Dirk Greimann

The syntax of Frege's scientific language is commonly taken to be characterized by two oddities: the representation of the intended illocutionary role of sentences by a special sign, the judgement-stroke, and the treatment of sentences as a species of singular terms. In this paper, an alternative view is defended. The main theses are: the syntax of Frege's scientific language aims at an explication of the logical form of judgements; the judgement-stroke is, therefore, a truth-operator, not a pragmatic operator; in Frege's first system, '⊦ Δ' expresses that the circumstance Δ is a fact, and in his second system that the truth-value - Δ is the True; in both systems, the judgement-stroke is construed as a sign sui generis, not as a genuine predicate; its counterpart in natural language is the syntactic "form of assertoric sentences", not the truth-predicate; neither in Frege's first nor in his second system sentences are treated as singular terms.

Quine has persuasively shown that the empiricist "dogma of reductionism", which is the belief that each meaningfiil statement of science can be reduced to statements about immediate sense experience, must be abandoned. However, Quine's methodology of ontology seems to incorporate an analogous physicalistic dogma according to which the identity conditions of each scientifically respectable sort of abstract objects can be reduced to the identity conditions of physical objects. This paper aims to show that the latter dogma must be abandoned, too. In section 1, the reductionist methodology underlying Quine's prescript "No Entity without Identity" is reconstructed in detail. In section 2 and 3, this methodology is criticized on the ground that Quine's individuation of sets offendsagainst the reductive Criteria of adequacy for individuations that are presupposed by his criticism of the ontological recognition of intensional objects. Finally, in section 4 an alternative holistic conception of individuation is outlined.

According to Frege, the introduction of a new sort of abstract object is methodologically sound only if its identity conditions have been satisfactorily explained. Ironically, this ontological restriction has come to be known by Quine's criticism of Frege's intensional semantics, as the precept "No entity without identity." The aim of the paper is to reconstruct Frege's methodology of the introduction of abstract objects in detail, and to defend it against the more restrictive methodology underlying Quine's criticism of the recognition of intensional objects. The main thesis is that Quine's criterion of non-circularity for the satisfactory individuation of abstract objects must be rejected

The Idea behind Tarski's Definition of Truth. In Tarski's presentations of his truth-definition, the steps of the construction are not sufficiently explained. It is not clear, on what general strategy the construction is based, what the fundamental ideas are, how some crucial steps work, and especially how the transition from the definition of satisfaction to the definition of truth should be understood. The paper shows that the account given in the model-theoretic literature, which is supported by Tarski's lemmata A and B, is unsatisfactory, because Tarski's notion of truth can't be interpreted as ‘truth independent of the assignment of values to the variables’. Moreover, a satisfactory account of all the crucial steps is given.

The purpose of this paper is to reconstruct Frege’s argument against the relativity of truth contained in his posthumous writing Logic from 1897. Two points are made. The first is that the argument is a performative version of the common objection that truth relativism is incoherent: it is designed to show that the assertion of the relativity of truth involves a performative incoherence, because the absoluteness of truth is a success condition for making assertions. From a modern point of view, the central premise of the argument, that the successful making of assertions depends on the absoluteness of truth, is highly doubtful. The second point is that this premise can be made plausible within the framework of Frege’s conception of truth and assertion: it can be derived from his thesis that, in order to put something forward as true, we do not need the word ‘true’, but only the assertoric force.

Frege hat in seinen Schriften zu den philosophischen Grundlagen der Logik eine eigenwillige Konzeption der Wahrheit skizziert, der zufolge das Wahre und das Falsche keine Eigenschaften von Sätzen oder Gedanken sind, sondern Gegenstände, die von Sätzen bezeichnet werden. In dem vorliegenden Sammelband werden zentrale Komponenten dieser Konzeption näher beleuchtet: die Thesen der Undefinierbarkeit der Wahrheit und der Redundanz des Wortes „wahr“, die Auffassung der Wahrheitswerte als Gegenstände, das so genannte slingshot-Argument, die Konzeption der Tatsachen als wahre Gedanken und die Bestimmung der logischen Gesetze als Gesetze des Wahrseins. Mit Beiträgen von Joachim Bromand, Gottfried Gabriel, Martin Grajner, Dirk Greimann, Andreas Kemmerling, Ulrike Kleemeier, Michael Kober, Verena Mayer, Uwe Meixner, Marco Ruffino, Richard Schantz, Hans Sluga und Christian Thiel.

This paper aims to determine what kind of problem Frege's famous “Julius Caesar problem” is. whether it is to be understood as the metaphysical problem of determining what kind of things abstract objects like numbers or value‐courses are, or as the epistemological problem of providing a means of recognizing these objects as the same again, or as the logical problem of providing abstract sortal concepts with a sharp delimitation in order to fulfill the law of excluded middle, or as the semantic problem of fixing the referents of the corresponding abstract singular terms. It is argued that, for Frege, the Caesar problem is a bundle of related problems of which the semantic problem is the most basic one

Quine has persuasively shown that the empiricist "dogma of reductionism", which is the belief that each meaningfiil statement of science can be reduced to statements about immediate sense experience, must be abandoned. However, Quine's methodology of ontology seems to incorporate an analogous physicalistic dogma according to which the identity conditions of each scientifically respectable sort of abstract objects can be reduced to the identity conditions of physical objects. This paper aims to show that the latter dogma must be abandoned, too. In section 1, the reductionist methodology underlying Quine's prescript "No Entity without Identity" is reconstructed in detail. In section 2 and 3, this methodology is criticized on the ground that Quine's individuation of sets offendsagainst the reductive Criteria of adequacy for individuations that are presupposed by his criticism of the ontological recognition of intensional objects. Finally, in section 4 an alternative holistic conception of individuation is outlined.

According to Peter Aczel, the inconsistency of Frege’s system in Grundgesetze is due, not to the introduction of sets, as is usually thought, but to the introduction of the Horizontal. His argument is that the principles governing sets are intuitively correct and therefore consistent, while the scheme introducing the Horizontal amounts to an internal definition of truth conflicting with Tarski’s classic result on the undefinability of truth in the object language. The aim of this paper is to show that the Horizontal is innocent: Aczel’s diagnosis is based on a mistaken view of the structure underlying Frege’s ideal language

Quines Kritik an den grundlegenden semantischen Begriffen hat zwei wesentliche Prämissen: erstens daß die Linguistik als wissenschaftliche Disziplin der methodischen Restriktion unterstellt ist, empirisch sinnlose Hypothesen und Begriffe abzulehnen, und zweitens, daß die semantischen Begriffe tatsächlich empirisch sinnlos sind. Um die Überzeugungskraft der Ausführungen Quines untersuchen zu können, werden zunächst die verschiedenen Versionen von seiner Kritik analysiert, klar gegeneinander abgegerenzt und in die Form expliziter Argumentationen gebracht. Prämissen, die in die jeweiligen Versionen implizit eingehen, werden rekonstruiert und darauf hin untersucht, ob sie durch Quines Gesamtsystem gestützt werden, bzw. überhaupt mit ihm verträglich sind. Quines Kritik erfährt so eine rein immanente Kritik mit dem Ergebnis, daß es ihm nicht gelingt, zwingende Gründe für die Ablehnung der semantischen Begriffe anzuführen.

Der erste Teil des Aufsatzes untersucht den Inhalt der These. Im Zentrum steht dabei die Frage, was Frege unter,,Wahrheit" versteht. Das Ergebnis der Untersuchung ist, daß Freges Undefinierbarkeitsthese (entgegen der üblichen Auffassung) sich nicht auf den „Inhalt des Wortes,wahr'" (bzw. auf das Wahrheitsprädikat) bezieht, sondern auf „die Wahrheit, deren Anerkennung in der Form des Behauptungssatzes liegt" (bzw. auf den Urteilsstrich. Das Kernstück des zweiten Teils der Arbeit ist eine Rekonstruktion der Argumente Freges für die These in drei Versionen. Für die Rekonstruktion wird nicht (wie sonst üblich) Freges Redundanztheorie der Wahrheit herangezogen, sondern seine Urteilstheorie. Im dritten Teil schließlich wird die Frage behandelt, ob Freges These durch Tarskis Wahrheitsdefinitionen widerlegt ist.

It is commonly assumed that the conception of truth defended by Frege in his mature period is characterized by the view that truth is not the property denoted by the predicate 'is true', but the object named by true sentences. In the present paper, I wish to make plausible an alternative interpretation according to which Frege's conception is characterized by the view that truth is what is expressed in natural language by the "form of the assertoric sentence". So construed, truth is neither an object (like the True) nor a property (like the Bedeutung of the predicate 'is true') but something of a very special kind that belongs to the same logical category as the logical relations (like subsumption). The main argument justifying this interpretation is that Frege's explication of truth does not hold of the True, but only of truth, considered as what is expressed by the form of the assertoric sentence.

Nach Auffassung von Quine ist der Realitätsbereich der Semantik auf den Bereich des beobachtbaren Sprachverhaltens beschränkt. Fragen der sprachlichen Bedeutung und sprachlichen Bezugs, die über das hinausgehen, was sich durch die Erforschung des öffentlich beobachtbaren Sprachverhalten herausbekommen lässt, sind dieser Auffassung nach keine "Tatsachenfragen", d.h. sie haben kein Fundament in der Realität. Die Arbeit verfolgt das Ziel, anhand des Aufbaus einer Theorie der "semantischen Verpflichtung" zu zeigen, dass Quines Beschränkung der semantischen Tatsachen nicht akzeptabel ist. Den Kern der Theorie bildet das folgende "Prinzip der semantischen Verpflichtung": Eine Gesamttheorie der Wirklichkeit ist aus Gründen der Kohärenz verpflichtet, diejenigen semantischen Strukturen ontologisch anzuerkennen, die vorausgesetzt werden müssen, um die Theorie formulieren zu können