Onofri [Onofri, A. 2018. ‘The Publicity of Thought.’ Philosophical Quarterly 68 (272): 521–541.] proposes an individuation criterion for thoughts that purports to satisfy both shareability (the notion that different thinkers, or a single thinker at different times, can and generally do think type-identical thoughts) and Frege's constraint (according to which two thoughts are different if it is possible for a rational subject to endorse one while rejecting the other). I argue that his proposal fails to satisfy Frege's constraint. (...) Then I propose a modification to Onofri's proposal to fix the problem. (shrink)

"By looking at Frege's lectures on logic through the eyes of the young Carnap, this book casts new light on the history of logic and analytic philosophy. As two introductory essays by Gottfried Gabriel and by Erich H. Reck and Steve Awodey explain, Carnap's notes allow us to better understand Frege's deep influence on Carnap and analytic philosophy, as well as the broader philosophical matrix from which both continental and analytic styles of thought emerged in the 20th century."--BOOK (...) JACKET. (shrink)

Frege's logicist program requires that arithmetic be reduced to logic. Such a program has recently been revamped by the "neologicist" approach of Hale and Wright. Less attention has been given to Frege's extensionalist program, according to which arithmetic is to be reconstructed in terms of a theory of extensions of concepts. This paper deals just with such a theory. We present a system of second-order logic augmented with a predicate representing the fact that an object x is the (...) extension of a concept C, together with extra-logical axioms governing such a predicate, and show that arithmetic can be obtained in such a framework. As a philosophical payoff, we investigate the status of the so-called Hume's Principle and its connections to the root of the contradiction in Frege's system. (shrink)

This is the 1991 (2nd) edition of the 1986 book (MIT Press), considered to be the classic defense of Millianism. The nature of the information content of declarative sentences is a central topic in the philosophy of language. The natural view that a sentence like "John loves Mary" contains information in which two individuals occur as constituents is termed the naive theory, and is one that has been abandoned by most contemporary scholars. This theory was refuted originally by philosopher Gottlob (...) Frege. His argument that the naive theory did not work is termed Frege's puzzle, and his rival account of information content is termed the orthodox theory. In this detailed study, Nathan Salmon defends a version of the naive theory and presents a proposal for its extension that provides a better picture of information content than the orthodox theory gives. He argues that a great deal of what has generally been taken for granted in the philosophy of language over the past few decades is either mistaken or unsupported, and consequently, much current research is focused on the wrong set of questions. Salmon dissolves Frege's puzzle as it is usually formulated and demonstrates how it can be reconstructed and strengthened to yield a more powerful objection to the naive theory. He then defends the naive theory against the new Frege puzzle by presenting an idea that yields both a surprisingly rich and powerful extension of the naive theory and a better picture of information content than that of the original orthodox theory. Nathan Salmon is Professor of Philosophy, University of California at Santa Barbara. (shrink)

It is Frege's third contribution that makes the point of departure for the present paper. Not merely did Frege show how to manipulate symbols more exactly; he also gave a searching account of what these symbols mean. Consider a philosophical problem that arises out of the simplest arithmetic. When we say that 5 = 2 + 3, what do we mean? Do we mean that 5 is identical with 2 + 3? But in some ways 5 and 2 + (...) 3 are obviously different. Or do we mean that 5 and 2 + 3 are equal but not identical, equality being a relation that falls short of complete identity? But in that case, some ordinary ways of speaking in mathematics must be false. Suppose a pupil is asked for the positive square root of 25. The phrasing of the question implies that there is one and only one. No doubt he may answer, '5'. But then it follows that the answer '2 + 3' is not allowable, since ex hypothesi 5 and 2 + 3, though equal, are not identical. Yet ordinarily the answer '2 + 3' would be regarded as strange but not as wrong. (shrink)

Frege's definition of the real numbers, as envisaged in the second volume of Grundgesetze der Arithmetik, is fatally flawed by the inconsistency of Frege's ill-fated Basic Law V. We restate Frege's definition in a consistent logical framework and investigate whether it can provide a logical foundation of real analysis. Our conclusion will deem it doubtful that such a foundation along the lines of Frege's own indications is possible at all.

Examines Frege's theory of judgement, according to which a judgement is, paradigmatically, the assertion that a particular object falls under a given concept. Throughout the book the aim is to both state Frege's views clearly and concisely, and to defend, modify or reject these where appropriate.

Concerns a problem posed, but not solved, by Frege in part III of his Grundgesetze. As a preliminary to defining ‘real number’, Frege attempts to analyse the notion of a quantitative domain. He was unaware of the previous attempt of Otto Holder to do this; it is remarked how much weaker Frege's assumptions were in deriving theorems than Holder's. Frege deals with groups on which there is a right‐invariant semilinear ordering, although he does not use this terminology. He is (...) uncertain whether it can be deduced that the ordering is also left‐invariant, and proves as much as possible without invoking the assumption that it is. The independence proof, due to Dr Peter Neumann, establishes that it could not be deduced. (shrink)

Dieser Band enthält die vier Arbeiten Freges: Begriffsschrift, eine der arithmetischen nachgebildeten Formelsprache, 1879; Anwendungen der Begriffsschrift, 1879; Über den Briefwechsel Leibnizens und Huggens mit Papin, 1881; Über den Zweck der Begriffsschrift, 1883; Über die wissenschaftliche Berechtigung einer Begriffsschrift, 1882. Frege's research work in the field of mathematical logic is of great importance for the present-day analytic philosophy. We actually owe to Frege a great amount of basical insight and exemplary research, which set up a new standard also in (...) other fields of knowledge. As the founder of mathematical logic he severely examindes the syllogisms on which arithmetic is built up. In doing so, Frege recognized that our colloquial language is inadequate to define logic structures. His notional language corresponded to the artaivicial logical language demandes by Leibniz. Frege's achievement in the field of logic were so important, that they radiated into the domain of philosophy and influenced the development of mathematical logic decisively. (shrink)

Gottlob Frege takes logic to be the science of truth throughout his career. However, the mature Frege makes remarks which seem to go against the idea that logic is the science of truth. This paper shows that we can explain away this tension in the mature Frege’s conception of logic if we accept that truth is an object, that is, the truth-vale True qua the reference of a sentence, for Frege. Even though the main thesis of this paper is a (...) conditional, I provide reasons why we ought to consider the possibility seriously that truth is an object for Frege. I also explain how we can make sense of Frege’s conception of logic as the science of truth while accepting truth is an object. (shrink)

I shall discuss some of the issues concerning a notorious doctrine of Frege that sentences are names of truth-values. I am interested in a problem raised by Kripke that the doctrine obscures the distinction between judgeable and unjudgeable contents. I shall present what I take to be Frege’s account of judgeable content: a proper expression of a judgeable content is susceptible to an analysis into a predicate and an argument-word, where a predicate is understood as a concept-word used to attribute (...) a certain property to the referent of the argument-word. In the light of this analysis, I shall argue that the doctrine does not obscure the distinction. The problem will also be discussed within the formal context of Grundgesetze. A new light will be shed on his rather peculiar conception of the symbol ‘ ${\boldsymbol \vdash}$’. (shrink)

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.

I develop a new reading of Frege’s argument for the indefinability of truth. I concentrate on what Frege literally says in the passage that contains the argument. This literal reading of the passage establishes that the indefinability argument is an arguably sound argument to the following conclusion: provided that the Fregean conception of judgment—which has recently been countered by Hanks—is correct and that truth is a property of truth-bearers, a vicious infinite regress is produced. Given this vicious regress, Frege chooses (...) to reject that truth is a property of truth-bearers. Frege’s choice leads to a unique version of the Fregean conception of judgment. His unique conception of judgment can cope with Hanks’s recent criticisms against the Fregean conception. (shrink)

Frege's extension of his distinction between Sinn and Bedeutung to predicate terms is widely considered to be problematic. Interpreters generally assume that the notion of Bedeutung comprises the name/bearer relation as a prototype and that the extension is justified only in so far as the relation of predicate terms to their alleged referents is analogous to the relation of names to their bearers. However, interpreters have generally paid insufficient attention to Frege's own dealing with the issue. By examining (...) the relevant passages in Frege's writings, I show that the standard ways of talking about Frege's ascription of Bedeutung to predicates as optional, less evident than the ascription of Sinn, and in need of justification are not in accord with Frege's own conception of predicate reference. There is no textual evidence that the extension takes place for analogical reasons and, in particular, no evidence for the claim that the name/bearer relation is used as a prototype. Frege is visibly not concerned with the relation between predicate terms and their referents, but applies the notion of Bedeutung for reasons of principle. There is indeed the invocation of an analogy, but if we consider the argument in which it occurs it appears that it does not play the justificatory role interpreters attribute to it. In sum, Frege's ascription of Bedeutung to predicates does not imply any mysterious or dubious referentiality of predicate terms. (shrink)

One of the remarkable results of Frege’s Logicism is Frege’s Theorem, which holds that one can derive the main truths of Peano arithmetic from Hume’s Principle (HP) without using Frege’s Basic Law V. This result was rediscovered by the Neo-Fregeans and their allies. However, when applied in developing a more advanced theory of mathematics, their fundamental principles—the abstraction principles—incur some problems, e.g., that of inflation. This paper finds alternative paths for such inquiry in extensionalism and object theory.

Widespread interest in Frege's general philosophical writings is, relatively speaking, a fairly recent phenomenon. But it is only very recently that his philosophy of mathematics has begun to attract the attention it now enjoys. This interest has been elicited by the discovery of the remarkable mathematical properties of Frege's contextual definition of number and of the unique character of his proposals for a theory of the real numbers. This collection of essays addresses three main developments in recent work (...) on Frege's philosophy of mathematics: the emerging interest in the intellectual background to his logicism; the rediscovery of Frege's theorem; and the reevaluation of the mathematical content of The Basic Laws of Arithmetic. Each essay attempts a sympathetic, if not uncritical, reconstruction, evaluation, or extension of a facet of Frege's theory of arithmetic. Together they form an accessible and authoritative introduction to aspects of Frege's thought that have, until now, been largely missed by the philosophical community. (shrink)

I present a novel interpretation of Frege’s attempt at Grundgesetze I §§29-31 to prove that every expression of his language has a unique reference. I argue that Frege’s proof is based on a contextual account of reference, similar to but more sophisticated than that enshrined in his famous Context Principle. Although Frege’s proof is incorrect, I argue that the account of reference on which it is based is of potential philosophical value, and I analyze the class of cases to which (...) it may successfully be applied. (shrink)

According to Frege, we need a criterion for recognising when different sentences express the same thought to make progress in logic. He himself hedged his own equipollence criterion with a number of provisos. In the literature on Frege, little attention has been paid to the problems these provisos raise. In this paper, I will argue that Fregeans have ignored these provisos at their peril. For without these provisos, Frege’s criterion yields wrong results; but with the provisos in place, it is (...) of no use for Frege’s purposes. This is connected to what Frege took to be the ‘greatest difficulty for philosophy’: natural language sentences don’t just express thoughts; they convey evaluations and communicative hints. Because of this, Frege’s recognition criterion for thoughts cannot be applied to them and we cannot make logical progress by ‘recognising a thought in different linguistic guises’. (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)

The objects of credence are the entities to which credences are assigned for the purposes of a successful theory of credence. I use cases akin to Frege's puzzle to argue against referentialism about credence : the view that objects of credence are determined by the objects and properties at which one's credence is directed. I go on to develop a non-referential account of the objects of credence in terms of sets of epistemically possible scenarios.

In this paper, I argue that a number of recent Russell interpreters, including Evans, Davidson, Campbell, and Proops, mistakenly attribute to Russell what I call ‘the received view of acquaintance’: the view that acquaintance safeguards us from misidentifying the objects of our acquaintance. I contend that Russell’s discussions of phenomenal continua cases show that he does not accept the received view of acquaintance. I also show that the possibility of misidentifying the objects of acquaintance should be unsurprising given underappreciated aspects (...) of Russell’s overall theory of knowledge and acquaintance. Finally, I consider the radical impact that Russell’s actual views on acquaintance have for our understanding of his well-known George IV case in ‘On Denoting’. In particular, I argue that Russell’s treatment of the George IV case is not a one-size-fits-all solution to Frege’s Puzzle and provides no support for the received view of acquaintance. (shrink)

In this paper, we present a formal recipe that Frege followed in his magnum opus “Grundgesetze der Arithmetik” when formulating his definitions. This recipe is not explicitly mentioned as such by Frege, but we will offer strong reasons to believe that Frege applied it in developing the formal material of Grundgesetze. We then show that a version of Basic Law V plays a fundamental role in Frege’s recipe and, in what follows, we will explicate what exactly this role is and (...) explain how it differs from the role played by extensions in his earlier book “Die Grundlagen der Arithmetik”. Lastly, we will demonstrate that this hitherto neglected yet foundational aspect of Frege’s use of Basic Law V helps to resolve a number of important interpretative challenges in recent Frege scholarship, while also shedding light on some important differences between Frege’s logicism and recent neo-logicist approaches to the foundations of mathematics. (shrink)

In Frege's Conception of Logic Patricia A. Blanchette explores the relationship between Gottlob Frege's understanding of conceptual analysis and his understanding of logic.

This paper will critically examine two solutions to Frege’s puzzle: the Millian-Russellian solution proposed by Salmon and Braun, which invokes non-semantic modes of presentation (guises, ways of believing or the like); and Fine’s relationalist solution, which appeals to semantic coordination. Special attention will be devoted to discussing the conception of modes of presentation as mental files and to elucidating the nature of coordination. A third solution to Frege’s puzzle will be explored which, like Salmon’s and Braun’s, adopts the Millian-Russellian semantics (...) but, like Fine’s, involves coordination instead of modes of presentation; however, coordination will not be conceived as a semantic relation but as a cognitive and subjective relation, which provides no contribution to semantic content. This novel Millian-Russellian account involving cognitive coordination will be labelled cognitive relationism. (shrink)

Two thoughts about the concept of number are incompatible: that any zero or more things have a number, and that any zero or more things have a number only if they are the members of some one set. It is Russell's paradox that shows the thoughts incompatible: the sets that are not members of themselves cannot be the members of any one set. The thought that any things have a number is Frege's; the thought that things have a number (...) only if they are the members of a set may be Cantor's and is in any case a commonplace of the usual contemporary presentations of the set theory that originated with Cantor and has become ZFC.In recent years a number of authors have examined Frege's accounts of arithmetic with a view to extracting an interesting subtheory from Frege's formal system, whose inconsistency, as is well known, was demonstrated by Russell. These accounts are contained in Frege's formal treatise Grundgesetze der Arithmetik and his earlier exoteric book Die Grundlagen der Arithmetik. We may describe the two central results of the recent re-evaluation of his work in the following way: Let Frege arithmetic be the result of adjoining to full axiomatic second-order logic a suitable formalization of the statement that the Fs and the Gs have the same number if and only if the F sand the Gs are equinumerous. (shrink)

According to Frege, neither demonstratives nor indexicals are singular terms; only a demonstrative together with ‘circumstances accompanying its utterance’ has sense and singular reference. While this view seems defensible for demonstratives, where demonstrations serve as non-verbal signs, indexicals, especially pure indexicals like ‘I’, ‘here’, and ‘now’, seem not to be in need of completion by circumstances of utterance. In this paper I argue on the basis of independent reasons that indexicals are in fact in need of completion; I identify the (...) completers as uses of circumstances of utterance by the speaker; and I show how these uses together with the utterance of indexical sentences express thoughts. The starting point of the paper is a criticism of Kripke’s and Künne’s alternative treatment of indexicals in Frege’s framework. (shrink)

In this paper, we explore Fregean metatheory, what Frege called the New Science. The New Science arises in the context of Frege’s debate with Hilbert over independence proofs in geometry and we begin by considering their dispute. We propose that Frege’s critique rests on his view that language is a set of propositions, each immutably equipped with a truth value (as determined by the thought it expresses), so to Frege it was inconceivable that axioms could even be considered to be (...) other than true. Because of his adherence to this view, Frege was precluded from the sort of metatheoretical considerations that were available to Hilbert; but from this, we shall argue, it does not follow that Frege was blocked from metatheory in toto. Indeed, Frege suggests in Die Grundlagen der Geometrie a metatheoretical method for establishing independence proofs in the context of the New Science. Frege had reservations about the method, however, primarily because of the apparent need to stipulate the logical terms, those terms that must be held invariant to obtain such proofs. We argue that Frege’s skepticism on this score is not warranted, by showing that within the New Science a characterization of logical truth and logical constant can be obtained by a suitable adaptation of the permutation argument Frege employs in indicating how to prove independence. This establishes a foundation for Frege’s metatheoretical method of which he himself was unsure, and allows us to obtain a clearer understanding of Frege’s conception of logic, especially in relation to contemporary conceptions. (shrink)

Number words seemingly function both as adjectives attributing cardinality properties to collections, as in Frege’s ‘Jupiter has four moons’, and as names referring to numbers, as in Frege’s ‘The number of Jupiter’s moons is four’. This leads to what Thomas Hofweber calls Frege’s Other Puzzle: How can number words function as modifiers and as singular terms if neither adjectives nor names can serve multiple semantic functions? Whereas most philosophers deny that one of these uses is genuine, we instead argue that (...) number words, like many related expressions, are polymorphic, having multiple uses whose meanings are systematically related via type shifting. (shrink)

Frege's linguistic views are exemplified by an analysis of the following topics: proper and common names, the definite and the indefinite article, the singular and plural distinction, words and sentences, together with the role of the copula, and the relationship of syntactical and semantical categories. His endeavour to overcome the ambiguities of natural language inherently connected with his logical investigations failed. In fact, his conceptions are relying on accidental features of a particular natural language, namely German. Therefore, they are (...) neither valid in general nor relevant from the logical point of view. They are influenced rather by his philosophical prejudices than by empirical results obtained in comparative philology and linguistics at all. (shrink)

(Translation of Frege's Grundgesetze II, §§ 86-137).

Frege held that singular terms can refer only to objects, not to concepts. I argue that the counter-intuitive consequences of this claim ('the concept paradox') arise from Frege's mirroring principle that an incomplete expression can only express an incomplete sense and stand for an incomplete reference. This is not, as is sometimes thought, merely because predicates and singular terms cannot be intersubstituted salva veritate ( congruitate ). The concept paradox, properly understood, poses therefore a different, harder, challenge. An investigation (...) of the foundations of the mirroring principle also sheds light on the role which language plays in Frege's epistemology of logic. (shrink)

Michael Dummett, following an established line of reasoning, has interpreted Frege as a realist. But his claim that Frege was arguing against a dominant idealism is untenable. While there are passages in Frege's writings that seem to support a realistic interpretation, others are irreconcilable with it. The issue can be resolved only by examining the historical context. Frege's thought is, in fact, related to the philosophy of Hermann Lotze. Frege is best regarded as a transcendental idealist in the (...) Lotze-Kant tradition. His contextual principle is a linguistic version of Kant's principle of the transcendental unity of judgment. By ignoring the historical context Dummett has been led to misinterpret the precise role of the contextual principle in Frege's thought. (shrink)

Two topics are presently discussed. first, the distinction frege draws between two kinds of laws, natural and normative. secondly, we show how a remark made by frege with respect to different notions of truth is related to the analysis of meaning by family resemblances, as stressed later by wittgenstein. the historical dimension of family formation is discussed and references to 18th and 19th-century philosophers holding similar views are made. (edited).

This paper argues that a particular point raised by Schröder – that Frege's logical notation fails to be modelled on arithmetical notation – is based on a misunderstanding, for the modelling was meant as conceptual, rather than notational.

This paper discusses the question to what extent Frege made serious use of semantical notions such as reference and truth. It focuses on his apparent uses of these notions in his apparently semantical discussions of his formal system in Grundgesetze der Arithmetik and defends the view that they are to be taken at face value. This paper is in some ways a companion to "Grundgesetze der Arithmetik I §§29-32", in which there is an extended, but mostly technical, discussion of (...) class='Hi'>Frege's attempt to prove that every well-formed expression in his formal language denotes: This paper contains more in the way of a discussion of the wider, interpretive significance of the technical interpretation given there. (shrink)

Michael Dummett has advanced, very influentially, the view that Frege means truth conditions by his notion of thought (Gedanke). My aim in this paper is to argue that Dummett and others are mistaken in this claim. First, Frege's aversion of the correspondence theory of truth does not square well with Dummett's claim. Secondly, and more importantly, Grundgesetze I, §32, is the only place where Frege even appears to be talking about truth conditions in connection with his notion of thought (...) -- and even there, I shall show, he does not really identify thoughts with truth conditions, but states only the triviality that a statement such as, say, 'Leibniz is a philosopher' expresses the thought that Leibniz is a philosopher. (shrink)

[Translation of Frege's 'Über das Trägheitsgesetz].

[Translation of Frege's 'Gedankengefüge' (1923)].

In this dissertation I explore Frege’s conception of truth. In particular I defend the thesis that Frege in his mature career takes truth to be an object, i.e., the True qua the reference of true sentences. In the literature on truth Frege has been usually taken to be a truth deflationist or a truth primitivist. Indeed Frege leaves a number of comments that sound like typical deflationist claims and his famous indefinability argument is the most discussed argument for primitivism. However, (...) Frege is neither a deflationist nor a primitivist. His deflationist remarks and the indefinability argument are rather his arguments that truth is an object. -/- For Frege judging—and its verbal counterpart asserting—is always acknowledging the truth of a truth-bearer. Thus, if truth is an object for him, his conception of judgment ought to also be adjusted accordingly. Indeed Frege shows how we can understand judgment qua acknowledgment of truth if truth is an object. Specifically, judging that p is identifying the True with the reference of ‘p’ non-judgmentally, i.e., without judging that p is identical with the reference of ‘p’. Frege’s conception of judgment impacts his conception of knowledge because the act of judging is that of producing knowledge. In a nutshell our act of judging and the knowledge we produce by it are epistemically grounded in our objectual knowledge of the True. If we take this point into account, we can develop a new reading of Frege’s claim that logic is the science of truth. -/- The suggested reading of Frege’s conception of truth and related notions can make a contribution to contemporary philosophical problems. First, Frege’s conception of judgment can cope with Peter Hanks’s recent criticisms of the Fregean picture of judgment in general. Secondly, his conception of assertion can explain the connection between truth and assertion in a novel way. Lastly, Frege’s conception of knowledge can be developed into a new theory of knowledge where objectual knowledge is more fundamental than propositional knowledge. (shrink)

Controversy remains over exactly why Frege aimed to estabish logicism. In this essay, I argue that the most influential interpretations of Frege's motivations fall short because they misunderstand or neglect Frege's claims that axioms must be self-evident. I offer an interpretation of his appeals to self-evidence and attempt to show that they reveal a previously overlooked motivation for establishing logicism, one which has roots in the Euclidean rationalist tradition. More specifically, my view is that Frege had two notions (...) of self-evidence. One notion is that of a truth being foundationally secure, yet not grounded on any other truth. The second notion is that of a truth that requires only clearly grasping its content for rational, a priori justified recognition of its truth. The overarching thesis I develop is that Frege required that axioms be self-evident in both senses, and he relied on judging propositions to be self-evident as part of his fallibilist method for identifying a foundation of arithmetic. Consequently, we must recognize both notions in order to understand how Frege construes ultimate foundational proofs, his methodology for discovering and identifying such proofs, and why he thought the propositions of arithmetic required proof. (shrink)

The form of the sentence, as it is understood in contemporary semantics and linguistics, is functional. This paper interprets the metaphors in which Frege shows what the functional sentence means, arguing that Frege's sentence is neither an adequate translation of natural language nor of use in feminist theorizing.

Departing from the dominant theories of Frege, Russell and Mill, Kit Fine has sketched a novel solution to Frege’s puzzle in his book Semantic Relationism. In this article, I briefly discuss the puzzle in its various forms and the attempted solutions of Frege and Russell. I then explicate the essential features of the new theory and critically appraise the mechanism suggested by Fine to solve the puzzle. I show that Semantic Relationism fails to address the concerns raised in the puzzle.

What makes certain definitions fruitful? And how can definitions play an explanatory role? The purpose of this paper is to examine these questions via an investigation of Frege’s treatment of definitions. Specifically, I pursue this issue via an examination of Frege’s views about the scientific unification of logic and arithmetic. In my view, what interpreters have failed to appreciate is that logicism is a project of unification, not reduction. For Frege, unification involves two separate steps: (1) an account of the (...) content expressed by arithmetical claims and (2) the justification of that content. The distinction between these steps allows us to see that there are two notions of definition at play in Frege’s logicist work, viz., one concerned with conceptual analysis, the other concerned with the construction of gap-free proof. I then use this discussion to explain how Frege employs his definitions to defend an epistemological thesis about arithmetic, and to clarify Grundlagen’s fruitfulness condition of definitions, and thereby address two interpretive puzzles from the recent literature. (shrink)

ABSTRACT In this paper, I argue that a number of influential Millian responses to Frege’s puzzle, which consist in denying that Frege’s data apply to natural languages, are not viable if logic is to play its role in legitimizing the logical appraisal of rational subjects. A notion of validity which does justice to the normativity of logic must make room for a distinction between valid inferences and enthymemes. I discuss the prospects of formal, relevant and manifest validity as candidates for (...) a notion which complies with this desideratum. Their success, or failure is argued to hang on the viability of a semantical account of de jure co-reference, which is in tension with standard Millian tenets. I conclude that these Millian theories face the following dilemma: either accept that there is no notion of logical validity which makes logic normative for reasoning, thus jeopardizing our well entrenched practices of rational appraisal; or accept that de jure co-reference is a real semantical relation. (shrink)

I shall make two main claims. My first main claim is that Frege started out with a view of logic that is closer to Kant’s than is generally recognized, but that he gradually came to reject this Kantian view, or at least totally to transform it. My second main claim concerns Frege’s reasons for distancing himself from the Kantian conception of logic. It is natural to speculate that this change in Frege’s view of logic may have been spurred by a (...) desire to establish the logicality of the axiom system he needed for his logicist reduction, including the infamous Basic Law V. I admit this may have been one of Frege’s motives. But I shall argue that Frege also had a deeper and more interesting reason to reject his early Kantian view of logic, having to do with his increasingly vehement anti-psychologism. (shrink)

Frege’s writings contain arguments for the thesis (i) that a thought expressed by a sentence S is a structured object whose composition pictures the composition of S, and for the thesis (ii) that a thought is an unstructured object. I will argue that Frege’s reasons for both (i) and (ii) are strong. Frege’s explanation of the difference in sense between logically equivalent sentences rests on assumption (i), while Frege’s claim that the same thought can be decomposed differently makes (ii) plausible. (...) Thoughts are supposed to do work that requires that they be structured and work that requires that they be unstructured. But this cannot be! While the standard response to this problem is to reject either (i) or (ii), I propose a charitable repair in the spirit of Frege’s theory that accepts both. The key idea can be found in Frege’s Basic Laws of Arithmetic(BL, GGA). Frege argues that the thought expressed by a sentence is determined by the truth-conditions that can be derived from the semantic axioms for the sentence constituents. The fact that the same axiomatic truth-condition can be derived in different ways from different semantic axioms suggests a Fregean solution of the dilemma: A thought is a type that is instantiated by all sequences of senses (decomposed thoughts) that have the same axiomatic truth-conditions. This allows for multiple decomposability of the same thought (for different decomposed thoughts can have the same axiomatic truth-conditions) and for a notion of containment (the decomposed thought contains those senses whose semantic axioms are needed in the derivation of the truth-conditions). My proposal combines the virtues of (i) and (ii) without inheriting their vices. (shrink)