At the centre of the traditional discussion of truth is the question of how truth is defined. Recent research, especially with the development of deflationist accounts of truth, has tended to take truth as an undefined primitive notion governed by axioms, while the liar paradox and cognate paradoxes pose problems for certain seemingly natural axioms for truth. In this book, Volker Halbach examines the most important axiomatizations of truth, explores their properties and shows how the logical results impinge on (...) the philosophical topics related to truth. In particular, he shows that the discussion on topics such as deflationism about truth depends on the solution of the paradoxes. His book is an invaluable survey of the logical background to the philosophical discussion of truth, and will be indispensable reading for any graduate or professional philosopher in theories of truth. (shrink)

Over the past decades, we have witnessed calls for greater transdisciplinary engagement between scientific and societal actors to develop more robust answers to complex societal challenges. Although there seems to be agreement that these approaches might nurture innovations of a new kind, we know little regarding the research practices, their potential, and the limitations. To fill this gap, this article investigates a funding scheme in the area of transdisciplinary sustainability research. It offers a detailed analysis of the imaginaries and expectations (...) on which the funding scheme rests and how researchers actually practice transdisciplinarity within the respective projects. Identifying three ideal typical models of science–society relations at work, attention is paid to how, where, and when societal and scientific arenas get entangled. This article discusses the tensions between classical academic values and efforts to open research to society, the prevailing power structures that make societal participation challenging, the importance of place and technopolitical cultures, and how temporal project structures impede more radical openings to new ways of knowledge production. We finally emphasize that transdisciplinary knowledge production can only become a serious option for addressing societal challenges if broader changes are made to the knowledge regimes in place. (shrink)

Solutions to semantic paradoxes often involve restrictions of classical logic for semantic vocabulary. In the paper we investigate the costs of these restrictions in a model case. In particular, we fix two systems of truth capturing the same conception of truth: of the system KF of Feferman formulated in classical logic, and the system PKF of Halbach and Horsten, formulated in basic De Morgan logic. The classical system is known to be much stronger than the nonclassical one. We assess the (...) reasons for this asymmetry by showing that the truth theoretic principles of PKF cannot be blamed: PKF with induction restricted to non-semantic vocabulary coincides in fact with what the restricted version of KF proves true. (shrink)

To the axioms of Peano arithmetic formulated in a language with an additional unary predicate symbol T we add the rules of necessitation and conecessitation T and axioms stating that T commutes with the logical connectives and quantifiers. By a result of McGee this theory is -inconsistent, but it can be approximated by models obtained by a kind of rule-of-revision semantics. Furthermore we prove that FS is equivalent to a system already studied by Friedman and Sheard and give an analysis (...) of its proof theory. (shrink)

A substitutional account of logical validity for formal first‐order languages is developed and defended against competing accounts such as the model‐theoretic definition of validity. Roughly, a substitution instance of a sentence is defined as the result of uniformly substituting nonlogical expressions in the sentence with expressions of the same grammatical category and possibly relativizing quantifiers. In particular, predicate symbols can be replaced with formulae possibly containing additional free variables. A sentence is defined to be logically true iff all its substitution (...) instances are satisfied by all variable assignments. Logical consequence is defined analogously. Satisfaction is taken to be a primitive notion and axiomatized.For every set‐theoretic model in the sense of model theory there exists a corresponding substitutional interpretation in a sense to be specified. Conversely, however, there are substitutional interpretations – in particular the ‘intended’ interpretation – that lack a model‐theoretic counterpart. The substitutional definition of logical validity overcomes the weaknesses of more restrictive accounts of substitutional validity; unlike model‐theoretic logical consequence, the substitutional notion is trivially and provably truth preserving. In Kreisel's squeezing argument the formal notion of substitutional validity naturally slots into the place of intuitive validity. (shrink)

Wittgenstein’s Whewell’s Court Lectures contains previously unpublished notes from lectures given by Ludwig Wittgenstein between 1938 and 1941. The volume offers new insight into the development of Wittgenstein’s thought and includes some of the finest examples of Wittgenstein’s lectures in regard to both content and reliability.

We investigate axiomatizations of Kripke's theory of truth based on the Strong Kleene evaluation scheme for treating sentences lacking a truth value. Feferman's axiomatization KF formulated in classical logic is an indirect approach, because it is not sound with respect to Kripke's semantics in the straightforward sense: only the sentences that can be proved to be true in KF are valid in Kripke's partial models. Reinhardt proposed to focus just on the sentences that can be proved to be true in (...) KF and conjectured that the detour through classical logic in KF is dispensable. We refute Reinhardt's Conjecture, and provide a direct axiomatization PKF of Kripke's theory in partial logic. We argue that any natural axiomatization of Kripke's theory in Strong Kleene logic has the same proof-theoretic strength as PKF, namely the strength of the system RA< ωω ramified analysis or a system of Tarskian ramified truth up to ωω. Thus any such axiomatization is much weaker than Feferman's axiomatization KF in classical logic, which is equivalent to the system RA<ε₀ of ramified analysis up to ε₀. (shrink)

Logical consequence in first-order predicate logic is defined substitutionally in set theory augmented with a primitive satisfaction predicate: an argument is defined to be logically valid if and only if there is no substitution instance with true premises and a false conclusion. Substitution instances are permitted to contain parameters. Variants of this definition of logical consequence are given: logical validity can be defined with or without identity as a logical constant, and quantifiers can be relativized in substitution instances or not. (...) It is shown that the resulting notions of logical consequence are extensionally equivalent to versions of first-order provability and model-theoretic consequence. Every model-theoretic interpretation has a substitutional counterpart, but not vice versa. In particular, in contrast to the model-theoretic account, there is a trivial intended interpretation on the substitutional account, namely, the homophonic interpretation that does not substitute anything. Applications to free logic, and theories and languages other than set theory are sketched. (shrink)

Epiphenomenalism has been criticized with several objections. It has been argued that epiphenomenalism is incompatible with the alleged causal relevance of mental states, and that it renders knowledge of our own conscious states impossible. In this article, it is demonstrated that qualia-epiphenomenalism follows from some well- founded assumptions, and that it meets the cited objections. Though not free from difficulties, it is at least superior to its main competitors, namely, physicalism and interactionism.

Definitional and axiomatic theories of truth -- Objects of truth -- Tarski -- Truth and set theory -- Technical preliminaries -- Comparing axiomatic theories of truth -- Disquotation -- Classical compositional truth -- Hierarchies -- Typed and type-free theories of truth -- Reasons against typing -- Axioms and rules -- Axioms for type-free truth -- Classical symmetric truth -- Kripke-Feferman -- Axiomatizing Kripke's theory in partial logic -- Grounded truth -- Alternative evaluation schemata -- Disquotation -- Classical logic -- Deflationism (...) -- Reflection -- Ontological reduction -- Applying theories of truth. (shrink)

We prove Yablo’s paradox without the diagonal lemma or the recursion theorem. Only a disquotation schema and axioms for a serial and transitive ordering are used in the proof. The consequences for the discussion on whether Yablo’s paradox is circular or involves self-reference are evaluated.

The Logic Manual is a clear and concise introduction to logic for beginning philosophy students.

While classical temporal logics lose track of a state as soon as a temporal operator is applied, several branching-time logics able to repeatedly refer to a state have been introduced in the literature. We study such logics by introducing a new formalism, hybrid branching-time logics, subsuming the other approaches and making the ability to refer to a state more explicit by assigning a name to it. We analyze the expressive power of hybrid branching-time logics and the complexity of their satisfiability (...) problem. As main result, the satisfiability problem for the hybrid versions of several branching-time logics is proved to be 2EXPTIME -complete. To prove the upper bound, the automata-theoretic approach to branching-time logics is extended to hybrid logics. As a result of independent interest, the nonemptiness problem for alternating one-pebble Büchi tree automata is shown to be 2EXPTIME -complete. A common property of the logics studied is that they refer to only one state. This restriction is crucial: The ability to refer to more than one state causes a nonelementary blow-up in complexity. In particular, we prove that satisfiability for NCTL * has nonelementary complexity. (shrink)

This article suggests reading Theodor Adorno not as a notoriously pessimistic sociologist but as a committed public educator. Partly drawing on still unpublished transcripts of lectures, public talks and radio broadcasts from the 1950s and ’60s, the article offers an account of Adorno’s concept and practice of a ‘democratic pedagogy’. The key question is how we should understand the difference between Adorno the social philosopher, on the one hand, and Adorno the educator, on the other. It is argued that Adorno’s (...) pedagogical interventions are not a footnote to his social theory, but a key to understanding his entire oeuvre. (shrink)

On the one hand, the concept of truth is a major research subject in analytic philosophy. On the other hand, mathematical logicians have developed sophisticated logical theories of truth and the paradoxes. Recent developments in logical theories of the semantical paradoxes are highly relevant for philosophical research on the notion of truth. And conversely, philosophical guidance is necessary for the development of logical theories of truth and the paradoxes. From this perspective, this volume intends to reflect and promote deeper interaction (...) and collaboration between philosophers and logicians investigating the concept of truth than has existed so far.Aside from an extended introductory overview of recent work in the theory of truth, the volume consists of articles by leading philosophers and logicians on subjects and debates that are situated on the interface between logical and philosophical theories of truth. The volume is intended for graduate students in philosophy and in logic who want an introduction to contemporary research in this area, as well as for professional philosophers and logicians. (shrink)

Theoretical Laws and Normative Rules: Kant and Bolzano's Views on Logic'"1" Anita Von Duhn, Genf Does logic instruct us how to think correctly? ...

The paper deals with the regressive analytical method understood as "the way backward". In the first section the paper gives a historical survey concentrating on three paradigmatic examples: Pappus's definition of analysis and synthesis, the definition of method to be found in the so_called "Logic of Port Royal", and David Hilbert's definition of the axiomatic method as a procedure for setting up axiomatic systems. In the second section the scepticism of traditional philosophy of science concerning the regressive method is reflected.

This article critically engages a recent essay Jeffrey Alexander has published on ‘societalization’, whose conceptualization it finds problematic; first, because in contrast to the impression conveyed by the essay, the term itself is anything but new (as shown in a summary of six theories of societalization which precede Alexander’s by decades, in two cases, by more than a century), and, second, because the way Alexander employs the term is highly aporetic, while also being emblematic of much deeper problems that afflict (...) the whole discipline. Following a reconstruction of the term’s morphology and the transmutations it underwent during its gradual incorporation into the English language, the article identifies an undertheorized concept of society as the root cause behind the difficulties into which Alexander maneuvers himself. It concludes with a brief sketch of an alternative that can contribute to overcoming these difficulties. (shrink)

This chapter discusses the complex conditions for the emergence of 19th-century symbolic logic. The main scope will be on the mathematical motives leading to the interest in logic; the philosophical context will be dealt with only in passing. The main object of study will be the algebra of logic in its British and German versions. Special emphasis will be laid on the systems of George Boole and above all of his German follower Ernst Schröder.

If □ is conceived as an operator, i.e., an expression that gives applied to a formula another formula, the expressive power of the language is severely restricted when compared to a language where □ is conceived as a predicate, i.e., an expression that yields a formula if it is applied to a term. This consideration favours the predicate approach. The predicate view, however, is threatened mainly by two problems: Some obvious predicate systems are inconsistent, and possible-worlds semantics for predicates of (...) sentences has not been developed very far. By introducing possible-worlds semantics for the language of arithmetic plus the unary predicate □, we tackle both problems. Given a frame (W, R) consisting of a set W of worlds and a binary relation R on W, we investigate whether we can interpret □ at every world in such a way that □ $\ulcorner A \ulcorner$ holds at a world ᵆ ∊ W if and only if A holds at every world $\upsilon$ ∊ W such that ᵆR $\upsilon$ . The arithmetical vocabulary is interpreted by the standard model at every world. Several 'paradoxes' (like Montague's Theorem, Gödel's Second Incompleteness Theorem, McGee's Theorem on the ω-inconsistency of certain truth theories, etc.) show that many frames, e.g., reflexive frames, do not allow for such an interpretation. We present sufficient and necessary conditions for the existence of a suitable interpretation of □ at any world. Sound and complete semi-formal systems, corresponding to the modal systems K and K4, for the class of all possible-worlds models for predicates and all transitive possible-worlds models are presented. We apply our account also to nonstandard models of arithmetic and other languages than the language of arithmetic. (shrink)

Against competing political theories of the integration of immigrants, we propose to reframe the relationship between the populations of host countries and arriving refugees in terms of a neo-Maussian theory of gift exchange. Using the example of the European refugee crisis of 2015 and the welcoming attitude of significant parts of German civil society, we argue that this particular situation should be understood as epitomizing the trend toward internal transnationalism. Increasingly, the “international” is becoming part and parcel of the “domestic” (...) sphere. Since Marcel Mauss was concerned with the question of how separate, culturally different communities can establish ties of solidarity and cooperation between each other, we use his work to answer key questions about the relations between international refugees and native citizens in their home countries: What are the expectations underlying gift-giving in the context of welcoming refugees? Should refugees feel obliged to repay the arrival gifts? How sh... (shrink)

Disquotational theories of truth, that is, theories of truth based on the T-sentences or similar equivalences as axioms are often thought to be deductively weak. This view is correct if the truth predicate is allowed to apply only to sentences not containing the truth predicate. By taking a slightly more liberal approach toward the paradoxes, I obtain a disquotational theory of truth that is proof theoretically as strong as compositional theories such as the Kripket probe the compositional axioms.

This first of two volumes brings together invited papers of the 32nd International Wittgenstein Symposium (Kirchberg/W. (Austria), 2009). The relation between language and the world was undoubtedly one if not the central issue in Wittgenstein's whole philosophical oeuvre. His one hundred and twentieth birthday provided an occasion for foregrounding this aspect of his work. A special workshop was dedicated to new aspects of Wittgenstein's Nachlass. In this volume Frank Cioffi, Peter Hacker, Ian Hacking, Roy Harris, Lars Hertzberg, Jaakko Hintikka, Marie (...) McGinn, Danièle Moyal-Sharrock, Hans Sluga among others provide substantial contributions on various aspects of Wittgenstein's writings such as the philosophy of mathematics, the problem of rule following or the relation between meaning and use. (shrink)

In many fields of contemporary thought and scholarship, the classical construct of a clean division between “emotion” and “reason” has been revised. As a result, politics is no longer seen as a sphere in need of protection against the dark forces of emotion that might creep in where they do not belong. Against the backdrop of this conceptual shift the article examines the theme of emotion in the political thought of Max Weber and Hannah Arendt. The aim is to gauge (...) the extent to which these thinkers can be read as having prepared the ground for a reassessment of the role of emotion in public life that moves beyond the classical European dichotomy of reason vs. passion. Two claims are being made. Both thinkers were still immersed in a conceptual world in which emotions were irrational, disruptive of appropriate ways of reasoning and as such closely linked to the dark powers of the masses. Yet both also held subtler positions on the relationship between reason, emotion, and democracy, and these positions are less well understood. (shrink)

This article introduces Turing’s idea of a “paper machine” to identify and understand one important mode of clinical research in the modern hospital, how that research worked, and how office technology and industrialized labor shaped and helped drive it. The unusually rich archives of Berlin psychiatry allow detailed reconstruction of the making of the new diagnostic category “hyperkinetic syndrome” in the 1920s. From the generating of data to the processing of information to the visualizing of the nature and course of (...) the new syndrome in the lives of more than sixty patients, this case study shows how clinical research could be based on the apparatus of the clerks’ room (folders, registers, inventories, and the dispatch of documents), office technologies (new filing systems, preprinted forms, and duplicating machines), and the principles and paper practices of the division and rationalization of labor (charts organizing worktime in complex organizations). The result is an important example of clinical research embedded in the broader history of office technology, industrial labor, and the modern hospital. (shrink)

The uniform reflection principle for the theory of uniform T-sentences is added to PA. The resulting system is justified on the basis of a disquotationalist theory of truth where the provability predicate is conceived as a special kind of analyticity. The system is equivalent to the system ACA of arithmetical comprehension. If the truth predicate is also allowed to occur in the sentences that are inserted in the T-sentences, yet not in the scope of negation, the system with the reflection (...) schema for these T-sentences assumes the strength of the Kripke-Feferman theory KF, and thus of ramified analysis up to $\varepsilon_0$. (shrink)

The purpose of this article is to explore the potential contribution of Axel Honneth's critical theory of recognition to empirical and normative debates on global justice. I first present, very briefly, an overview of recent theories of global distributive justice. I argue that theorists of distributive justice do not pay enough attention to sources of self-respect and conditions for identity formation, and that they are blind toward the danger of harming people's sense of self even by well-intentioned redistributive policies. Honneth's (...) theory suffers from complementary shortcomings; it is anti-technocratic but largely oblivious to the global nature of many contemporary justice claims. Given this situation, I seek to broaden the theory's scope by outlining transnational extensions of the recognition principles of love, rights and solidarity identified by Honneth. In conclusion, I show how utilizing a broadened conceptualization of the struggle for recognition allows us to better understand the changing logic of justice-oriented foreign policies. (shrink)