_Rationality Through Reasoning_ answers the question of how people are motivated to do what they believe they ought to do, built on a comprehensive account of normativity, rationality and reasoning that differs significantly from much existing philosophical thinking. Develops an original account of normativity, rationality and reasoning significantly different from the majority of existing philosophical thought Includes an account of theoretical and practical reasoning that explains how reasoning is something we ourselves do, rather than something that happens in us Gives (...) an account of what reasons are and argues that the connection between rationality and reasons is much less close than many philosophers have thought Contains rigorous new accounts of oughts including owned oughts, agent-relative reasons, the logic of requirements, instrumental rationality, the role of normativity in reasoning, following a rule, the correctness of reasoning, the connections between intentions and beliefs, and much else. Offers a new answer to the ‘motivation question’ of how a normative belief motivates an action. (shrink)

This is a thorough treatment of first-order modal logic. The book covers such issues as quantification, equality (including a treatment of Frege's morning star/evening star puzzle), the notion of existence, non-rigid constants and function symbols, predicate abstraction, the distinction between nonexistence and nondesignation, and definite descriptions, borrowing from both Fregean and Russellian paradigms.

The book features the complete text of the Notesi in a critical edition, with a detailed discussion of the circumstances in which they were compiled, leading to ...

Parts of the book date back to and some of the concluding remarks on ethics and the will may have been composed still earlier, when Wittgenstein admired ...

The great three-volume Principia Mathematica is deservedly the most famous work ever written on the foundations of mathematics. Its aim is to deduce all the fundamental propositions of logic and mathematics from a small number of logical premisses and primitive ideas, and so to prove that mathematics is a development of logic. This abridged text of Volume I contains the material that is most relevant to an introductory study of logic and the philosophy of mathematics (more advanced students will wish (...) to refer to the complete edition). It contains the whole of the preliminary sections (which present the authors' justification of the philosophical standpoint adopted at the outset of their work); the whole of Part 1 (in which the logical properties of propositions, propositional functions, classes and relations are established); section 6 of Part 2 (dealing with unit classes and couples); and Appendices A and B (which give further developments of the argument on the theory of deduction and truth functions). (shrink)

This book aims to develop certain aspects of Gottlob Frege’s theory of meaning, especially those relevant to intensional logic. It offers a new interpretation of the nature of senses, and attempts to devise a logical calculus for the theory of sense and reference that captures as closely as possible the views of the historical Frege. (The approach is contrasted with the less historically-minded Logic of Sense and Denotation of Alonzo Church.) Comparisons of Frege’s theory with those of Russell and others (...) are given. It is in the end shown that developing Frege’s theory in these ways reveals serious problems hitherto largely unnoticed, including those possibly rendering a Fregean intensional logic inconsistent even if his naïve class theory is excluded. (shrink)

"Although almost unknown in his lifetime, it was Gottlob Frege (1848-1925) who set the agenda for much of twentieth-century philosophy." "His 'concept script' overthrew Aristotle's long-established system of logic and underlies all subsequent developments in the subject. His radically new approach to the foundations of arithmetic, based on fresh definitions of the terms 'zero', 'one' and 'successor', revolutionized our understanding of mathematics. And his important insights into the nature of language and meaning provided the framework for Russell, Wittgenstein and twentieth-century (...) linguistic analysis. In this superb survey of his evolving ideas, Anthony Kenny explains and assesses the full range of Frege's work and reveals why it still forms an ideal introduction to modern analytic philosophy. Even after seventy years, he concludes, Frege remains an absolutely central figure, one of those rare thinkers who wrote 'prose which is accessible and attractive on first acquaintance and yet which repays rereading over a lifetime'."--BOOK JACKET.Title Summary field provided by Blackwell North America, Inc. All Rights Reserved. (shrink)

überall einen richtigen Gebrauch der reinen Vernunft giebt, in welchem Fall es auch einen Canon derselben geben muß, so wird dieser nicht den speculativen, sondernden pr.ntischen Vernunftgebrauch betreffen, den wir also iezt ...

Analytic philosophy has become the dominant philosophical tradition in the English-speaking world. This book illuminates that tradition through a historical examination of a crucial period in its formation: the rejection of Idealism by Bertrand Russell and G.E. Moore at the beginning of the twentieth century, and the subsequent development of Russell's thought in the period before the First World War.

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.

Anscombe guides us through the Tractatus and, thereby, Wittgenstein's early philosophy as a whole. She shows in particular how his arguments developed out of the discussions of Russell and Frege. This reprint is of the fourth, corrected edition.

Gottlob Frege (1848-1925) was one of the founders of analytical philosophy and the greatest innovator in logic since Aristotle. He introduced many influential philosophical ideas, such as the distinctions between function and argument, or between sense and reference. However, his thought is not readily accessible to the non- expert. His conception of logic, which was crucial to his grand project, the reduction of arithmetic to logic, is especially difficult to grasp. This book provides a lucid and critical introduction to Frege's (...) logic, as he developed it in his groundbreaking first book Begriffsschrift (Conceptual Notation, 1879). It guides the reader directly to the core of Frege's philosophy, and to some of the most pertinent issues in contemporary philosophy of language, logic, mathematics, and mind. Unlike most other books, this commentary explains Frege's own logical notation, allowing students to study and appreciate those aspects of his work that he valued most but are least understood today. (shrink)

Peter Hanks defends a new theory about the nature of propositional content, according to which the basic bearers of representational properties are particular mental or spoken actions. He explains the unity of propositions and provides new solutions to a long list of puzzles and problems in philosophy of language.

Gottlob Frege and Ludwig Wittgenstein (the later Wittgenstein) are often seen as polar opposites with respect to their fundamental philosophical outlooks: Frege as a paradigmatic "realist", Wittgenstein as a paradigmatic "anti-realist". This opposition is supposed to find its clearest expression with respect to mathematics: Frege is seen as the "arch-platonist", Wittgenstein as some sort of "radical anti-platonist". Furthermore, seeing them as such fits nicely with a widely shared view about their relation: the later Wittgenstein is supposed to have developed his (...) ideas in direct opposition to Frege. The purpose of this paper is to challenge these standard assumptions. I will argue that Frege's and Wittgenstein's basic outlooks have something crucial in common; and I will argue that this is the result of the positive influence Frege had on Wittgenstein. (shrink)

One of the most striking differences between Frege's Begriffsschrift (logical system) and standard contemporary systems of logic is the inclusion in the former of the judgement stroke: a symbol which marks those propositions which are being asserted , that is, which are being used to express judgements . There has been considerable controversy regarding both the exact purpose of the judgement stroke, and whether a system of logic should include such a symbol. This paper explains the intended role of the (...) judgement stroke in a way that renders it readily comprehensible why Frege insisted that this symbol was an essential part of his logical system. The key point here is that Frege viewed logic as the study of inference relations amongst acts of judgement , rather than – as in the typical contemporary view – of consequence relations amongst certain objects (propositions or well-formed formulae). The paper also explains why Frege's use of the judgement stroke is not in conflict with his avowed anti-psychologism, and why Wittgenstein's criticism of the judgement stroke as 'logically quite meaningless' is unfounded. The key point here is that while the judgement stroke has no content , its use in logic and mathematics is subject to a very stringent norm of assertion. (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)

Does the English demonstrative pronoun 'that' (including complex demonstratives of the form 'that F') have sense and reference? Unlike many other philosophers of language, Frege answers with a resounding 'No'. He held that the bearer of sense and reference is a so-called 'hybrid proper name' (Künne) that contains the demonstrative pronoun and specific circumstances of utterance such as glances and acts of pointing. In this paper I provide arguments for the thesis that demonstratives are hybrid proper names. After outlining why (...) Frege held the hybrid proper name view, I will defend it against recent criticism, and argue that it is superior to views that take demonstrative pronouns to be the bearer of semantic properties. (shrink)

In the opening to his late essay, Der Gedanke, Frege asserts without qualification that the word "true" points the way for logic. But in a short piece from his Nachlass entitled "My Basic Logical Insights", Frege writes that the word true makes an unsuccessful attempt to point to the essence of logic, asserting instead that "what really pertains to logic lies not in the word "true" but in the assertoric force with which the sentence is uttered". Properly understanding what Frege (...) takes to be at issue here is crucial for understanding his conception of logic and, in particular, what he takes to be its normative status vis-à-vis judgement, assertion, and inference. In this paper, I focus my attention on clarifying the latter claim and Frege's motivations for making it, exposing what I take to be a fundamental tension in Frege's conception of logic. Finally, I discuss whether Frege's deployment of the horizontal in his mature Begriffsschrift helps to resolve this tension. (shrink)

This paper brings to light a new puzzle for Frege interpretation, and offers a solution to that puzzle. The puzzle concerns Frege’s judgement-stroke (‘|’), and consists in a tension between three of Frege’s claims. First, Frege vehemently maintains that psychological considerations should have no place in logic. Second, Frege regards the judgementstroke—and the associated dissociation of assertoric force from content, of the act of judgement from the subject matter about which judgement is made—as a crucial part of his logic. Third, (...) Frege holds that judging is an inner mental process, and that the distinction marked by the judgement-stroke, between entertaining a thought and judging that it is true, is a psychological distinction. I argue that what initially looks like confusion here on Frege’s part appears quite reasonable when we remind ourselves of the differences between Frege’s conception of logic and our own. (shrink)

Attention to the conversational role of alethic terms seems to dominate, and even sometimes exhaust, many contemporary analyses of the nature of truth. Yet, because truth plays a role in judgment and assertion regardless of whether alethic terms are expressly used, such analyses cannot be comprehensive or fully adequate. A more general analysis of the nature of truth is therefore required – one which continues to explain the significance of truth independently of the role alethic terms play in discourse. We (...) undertake such an analysis in this paper; in particular, we start with certain elements from Kant and Frege, and develop a construct of truth as a normative modality of cognitive acts (e.g., thought, judgment, assertion). Using the various biconditional T-schemas to sanction the general passage from assertions to (equivalent) assertions of truth, we then suggest that an illocutionary analysis of truth can contribute to its locutionary analysis as well, including the analysis of diverse constructions involving alethic terms that have been largely overlooked in the philosophical literature. Finally, we briefly indicate the importance of distinguishing between alethic and epistemic modalities. (shrink)

An implication is a proposition, a consequence is a relation between propositions, and an inference is act of passage from certain premise-judgements to another conclusion-judgement: a proposition is true, a consequence holds, whereas an inference is valid. The paper examines interrelations, differences, refinements and linguistic renderings of these notions, as well as their history. The truth of propositions, respectively the holding of consequences, are treated constructively in terms of verification-objects. The validity of an inference is elucidated in terms of the (...) existence of a chain of immediately evident steps linking premises and conclusion. (shrink)

The paper argues that Wittgenstein's criticisms of Frege and Russell's assertion sign are, a bottom, criticisms of a common flaw in these philosophers' early conceptions of the proposition. Each philosopher offers an account of the proposition that *seems* to suggest that a sentence cannot get so far as to say something without the addition of the assertion sign. This leads to the mistaken idea that there is a coherent notion of "logical assertion.".

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. (shrink)

As is well-known, the formal system in which Frege works in his Grundgesetze der Arithmetik is formally inconsistent, Russell?s Paradox being derivable in it.This system is, except for minor differences, full second-order logic, augmented by a single non-logical axiom, Frege?s Axiom V. It has been known for some time now that the first-order fragment of the theory is consistent. The present paper establishes that both the simple and the ramified predicative second-order fragments are consistent, and that Robinson arithmetic, Q, is (...) relatively interpretable in the simple predicative fragment. The philosophical significance of the result is discussed. (shrink)

Frege’s distinction between sense (Sinn) and meaning (Bedeutung) is his most influential contribution to philosophy, however central it was to his own projects, and however he may have conceived its importance. Philosophers of language influenced by, or reacting against the distinction, and historians of philosophy commenting on it, have all contributed to the voluminous literature surrounding it.1 Nonetheless in this essay I hope to shed new light on the distinction by considering it in the context of the development of Frege’s (...) thought, and connecting it more intimately than is usually done with Frege’s interests in logic, especially his views on judgment, truth and inference, which were central to his own projects as he conceived them. (shrink)

Frege seems committed to the thesis that the senses of the fundamental notions of arithmetic remain stable and are stably grasped by thinkers throughout history. Fully competent practitioners grasp those senses clearly and distinctly, while uncertain practitioners see them, the very same senses, “as if through a mist”. There is thus a common object of the understanding apprehended to a greater or lesser degree by thinkers of diverging conceptual competence. Frege takes the thesis to be a condition for the possibility (...) of the rational intelligibility of mathematical practice. I argue however that the idea that senses could be grasped as a matter of degree is in tension with the constitutive theses that Frege held with regard to sense. Given those theses, there can in fact be no such thing as misty grasp of sense, since any uncertainty as to the logical features of a given sense will entail that one is getting hold of a different sense or of no sense at all. I consider various ways of resolving the tension and conclude that Frege’s thesis cannot be defended if we take it to be a thesis about our competence with concepts. This leaves unresolved what I call the problem of normative guidance, that is, the problem of explaining how the fundamental notions of logic and arithmetic can provide inferential guidance to thinkers. (shrink)

Thomas Ricketts has developed a powerful interpretation of Frege on judgment, truth and logic. Recently, Ricketts has modified his reading, holding that judgment is an act of knowledge-acquisition; this rules out incorrect judgment. I argue that Ricketts goes too far here. I criticize the textual basis for Ricketts's new view, and show that the interpretive problems which led him to this change can be met without such extreme measures. Thus, I defend Ricketts' earlier view against his own later modification. Along (...) the way I discuss Kant and Brentano on judgment, and I explore Fregean argument concerning the objectivity of truth. (shrink)

The paper scrutinizes Frege's Euclideanism - his view of arithmetic and geometry as resting on a small number of self-evident axioms from which non-self-evident theorems can be proved. Frege's notions of self-evidence and axiom are discussed in some detail. Elements in Frege's position that are in apparent tension with his Euclideanism are considered - his introduction of axioms in The Basic Laws of Arithmetic through argument, his fallibilism about mathematical understanding, and his view that understanding is closely associated with inferential (...) abilities. The resolution of the tensions indicates that Frege maintained a sophisticated and challenging form of rationalism, one relevant to current epistemology and parts of the philosophy of mathematics. (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)

According to Frege, judgement is the ‘logically primitive activity’. So what is judgement? In his mature work, he characterizes judging as ‘acknowledging the truth’ (‘Anerkennen der Wahrheit’). Frege’s remarks about judging as acknowledging the truth of a thought require further elaboration and development. I will argue that the development that best suits his argumentative purposes takes acknowledging the truth of a thought to be a non-propositional attitude like seeing an object; it is a mental relation between a thinker, a thought, (...) and an object, namely a truth-value. (shrink)