In the section “Validity and Existence in Logik, Book III,” I explain Lotze’s famous distinction between existence and validity in Book III of Logik. In the following section, “Lotze’s Platonism,” I put this famous distinction in the context of Lotze’s attempt to distinguish his own position from hypostatic Platonism and consider one way of drawing the distinction: the hypostatic Platonist accepts that there are propositions, whereas Lotze rejects this. In the section “Two Perspectives on Frege’s Platonism,” I argue that this (...) is an unsatisfactory way of reading Lotze’s Platonism and that the Ricketts-Reck reading of Frege is in fact the correct way of thinking about Lotze’s Platonism. (shrink)

This paper argues that Paul Ricoeur’s hermeneutical philosophy attempts to reopen the question of human transcendence in contemporary terms. While his conception of language as self-transcending is deeply Husserlian, Ricoeur also responds to the analytical challenge when he deploys a basic distinction in Fregean logic in order to clarify Heidegger’s phenomenology of world. Ricoeur’s commitment to a transcendental view is evident in his conception of narrative, which enables him to emphasize the role of the performative in literary reading. The meaning (...) of the self in time provides Ricoeur with a discursive basis for distinguishing his own position from that of Kant and other philosophers in the transcendental tradition. (shrink)

During the past few decades, a radical shift has occurred in how philosophers conceive of the relation between science and philosophy. A great number of analytic philosophers have adopted what is commonly called a ‘naturalistic’ approach, arguing that their inquiries ought to be in some sense continuous with science. Where early analytic philosophers often relied on a sharp distinction between science and philosophy—the former an empirical discipline concerned with fact, the latter an a priori discipline concerned with meaning—philosophers today largely (...) follow Willard Van Orman Quine (1908-2000) in his seminal rejection of this distinction. -/- This book offers a comprehensive study of Quine’s naturalism. Building on Quine’s published corpus as well as thousands of unpublished letters, notes, lectures, papers, proposals, and annotations from the Quine archives, this book aims to reconstruct both the nature (chapters 2-4) and the development (chapter 5-7) of his naturalism. As such, this book aims to contribute to the rapidly developing historiography of analytic philosophy, and to provide a better, historically informed, understanding of what is philosophically at stake in the contemporary naturalistic turn. (shrink)

Sets are multitudes which are also unities. It is surprising that the fact that multitudes are also unities leads to no contradictions: this is the main fact of mathematics.Kurt Gödel (Hao Wang,A Logical Journey: From Gödel to Philosophy)In what sense can something be at the same time one and many? The problem is familiar since Plato (for example,Republic524e). In recent times, Whitehead and Russell, inPrincipia Mathematica,have been struck by the difficulty of the problem: ‘If there is such an object as (...) a class, it must be in some senseoneobject, yet it is only of classes that many can be predicated. Hence, if we admit classes as objects, we must suppose that the same object can be both one and many, which seems impossible.' It is, however, in Frege's great work,The Foundations of Arithmetic(henceforth,Grundlagen),that many see the final resolution of the old question: how can something be at the same time one and many? (shrink)

The project behind this and the following1 special issue of Angelaki first assumed concrete form in the shape of a three-day international conference, “Continental Philosophy and the Sciences,” hel...

Frege's docent's dissertation Rechnungsmethoden, die sich auf eine Erweiterung des Grössenbegriffes gründen(1874) contains indications of a bold attempt to extend arithmetic. According to it, arithmetic means the science of magnitude, and magnitude must be understood structurally without intuitive support. The main thing is insight into the formal structure of the operation of ?addition?. It turns out that a general ?magnitude domain? coincides with a (commutative) group. This is an interesting connection with simultaneous developments in abstract algebra. As his main application, (...) Frege studies iterations of functions. He does not yet pose the question of existence proofs. Measurement of magnitudes is also connected to numbers, but the discussion is here ambiguous in a way which calls for the systematic account of numbers in Grundgesetze. (shrink)

According to what Jonathan Bennett calls the Kant–Frege view of existence, Frege gave solid logical foundations to Kant’s claim that existence is not a real predicate. In this article I will challenge Bennett’s claim by arguing that although Kant and Frege agree on what existence is not, they agree neither on what it is nor on the importance and justification of existential propositions. I identify three main differences: first, whereas for Frege existence is a property of a concept, for Kant (...) it is a relational property pertaining between the concept and intuition of an object. Second, whereas for Frege truth about individuals presupposes their existence, for Kant truth is in many cases independent of the existence of objects. Third, whereas Frege binds logic to existence and removes modalities from logic, for Kant existence is a modal category that is emphatically removed from the domain of logic and set in the core of metaphysics. Due to these differences in Kant’s and Frege’s theories of existence, Frege cannot be seen as giving logical clarity to Kant’s view. (shrink)

The issues surrounding the Caesar problem are assumed to be inert as far as ongoing mathematics is concerned. This paper aims to correct this impression by spelling out the ways that, in their historical context, Frege's remarks would have had considerable resonance with work that other mathematicians such as Riemann and Dedekind were doing. The search for presentation‐independent characterizations of objects and global definitions was seen as bound up with fundamental methodological questions in complex analysis and number theory.

Well over a century after its introduction, Frege's two-dimensional Begriffsschrift notation is still considered mainly a curiosity that stands out more for its clumsiness than anything else. This paper focuses mainly on the propositional fragment of the Begriffsschrift, because it embodies the characteristic features that distinguish it from other expressively equivalent notations. In the first part, I argue for the perspicuity and readability of the Begriffsschrift by discussing several idiosyncrasies of the notation, which allow an easy conversion of logically equivalent (...) formulas, and presenting the notation's close connection to syntax trees. In the second part, Frege's considerations regarding the design principles underlying the Begriffsschrift are presented. Frege was quite explicit about these in his replies to early criticisms and unfavorable comparisons with Boole's notation for propositional logic. This discussion reveals that the Begriffsschrift is in fact a well thought-out and carefully crafted notation that intentionally exploits the possibilities afforded by the two-dimensional medium of writing like none other. (shrink)

ABSTRACTHere, I pursue consequences, for the interpretation of Sellars’ critique of the ‘Myth of the Given’, of separating the modal significance that Kant attributed to empirical intuition from th...

The paper examines Davidson′s discussion of Frege on the problem of predication. Simple declarative sentences are unities that are true or false; how do predicates contribute to this kind of semantic unity? According to Davidson, the problem cannot be solved by assigning referents to predicates, since this leads to an infinite regress. Frege famously contributes the idea that predicates are “incomplete” or “unsaturated” functional expressions, mapping objects to truth-values. However, he takes predicates to refer to concepts and thus is exposed (...) to Davidson′s argument. I will show that Davidson is only right with regards to “Frege′s semantics”. Yet Frege′s logical doctrine of the decomposition of a sentence – I shall argue – allows for a resolution of this problem. (shrink)

This paper challenges a standard interpretation according to which Frege’s conception of logic (early and late) is at odds with the contemporary one, because on the latter’s view logic is formal, while on Frege’s view it is not, given that logic’s subject matter is reality’s most general features. I argue that Frege – in Begriffsschrift – retained the idea that logic is formal; Frege sees logic as providing the ‘logical cement’ that ties up together the contentful concepts of specific sciences, (...) not the most general truths. Finally, I discuss how Frege conceives of the application of Begriffsschrift, and of its status as a ‘lingua characteristica’. (shrink)

This talk surveys a range of positions on the fundamental metaphysical and epistemological questions about elementary logic, for example, as a starting point: what is the subject matter of logic—what makes its truths true? how do we come to know the truths of logic? A taxonomy is approached by beginning from well-known schools of thought in the philosophy of mathematics—Logicism, Intuitionism, Formalism, Realism—and sketching roughly corresponding views in the philosophy of logic. Kant, Mill, Frege, Wittgenstein, Carnap, Ayer, Quine, and Putnam (...) are among the philosophers considered along the way. (shrink)

Are Fregean thoughts compositionally complex and composed of senses? We argue that, in Begriffsschrift, Frege took 'conceptual contents' to be unstructured, but that he quickly moved away from this position, holding just two years later that conceptual contents divide of themselves into 'function' and 'argument'. This second position is shown to be unstable, however, by Frege's famous substitution puzzle. For Frege, the crucial question the puzzle raises is why "The Morning Star is a planet" and "The Evening Star is a (...) planet" have different contents, but his second position predicts that they should have the same content. Frege's response to this antinomy is of course to distinguish sense from reference, but what has not previously been noticed is that this response also requires thoughts to be compositionally complex, composed of senses. That, however, raises the question just how thoughts are composed from senses. We reconstruct a Fregean answer, one that turns on an insistence that this question must be understood as semantic rather than metaphysical. It is not a question about the intrinsic nature of residents of the third realm but a question about how thoughts are expressed by sentences. (shrink)

Frege’s famous definition of number famously uses the concept of “extension”. Extensions, in the Fregean framework, are susceptible to bringing many difficulties, and, some say, even paradoxes. Therefore, neo-logicist programs want to avoid the problems and to replace the classical Fregean definition of number with Hume’s Principle. I argue that this move, even if it makes sense from a computational point of view, is at odds with Frege’s larger philosophical project. For Frege, I claim, extensions were an important part of (...) his philosophical program of logic-as-an-universal-language. This is why Frege places his project in line with Leibniz’ philosophical project of finding a lingua characterica universalis. (shrink)

This paper addresses a number of closely related questions concerning Kant's model of intentionality, and his conceptions of unity and of magnitude [Gröβe]. These questions are important because they shed light on three issues which are central to the Critical system, and which connect directly to the recent analytic literature on perception: the issues are conceptualism, the status of the imagination, and perceptual atomism. In Section 1, I provide a sketch of the exegetical and philosophical problems raised by Kant's views (...) on these issues. I then develop, in Section 2, a detailed analysis of Kant's theory of perception as elaborated in both the Critique of Pure Reason and the Critique of Judgment; I show how this analysis provides a preliminary framework for resolving the difficulties raised in Section 1. In Section 3, I extend my analysis of Kant's position by considering a specific test case: the Axioms of Intuition. I contend that one way to make sense of Kant's argument is by juxtaposing it with Russell's response to Bradley's regress; I focus in particular on the concept of ‘unity’. Finally, I offer, in Section 4, a philosophical assessment of the position attributed to Kant in Sections 2 and 3. I argue that, while Kant's account has significant strengths, a number of key areas remain underdeveloped; I suggest that the phenomenological tradition may be read as attempting to fill precisely those gaps. (shrink)

The paper challenges a widely held interpretation of Frege's conception of logic on which the constituent clauses of basic law V have the same sense. I argue against this interpretation by first carefully looking at the development of Frege's thoughts in Grundlagen with respect to the status of abstraction principles. In doing so, I put forth a new interpretation of Grundlagen §64 and Frege's idea of ‘recarving of content’. I then argue that there is strong evidence in Grundgesetze that Frege (...) did not hold the relevant sense-identity claim regarding basic law V. (shrink)

The book presents the various theories of intentionality from Brentano and Husserl to present day (1997) theories on mental content, narrow and broad.

O presente manual tem como intenção constituir um guia para uma disciplina introdutória de filosofia da linguagem. Foi elaborado a partir da leccionação da disciplina de Filosofia da Linguagem I na Faculdade de Letras da Universidade do Porto desde 2001. A disciplina de Filosofia da Linguagem I ocupa um semestre lectivo e proporciona aos estudantes o primeiro contacto sistemático com a área da filosofia da linguagem. Pretende-se que este manual ofereça aos estudantes os instrumentos necessários não apenas para acompanhar uma (...) iniciação ao campo da filosofia da linguagem mas também para o estudo e a investigação autónomos posteriores. Para isso é percorrido um trajecto que conduz das intuições pré-teóricas acerca de linguagem, de que todos dispomos, até um conhecimento disciplinar específico, histórico e temático, da filosofia da linguagem. Em termos práticos, são considerados como precedentes da disciplina de Filosofia da Linguagem I – mesmo se, pelo existem actualmente precedências em sentido estrito – as disciplinas de Lógica I e II e de Filosofia do Conhecimento I e II. Os programas dessas disciplinas nos últimos anos estiveram presentes por trás da elaboração do manual. (shrink)

This paper explores the relationship between Hume's Prinicple and Basic Law V, investigating the question whether we really do need to suppose that, already in Die Grundlagen, Frege intended that HP should be justified by its derivation from Law V.

What is the relevance of the history of philosophy to philosophy as such? This is not the question, what is the reason for studying the history of philosophy? This question is easy to answer. Philosophy is part of our culture, and the history of our culture is worth studying, if anything is. Nor is it the question, should academic institutions teach the history of philosophy as part of a philosophical education? It is widely accepted that students should be taught the (...) history of philosophy, even if philosophy itself is not considered an essentially historical discipline. An education in the history of philosophy is part of a broadly humanistic university education, and something of value for this reason alone, without it being necessary for anyone who actually pursues philosophy creatively and systematically to have to take history into account. (shrink)

En su obra de 1884, Die Grundlagen der Arithmetik [Gl.], Frege establece el principio del contexto como uno de sus principios fundamentales y propone valerse de él para dar con el concepto adecuado de número. Así, ofrece una definición de tipo contextual de número cardinal, pero ante una objeción que le resulta insalvable se decide por una definición explicita. La cuestión acerca de cuál ha sido entonces el sentido de establecer con tanto énfasis el principio del contexto admite más de (...) una respuesta. Mi texto polemiza con la interpretación canónica que se ha dado al papel de este principio en Gl., acusándola de permanecer encandilada por lo que se lee de manera inmediata en desmedro de una evaluación más integral y crítica. En particular, defenderé que: i) a diferencia de lo afirmado en Dummett 1991, la definición contextual de número cardinal no es abandonada por Frege al dar su definición explícita de número, ii) el principio del contexto tiene en Gl. un papel erístico fundamental de eliminar posiciones rivales acerca de la naturaleza de los números, iii) dicha definición contextual de número tiene un papel heurístico en el contexto de descubrimiento, en el sentido de que ofrece una intuición clave que permite llegar a la formulación final, iv) a su vez, la definición contextual es una condición necesaria de la definición explícita en el contexto de justificación, siendo que esta última se ha construido a partir de la primera. Por todo ello, sostengo que la función del principio del contexto no es la que prioriza Dummett, i. e., la fallida función de resolver el problema ontológico de la naturaleza de los números, sino que es fundamentalmente metodológica. En efecto, es en su función erística y heurística en donde debe ubicarse su relevancia para la investigación llevada a cabo en Gl. In his masterpiece of 1884, Die Grundlagen der Arithmetik [Gl.] Frege presents the context principle as a fundamental one in his investigation à propos an accurate concept of number. Thus, resting on it he offers a contextual definition of cardinal number; but after analyzing some objections he realizes that this definition does not work and decides himself for an explicit one. The question about what is the purport of the context principle when something that appeared to be the consequence is put aside admits more than a single answer. In this paper I argue against the canonic interpretation for, even while keeping next to the Fregean text, it fails to offer an integral explanation of how the context principle works all along Gl. In particular, I will defend that: i) contrary with Dummett 1991, the contextual definition of cardinal number is not abandoned by Frege when giving his explicit definition of number, ii) the context principle has in Gl. a fundamental eristic role of crossing out rival positions about the nature of numbers, iii) such contextual definition of number has an heuristic role in the discovery context, in the sense it offers a key intuition towards the final formulation, iv) furthermore, the contextual definition is a necessary condition in the justification context for the latest has been built up through the first one. For all this, I maintain that the function of the context principle is not the one Dummett prioritizes, i. e., the failed function of solving the ontological problem of the nature of numbers; the function of the context principle is rather and fundamentally methodological. It is on its eristic and heuristic function that its relevance to the Gl. investigation must be looked for. (shrink)

This paper makes a Fregean analysis of certain expressions which, according to the way they are constructed, can refer, firstly, to events and, secondly, to the results of these events. This paper intends to show that –if we take into account the above mentioned expressions and use Fregean notions such as meaning, reference, function, argument and concept– it is possible to consider events as objects. To do this we need to articulate developments made both from a linguistic perspective and a (...) philosophical one. In this particular case, we take into account the Fregean ontology; we try to analyze ontologically the linguistic phenomena called nominalization and arrive to interesting conclusions about the ontological and semantic behavior of the expressions that contain event and result nominalizations. (shrink)

Je soutiens que la prise en compte de Lotze dans la genèse de la phénoménologie du jeune Husserl fournit de nouveaux éléments qui supportent la lecture frégéenne de la phénoménologie. Pour ce faire, je vais d’abord retracer l’origine lozéenne des questions épistémologiques issues du développement de la nouvelle psychologie et de la logique au milieu du XIXe siècle en Allemagne et j’insisterai sur l’apport de trois de ses étudiants prestigieux; je montrerai ensuite que Husserl a acquis sa connaissance de cette (...) problématique via sa fréquentation de Brentano et de Stumpf; je me pencherai ensuite sur la tournant antipsychologiste de Husserl au milieu des années 1890 et examinerai brièvement un manuscrit de Husserl intitulé « Microcosmos » qui date de cette même période et qui montre clairement l’apport de la logique de Lotze dans ce tournant antipsychologiste; j’examinerai enfin brièvement l’apport de Lotze dans la critique que Husserl adresse au psychologisme logique dans ses Prolégomènes. Je conclurai avec quelques remarques sur l’importance de Lotze dans la phénoménologie de Husserl après la publication des Recherches logiques. (shrink)