Gottlob Frege

Fregesche Variationen [Variations of Frege], a Festschrift edited by Matthias Wille, assembles twelve papers in honour of Christian Thiel on the occasion of his 80th birthday in 2017. The papers ex...

نگاهی بر استدلال‌های دونالد دیویدسون در باب ضرورت زبان برای اندیشه .

Due programmi diversi si intersecano nel lavoro di Frege sui fondamenti dell’aritmetica: • Logicismo: l’aritmetica `e riducibile alla logica; • Estensionalismo: l’aritmetica `e riducibile a una teoria delle estensioni. Sia nei Fondamenti che nei Principi, Frege articola l’idea che l’aritmetica sia riducibile a una teoria logica delle estensioni.

Call a family F of subsets of a set E inductive if ∅ ∈ F and F is closed under unions with disjoint singletons, that is, if ∀X∈F ∀x∈E–X(X ∪ {x} ∈ F]. A Frege structure is a pair (E.

: Frege's philosophical writings, including the "logistic project," acquire a new insight by being confronted with Kant's criticism and Wittgenstein's logical and grammatical investigations. Between these two points a non-formalist history of logic is just taking shape, a history emphasizing the Greek and Kantian inheritance and its aftermath. It allows us to understand the radical change in rationality introduced by Gottlob Frege's syntax. This syntax put an end to Greek categorization and opened the way to the multiplicity of expressions producing (...) their own intelligibility. This article is based on more technical analyses of Frege which Claude Imbert has previously offered in other writings (see references). (shrink)

Unless you are a Frege scholar, or a philosopher of mathematics, if you are familiar at all with Frege’s work, you are most likely familiar with his groundbreaking work in the philosophy of language. You might know that Frege was a mathematician who sought to establish the covertly logical subject matter of arithmetic, a project whose demands drove Frege to his logical investigations and reflections on language. But most likely the connection between Frege’s mathematical research and his philosophy of language (...) remains elusive for you. (shrink)

avant propos This paper is basically Keenan (1992) augmented by some new types of properly polyadic quantification in natural language drawn from Moltmann (1992), Nam (1991) and Srivastav (1990). In addition I would draw the reader's attention to recent mathematical studies of polyadic quantiicationz Ben-Shalom (1992), Spaan (1992) and Westerstahl (1992). The first and third of these extend and generalize (in some cases considerably) the techniques and results in Keenan (1992). Finally I would like to acknowledge the stimulating and constructive (...) discussions ofthe earlier paper with many scholars, notably Dorit Ben-Shalom, Jaap van der Does, Hans Kamp, Uwe Mormich, Arnim von Stechow, Mats Rooth, and Ede Zimmermann. And I repeat here the acknowledgment in the earlier paper to Jim Lambek, Ed Stabler and two anonymous referees for Linguistics and Philosophy (the latter responsible for substantial improvements in the proofs - see footnote 10). (shrink)

1. There is only one rule of inference, modus ponens. This is true both in the presentations of Begriffsschrift and Grundgesetze. There are other ways of making transitions between propositions in proofs, but these are never labeled by Frege “rules of inference.” These pertain to scope of quantification, parsing of formulas, introduction of definitions, conventions for the use and replacement of the various letters, and certain structural reorganizations, ; cf. the list in Gg §48.

A frege-Russell cardinal number is a maximal class of equinumerous classes. Since anything can be numbered, A frege-Russell cardinal should contain classes whose members are cardinal numbers. This is not possible in standard set theories, Since it entails that some classes are members of members of themselves. However, A consistent set theory can be constructed in which such membership circles are allowed and in which, Consequently, Genuine frege-Russell cardinals can be defined.

Existuje překvapivě málo knih, které by se pokoušely o syntetizující pohled na analytickou filosofii. Je ovšem pravda, že ve druhé polovině našeho století se soubor filosofů, kteří se k analytické filosofii hlásí nebo kteří k ní bývají řazeni, stává natolik různorodý, že se jakákoli syntéza stává problematickou; překvapivě málo syntetizujících prací existuje ale i o ‘klasické’ analytické filosofii, to jest o analytické filosofii období zhruba od konce devatenáctého století do poloviny století dvacátého. Dejnožkova kniha je jednou z těch mála, které (...) se o něco takového pokouší, a to je třeba přivítat. Dejnožka se ovšem nesnaží podat všestranný rozbor názorů klasiků analytické filosofie; soustředí se pouze jeden aspekt jejich učení, totiž na jejich ontologii. Hned v úvodu své knihy k tomu vysvětluje, jaké opodstatnění může mít hovořit o ontologii u takového druhu filosofie, která se programově distancuje od metafyziky. Podle něj je tomu tak, že i když se někteří analytičtí filosofové někdy více či méně úspěšně vyhýbali otázkám metafyzickým (to jest otázkám po nejzákladnějších kategoriích bytí), ontologickým otázkám (to jest otázkám po povaze bytí jako takového) se v podstatě vyhnout nelze. A Dejnožka se snaží ukázat, že klasikové analytické filosofie se těmito otázkami zabývali mnohdy velice do hloubky. To je patrné zejména u Frega a Russella, kterým autor věnuje největší pozornost; avšak k těm, kteří podle Dejnožky berou ústřední otázku ontologie za svou, řadí Dejnožka i Wittgensteina i Quina (jimž se však věnuje na pouze velice omezeném prostoru - každému asi na dvanácti stránkách). (shrink)

For both Gottlob Frege and Bertrand Russell, providing a philosophical account of the concept of number was a central goal, pursued along similar logicist lines. In the present paper, I want to focus on a particular aspect of their accounts: their definitions, or reconstructions, of the natural numbers as equivalence classes of equinumerous classes. In other words, I want to examine what is often called the "Frege-Russell conception of the natural numbers" or, more briefly, the Frege-Russell numbers. My main concern (...) will be to determine the precise sense in which this conception was, or could be, meant to constitute an analysis.1 I will be mostly concerned with Frege’s views on the matter; but Russell will come up along the way, for illustration and comparison, as will some recent neo-Fregean proposals and results. The structure of the paper is as follows: In the first section, I sketch Frege's general approach. Next, I differentiate several kinds, or modes, of analysis, as further background. In the third section, I zero in on the equivalence class construction, raising the question of why it might, from a Fregean point of view, be seen as 'the right' construction, thus as an analysis in a strong sense. In the fourth section, I provide a contrasting, more conventionalist view of the matter, often associated with the Carnapian notion of explication, and expressed in some remarks by Russell. I then discuss the motivation for the Frege-Russell numbers in more depth. In the sixth section, I introduce a neo-Fregean alternative, to be examined along similar lines. Finally, I reflect further on the significance of the kinds of arguments available in this connection. (shrink)

Frege's main contributions to logic and the philosophy of mathematics are, on the one hand, his introduction of modern relational and quantificational logic and, on the other, his analysis of the concept of number. My focus in this paper will be on the latter, although the two are closely related, of course, in ways that will also play a role. More specifically, I will discuss Frege's logicist reconceptualization of the natural numbers with the goal of clarifying two aspects: the motivations (...) for its core ideas; the step-by-step development of these ideas, from Begriffsschrift through Die Grundlagen der Arithmetik and Grundgesetze der Arithmetik to Frege's very last writings, indeed even beyond those, to a number of recent "neo-Fregean" proposals for how to update them. One main development, or break, in Frege's views occurred after he was informed of Russell's antinomy. His attempt to come to terms with this antinomy has found some attention in the literature already. It has seldom been analyzed in connection with earlier changes in his views, however, partly because those changes themselves have been largely ignored. Nor has it been discussed much in connection with Frege's basic motivations, as formed in reaction to earlier positions. Doing both in this paper will not only shed new light on his response to Russell's antinomy, but also on other aspects of his views. In addition, it will provide us with a framework for comparing recent updates of these views, thus for assessing the remaining attraction of Frege's general approach. I will proceed as follows: In the first part of the paper (§1.1 and §1.2), I will consider the relationship of Frege's conception of the natural numbers to earlier conceptions, in particular to what I will call the "pluralities conception", thus bringing into sharper focus his core ideas and their motivations. In the next part (§2.1 and §2.2), I will trace the order in which these ideas come up in Frege's writings, as well as the ways in which his position gets modified along the way, both before and after Russell's antinomy.. (shrink)

Since there are non-sortal predicates Frege’s attempt to derive Arithmetic from Logic stumbles at its very first step. There are properties without a number, so the contingency of that condition shows Frege’s definition of zero is not obtainable from Logic. But Frege made a crucial mistake about concepts more generally which must be remedied, before we can be clear about those specific concepts which are numbers.

The four volumes of this collection bring together some of the major contributions to the literature on Gottlob Frege (1848-1925), one of the most formative influences on the course of philosophy during the last hundred years. The first volume provided general assessments of Frege's work and examined its historical context. The present volume deals with Frege's contributions to logic and the foundations of mathematics. The essays are arranged in order of their first publication, providing insight into the historical evolution of (...) the Frege literature. Annotation copyright by Book News, Inc., Portland, OR. (shrink)

There can be no doubt about the value of Frege's contributions to the philosophy of mathematics. First, he invented quantification theory and this was the first step toward making precise the notion of a purely logical deduction. Secondly, he was the first to publish a logical analysis of the ancestral R* of a relation R, which yields a definition of R* in second-order logic.1 Only a narrow and arid conception of philosophy would exclude these two achievements. Thirdly and very importantly, (...) the discussion in §§58-60 of the G r u n d l a g e n defends a conception of mathematical existence, to be found in Cantor (1883) and later in the writings of Dedekind and Hilbert, by basing it upon considerations about meaning which have general application, outside mathematics.2.. (shrink)

A Frege proof systemFis any standard system of prepositional calculus, e.g., a Hilbert style system based on finitely many axiom schemes and inference rules. An Extended Frege systemEFis obtained fromFas follows. AnEF-sequence is a sequence of formulas ψ1, …, ψκsuch that eachψiis either an axiom ofF, inferred from previous ψuand ψv by modus ponens or of the formq↔ φ, whereqis an atom occurring neither in φ nor in any of ψ1,…,ψi−1. Suchq↔ φ, is called an extension axiom andqa new extension (...) atom. AnEF-proof is anyEF-sequence whose last formula does not contain any extension atom. In [12], S. A. Cook and R. Reckhow proved that the pigeonhole principlePHPhas a simple polynomial sizeEF-proof and conjectured thatPHPdoes not admit polynomial sizeF-proof. In [5], S. R. Buss refuted this conjecture by furnishing polynomial sizeF-proof forPHP. Since then the important separation problem of polynomial sizeFand polynomial sizeEFhas not shown any progress.In [11], S. A. Cook introduced the systemPV, a free variable equational logic whose provable functional equalities are ‘polynomial time verifiable’ and showed that the metamathematics ofFandEFcan be developed inPVand the soundness ofEFproved inPV. In [3], S. R. Buss introduced the first order systemand showed thatis essentially a conservative extension ofPV. There he also introduced a second order system. (shrink)

Frege proved an important result, concerning the relation of arithmetic to second-order logic, that bears on several issues in linguistics. Frege’s Theorem illustrates the logic of relations like PRECEDES(x, y) and TALLER(x, y), while raising doubts about the idea that we understand sentences like ‘Carl is taller than Al’ in terms of abstracta like heights and numbers. Abstract paraphrase can be useful—as when we say that Carl’s height exceeds Al’s—without reflecting semantic structure. Related points apply to causal relations, and even (...) grammatical relations like DOMINATES(x, y). Perhaps surprisingly, Frege provides the resources needed to recursively characterize labelled expressions without characterizing them as sets. His theorem may also bear on questions about the meaning and acquisition of number words. (shrink)

In this paper, I consider two curious subsystems ofFrege's Grundgesetze der Arithmetik: Richard Heck's predicative fragment H, consisting of schema V together with predicative second-order comprehension (in a language containing a syntactical abstraction operator), and a theory T in monadic second-order logic, consisting of axiom V and 1 1-comprehension (in a language containing anabstraction function). I provide a consistency proof for the latter theory, thereby refuting a version of a conjecture by Heck. It is shown that both Heck and T (...) prove the existence of infinitely many non-logical objects (T deriving,moreover, the nonexistence of the value-range concept). Some implications concerning the interpretation of Frege's proof of referentiality and the possibility of classifying any of these subsystems as logicist are discussed. Finally, I explore the relation of T toCantor's theorem which is somewhat surprising. (shrink)

I argued that Frege does not have a metatheory in the following sense: the justifications he offers for his basic laws and rules of inference neither employ nor require a truth-predicate or metalinguistic variables. In ‘Does Frege Use a Truth-predicate in his "Justification" of the Laws of Logic?’, Dirk Greimann disputes this. As Greimann interprets Frege, (i) Frege's remarks commit him to giving a metatheoretic justification of the basic laws and rules of his logic, and (ii) Frege actually gives such (...) a justification in the early sections of Grundgesetze—although the truth-predicate that Frege employs is a non-standard one: it is neither a predicate that holds of all and only true sentences nor a predicate that holds of all and only true thoughts. I argue that Greimann's interpretation is not, in the end, true to the text, and that his non-standard view of what is required of a Tarskian truth-predicate is ultimately not viable. CiteULike Connotea Del.icio.us What's this? (shrink)

This survey article describes Frege's celebrated foundational work against the context of other late nineteenth century approaches to introducing mathematically novel "extension elements" within both algebra and geometry.

This paper offers an explanation of how philosophy of science in the second half of the 20th century came to be so conspicuously silent on the problem of how to explain the applicability of mathematics. It examines the idea of the early logicists that the analyticity of mathematics accounts for its applicability, and how this idea was transformed during Carnap's efforts to establish a consistent and substantial philosophy of mathematics within the larger framework of Logical Empiricism. I argue that at (...) the end point of this development, philosophical discussion of the applicability problem was terminated although important aspects of the logicists' original response to the applicability problem had had to be sacrificed along the way. (shrink)

The paper explores what it could mean to speak of love as involving a delight in ‘the simple actuality’ of another, or, as Buber does, of the ‘touchable’ human being as ‘unique and devoid of qualities’. Developing strands in Merleau-Ponty’s treatment of perception, it is argued that the relation between recognising this as a particular individual and recognising particular qualities in her may be close to the reverse of what might be supposed: a recognition of this distinctive smile being dependent (...) on a recognition of who this is. The fundamental place of particulars, as opposed to kinds, in our thought about those we know and care for is developed in part through a phenomenological treatment of our perception of faces. That treatment is set in a context of the justification of our judgements about who someone is, and is linked with a critique of treatments of proper names of individuals in the spirit of Frege. It is in our speaking to those we know that we find a relation to a particular that is direct—not mediated by a description of its properties—that Russell sought in ‘knowledge by acquaintance’. (shrink)

In this essay, I argue that Frege plagiarized the Stoics --and I mean exactly that-- on a large scale in his work on the philosophy of logic and language as written mainly between 1890 and his death in 1925 (much of which published posthumously) and possibly earlier. I use ‘plagiarize' (or 'plagiarise’) merely as a descriptive term. The essay is not concerned with finger pointing or casting moral judgement. The point is rather to demonstrate carefully by means of detailed evidence (...) that there are numerous (over a hundred) and extensive parallels both in formulation and --more importantly-- in content between the Stoics and Frege, parallels so plentiful that one would be hard pressed to brush them off as coincidence. These parallels include several that appear to occur in no other modern works that were published before Frege’s own and were accessible to him. Additionally, a cluster of corroborating historical data is adduced to support the suggestion, showing how easy it would have to been for Frege to plagiarize the Stoics. This (first) part of the essay is easy to read and vaguely entertaining, or so I hope. (shrink)

Diese Arbeit stellt Freges Denken in seiner Entwicklung von den Anfängen bis zum Auftreten des Widerspruch dar. Ausführlich behandelt sind die Begriffsschrift, die Erläuterungsschriften dazu, die Grundlagen der Arithmetik sowie die Texte im Übergang zu den Grundgesetzen der Arithmetik, ein- schließlich der klassischen Aufsätze Funktion und Begriff, Über Sinn und Bedeutung und Über Begriff und Gegenstand. Die Texte werden nach Chronologie und Stellung zueinander präzise aufgeschlüsselt; auch die zeitgenössischen Rezensionen und Freges wissenschaftliches Umfeld werden berücksichtigt. Freges Werk wird dadurch in (...) seiner beeindruckenden Zielstrebigkeit, Geschlossenheit und Tiefe sichtbar. Sein Zentrum ist die radikale Neufassung der Logik, ausgehend von der Grundunterscheidung von Begriff und Gegenstand, die zunächst eher unauffällig über die Zerfällung des Urteils in Funktion und Argument eingeführt und mit f(a) notiert wird. Zusammen mit der Einführung einer (Quantoren-)Notation, um die Allgemeinheit der Einsetzungen auf beiden Positionen einzuschränken, übertrifft Freges Logik die traditionelle, alle zeitgenössischen und etliche spätere an Präzision und Ausdruckskraft. Eben die grundsätzliche Trennung von Begriff und Gegenstand erweist sich aber für sein wissenschaftliches Hauptanliegen, die Ableitung der Arithmetik aus der Logik, als schwerwiegendes, letztlich nicht zu überwindendes Hindernis. Es gelingt ihm nicht, die Zahlen als „logische Gegenstände“ überzeugend einzuführen, und so zeigt er wider Willen die wesentliche Verschiedenheit von Logik und Arithmetik auf. (shrink)

In this symposium contribution I critically review the first two chapters, on Frege, in Volume 1 of The Analytic Tradition in Philosophy by Scott Soames.

An outstanding philosopher-logician, Gottlob Frege's work has received much attention in recent years. In the pursuit of Frege's main goal to solidify the foundations of mathematics and scientific work, Frege conceived a comprehensive philosophy of language and developed the main thesis of logicism, that mathematics is reducible to logic. This book contains essays covering a large range of issues related to Frege that will be of great interest to philosophers working on these issues. This volume represents an important addition to (...) the study of Frege. This book contains essays from some of the most important contemporary philosophers investigating Frege's ideas. Treating issues of contemporary interest, this book discusses topics either in a Fregean spirit or in dialogue with Frege's original views. The wide implications of Frege's views are evident in the variety of topics presented in this volume, from the Frege fundamentals to innovative interpretations that break new ground in the study of Frege. Key papers concern the ontological status of propositions and concepts, recent attempts to improve on the semantics of singular terms, the question of how to construe the content of concept-expressions, and other themes within the common grounds in which ontology and philosophical semantics intersect. (shrink)

Frege is now regarded as one of the world's greatest philosophers, and the founder of modern logic. Mark Sainsbury argues that we must depart considerably from Frege's views if we are to work towards an adequate conception of natural language. This is an outstanding contribution to philosophy of language and logic and will be invaluable to all those interested in Frege and the philosophy of language.

This is a book with curious origins, one that Dummett says he wrote "without meaning to." It is the result of a failed attempt to supply an introduction for the second edition of his outstanding work, Frege: Philosophy of Language. In surveying the reaction to the first edition, Dummett was struck by the diversity of interpretations of Frege, and since that edition contained little by way of justification of his own reading, he felt that an introduction to the second edition (...) was called for in which his positions were argued and defended. However the manuscript quickly grew into a much larger work and became the present volume. Consequently, says Dummett, there is little discussion of the truth of Frege's doctrines, the discussion instead focusing on why Frege should be read Dummett's way and containing a listing and explanation of the various textual changes he felt were required for the second edition. In fact, however, there is more space devoted to a defense of Frege's views than Dummett would have us believe in the preface, and this is all to the good since it allows the book to stand on its own to a greater degree than would otherwise have been the case. Even so, it is intended as a companion volume to FPL, and the reader will not obtain a full appreciation of it unless FPL is read first. (shrink)

Although Frege is now one of the most important figures in analytical philosophy, there are virtually no full-length studies available. Walker does not try to present all of Frege—that would be a monumental undertaking—but only to consider the philosophical aspects of his thought. Frege's theory of functions, concepts, and objects is first studied; then naming and describing are related to predication and thence to concepts; the notion of the sense of words and expressions, and then the notion of truth, especially (...) as picture-truth, is analyzed with their assistance. The last sections view Frege's general idea of the use of language and symbols, the nature of scientific laws, and the nature of numbers. The author sees Frege as tending to shift his interest from logic to ordinary language and so to the problems of expression in general; this view is reflected in the book itself. The affinities which the author sees with the work of Frege and Wittgenstein is only occasionally treated, but he does make it clear that the Tractatus owes much to Frege. Generally, this compact work will serve well in the study and interpretation of the work of the nineteenth century's greatest logician.—P. J. M. (shrink)

This highly acclaimed book is a major contribution to the philosophy of language as well as a systematic interpretation of Frege, indisputably the father of ...