his research, show the enduring influence of his work in modern proof theory. They range from eye witness accounts of his scientific life to developments at the current research frontier, including papers by Schutte himself that have never been published before.

In just the last twenty years there has arisen a strong interest, especially among teachers of logic at the universities, in teaching techniques of applied logical reasoning and critical thinking. Many universities are now stressing these skills at an introductory level, and to meet the need, informal logic has begun to form and grow as a discipline in its own right. Like all subjects, it helps us to understand it if we can situate it in a context of historical development. This collection of essays provides the readings required to understand the development of a subject whose historical origins have been so far little studied. Many of the chapters are written by scholars in philosophy and speech communication who are themselves leading contributors to the subject, and their contemporary views throw light on how these earlier writers have influenced their thinking. This dimension gives an added interest to the essays, and indicates the way informal logic is currently evolving and seeking out its ancient historical origins.

The International research Library of Philosophy collects in book form a wide range of important and influential essays in philosophy, drawn predominantly from English-language journals. Each volume in the library deals with a field of enquiry which has received significant attention in philosophy in the last 25 years and is edited by a philosopher noted in that field.

In three comprehensive volumes, Logic of the Future presents a full panorama of Charles S. Peirce's most important late writings. Among the most influential American thinkers, Peirce took his existential graphs to be a significant contribution to human thought. The manuscripts from 1895-1913, with many of them being published here for the first time, testify to the richness and open-endedness of his theory of logic and its applications. They also invite us to reconsider our ordinary conceptions of reasoning as well as the conventional stories concerning the evolution of modern logic. This first volume of Logic of the Future is on the historical development, theory and application of Peirce's graphical method and diagrammatic reasoning. It also illustrates the abundant further developments and applications Peirce envisaged existential graphs to have on the analysis of mathematics, language, meaning and mind.

The Collected Works of John Stuart Mill took thirty years to complete and is acknowledged as the definitive edition of J.S. Mill and as one of the finest works editions ever completed. Mill's contributions to philosophy, economics, and history, and in the roles of scholar, politician and journalist can hardly be overstated and this edition remains the only reliable version of the full range of Mill's writings. Each volume contains extensive notes, a new introduction and an index. Many of the volumes have been unavailable for some time, but the Works are now again available, both as a complete set and as individual volumes.

The Collected Works of John Stuart Mill took thirty years to complete and is acknowledged as the definitive edition of J.S. Mill and as one of the finest works editions ever completed. Mill's contributions to philosophy, economics, and history, and in the roles of scholar, politician and journalist can hardly be overstated and this edition remains the only reliable version of the full range of Mill's writings. Each volume contains extensive notes, a new introduction and an index. Many of the volumes have been unavailable for some time, but the Works are now again available, both as a complete set and as individual volumes.

This work represents an attempt to show that standard systems of deontic logic (taken as attempts to codify normal deontic reasoning) run into a number of difficulties. It also presents a new system of deontic logic and argues that it is free from the shortcomings of standard systems.

We all reason about what we ought to do, what should be, and what is permissible, but neither Standard Deontic Logic (SDL) nor its more recent variants adequately represent the principles of our deontic reasoning. In this groundbreaking new work, author James Forrester first explores the shortcomings of standard deontic systems, and concludes that we need a new type of deontic logic; in the second part of the book, he presents a new deontic logic and semantics that fit our deontic reasoning better than standard systems. Finally, in a third section, Forrester sketches some original implications of his new deontic logic for practical reasoning. This book will be of interest to all philosophers, especially those with an interest in questions of moral and practical reasoning.

A new direction in philosophy
Between 1920 and 1940 logical empiricism reset the direction of philosophy of science and much of the rest of Anglo-American philosophy. It began as a relatively organized movement centered on the Vienna Circle, and like-minded philosophers elsewhere, especially in Berlin. As Europe drifted into the Nazi era, several important figures, especially Carnap and Neurath, also found common ground in their liberal politics and radical social agenda. Together, the logical empiricists set out to reform traditional philosophy with a new set of doctrines more firmly grounded in logic and science.
Criticism and decline
Because of Nazi persecution, most of the European adherents of logical empiricism moved to the United States in the late 1930s. During the 1940s, many of their most cherished tenets became targets of criticism from outsiders as well as from within their own ranks. Philosophers of science in the late 1950s and 1960s rejected logical empiricism and, starting in the 1970s, presented such alternative programs such as scientific realism with evolutionary epistemology.
A resurgence of interest
During the early 1980s, philosophers and historians of philosophy began to study logical empiricism as an important movement. Unlike their predecessors in the 1960s-for whom the debate over logical empiricism now seems to have been largely motivated by professional politics-these philosopher no longer have to take positions for or against logical empiricism. The result has been a more balanced view of that movement, its achievements, its failures, and its influence.
Hard-to-find core writings now available
This collection makes available aselection of the most influential and representative writings of the logical empiricists, important contemporary criticisms of their doctrines, their responses, as well as the recent reappraisals. Introductions to each volume examine the articles in historical context and provide important background information that is vital to a full understanding of the issues discussed. They outline prevalent trends, identifying leading figures and summarize their positions and reasoning, as well as those of opposing thinkers.