Logic is usually thought to concern itself only with features that sentences and arguments possess in virtue of their logical structures or forms. The logical form of a sentence or argument is determined by its syntactic or semantic structure and by the placement of certain expressions called “logical constants.”[1] Thus, for example, the sentences Every boy loves some girl. and Some boy loves every girl. are thought to differ in logical form, even though they share a common syntactic and semantic (...) structure, because they differ in the placement of the logical constants “every” and “some”. By contrast, the sentences Every girl loves some boy. and Every boy loves some girl. are thought to have the same logical form, because “girl” and “boy” are not logical constants. Thus, in order to settle questions about logical form, and ultimately about which arguments are logically valid and which sentences logically true, we must distinguish the “logical constants” of a language from its nonlogical expressions. (shrink)

The Principle of Sufficient Reason is a powerful and controversial philosophical principle stipulating that everything must have a reason or cause. This simple demand for thoroughgoing intelligibility yields some of the boldest and most challenging theses in the history of metaphysics and epistemology. In this entry we begin with explaining the Principle, and then turn to the history of the debates around it. A section on recent discussions of the Principle will be added in the near future.

We re-examine the problem of existential import by using classical predicate logic. Our problem is: How to distribute the existential import among the quantified propositions in order for all the relations of the logical square to be valid? After defining existential import and scrutinizing the available solutions, we distinguish between three possible cases: explicit import, implicit non-import, explicit negative import and formalize the propositions accordingly. Then, we examine the 16 combinations between the 8 propositions having the first two kinds of (...) import, the third one being trivial and rule out the squares where at least one relation does not hold. This leads to the following results: (1) three squares are valid when the domain is non-empty; (2) one of them is valid even in the empty domain: the square can thus be saved in arbitrary domains and (3) the aforementioned eight propositions give rise to a cube, which contains two more (non-classical) valid squares and several hexagons. A classical solution to the problem of existential import is thus possible, without resorting to deviant systems and merely relying upon the symbolism of First-order Logic (FOL). Aristotle’s system appears then as a fragment of a broader system which can be developed by using FOL. (shrink)

Leibniz's principle of sufficient reason (PSR) is the claim that everything has a sufficient reason. But is Leibniz committed to the necessity or to the contingency of his great principle? I argue that Leibniz is committed to its contingency, given that he allows for the absolute possibility of entities that he claims violate the PSR. These are all cases of qualitatively indiscernible entities, such as indiscernible atoms, vacua, and bodies. However, Leibniz's commitment to the contingency of the PSR seems to (...) stand in tension with his inference of the PSR from his theory of truth. I argue that this apparent tension can be resolved satisfactorily. When it comes to his modal views on the PSR, Leibniz's position is entirely consistent. (shrink)

This article reconstructs Henri Bergson’s argument at the beginning of the second chapter of his Essai sur les données immédiates de la conscience for his view that every idea of number involves sp...

Descartes's general rule that “whatever is clearly and distinctly perceived is true” has traditionally been criticized on two closely related grounds. As Leibniz, for example, puts it, clearness and distinctness are of no value as criteria of truth unless we have criteria of clearness and distinctness; but Descartes gives none. And consequently, the standards of judgment which the rule in fact evokes are purely subjective and psychological. There must hence be set up analytic, logical “marks” by means of which it (...) can infallibly and without arbitrariness be recognized whether any ideas or propositions are or are not clear and distinct. (shrink)

Seventeenth century discussions of materialism, whether favorable or hostile towards the position, are generally conducted on a level of much less precision and sophistication than recent work on the problem of the mind-body relation. Nevertheless, the earlier discussions can still be interesting to philosophers, as the plethora of references to Cartesian arguments in the recent literature makes clear. Certainly the early development of materialist patterns of thought, and efforts on both the materialist and immaterialist side to establish fundamental points in (...) the philosophical analysis of mind, have considerable historical interest at the present time. This paper attempts to clarify the significance of some of leibniz's views in connection with the materialist thesis. I do not have in mind his rather notorious parallelism, though some of the points made below bear indirectly on the character of this position. Instead, I will examine his approach to arguments against materialism. (shrink)

From the mid-1600s to the beginning of the eighteenth century, there were two main circles of German scholars which focused extensively on diagrammatic reasoning and representation in logic. The first circle was formed around Erhard Weigel in Jena and consists primarily of Johann Christoph Sturm and Gottfried Wilhelm Leibniz; the second circle developed around Christian Weise in Zittau, with the support of his students, particularly Samuel Grosser and Johann Christian Lange. Each of these scholars developed an original form of using (...) geometric diagrams in logic. In this paper, I will trace the historical notes of John Venn and other modern logicians back to the original works published in the Weigel and Weise circles and describe the development of using geometric figures for logical reasoning and representation in that period of time. (shrink)

After recalling the distinction between logic as reasoning and logic as theory of reasoning, we first examine the question of relativity of logic arguing that the theory of reasoning as any other science is relative. In a second part we discuss the emergence of universal logic as a general theory of logical systems, making comparison with universal algebra and the project of mathesis universalis. In a third part we critically present three lines of research connected to universal logic: logical pluralism, (...) non-classical logics and cognitive science. (shrink)

The aim of the paper is to illuminate some core aspects of Leibniz’s conception of judgement and its place in his conception of the mind. In particular, the paper argues for three claims: First, the act of judgement is at the centre of Leibniz’s conception of the mind in that minds strive at actualising innate knowledge concerning derivative truths, where the actualising involves an act of judgement. Second, Leibniz does not hold a judgement account of predication, but a two-component account (...) that distinguishes between predication and alethic evaluation. Third, Leibniz understands the act of affirmative judgement in terms of establishing active dispositions, i.e. strivings, to make reasons available for future reasoning that aims at answering whether-questions. Correspondingly, he understands the act of negative judgement in terms of establishing dispositions to ban propositions from future reasoning that aims at answering whether-questions. In the final analysis, the acts of affirmative as well as of negative judgement turn out to be acts of changing memory dispositions. (shrink)

Barry Smith recently discussed the diagraphs of book eight of Jacob Lorhard’s Ogdoas scholastica under the heading “birth of ontology” (Smith, 2022; this issue). Here, I highlight the commonalities between the original usage of diagraphs in the tradition of Ramus for didactic purposes and the the usage of their present-day successors–modern ontologies–for computational purposes. The modern ideas of ontology and of the universal computer were born just two generations apart in the breakthrough century of instrumental reason.

In this article we expand upon the conceptual framework of Félix Guattari’s 1989 essay, The Three Ecologies. Here Guattari examines changes in subjectivity that have come about due to scientific and technological advances which, as he sees it, brought about an “ecological disequilibrium” ([1989]2000, 27) and deteriorated individual and collective modes of being. In response to this Guattari proposes a kind of holistic therapy or ‘ecosophy’ between three ecological registers: “the environment, social relations and human subjectivity” (ibid., 28). Guattari cautions (...) that we not only take note of these macro determinations, but also heed the libidinal impulses of desire – what captures it, what directs it, and what shuts it down. Since the publication of The Three Ecologies, the rise of digital technologies has dramatically influenced the ways in which people think, live and communicate. Technological infrastructures, for instance, are used to spread disinformation at a vast speed and scale, and because social networks are often homophile many people infrequently encounter critical disagreement and debate. The increase in media and digital communications usage has also led to new forms of social inclusion and exclusion, the most exacerbated form of which is probably the phenomenon known as hikikomori – acute, prolonged social withdrawal. Taking hikikomori as our focus, we describe what we see as a general set of symptoms of society and trace its myriad intersections with an ever-increasing algorithmic ubiquity, which we posit as the new form of hyper-modulation following from Foucault’s disciplinary societies and Deleuze’s control societies. (shrink)

Gottfried Wilhelm Leibniz (1646–1716) was one of the great thinkers of the seventeenth and eighteenth centuries and is known as the last “universal genius”. He made deep and important contributions to the fields of metaphysics, epistemology, logic, philosophy of religion, as well as mathematics, physics, geology, jurisprudence, and history. Even the eighteenth century French atheist and materialist Denis Diderot, whose views could not have stood in greater opposition to those of Leibniz, could not help being awed by his achievement, writing (...) in his Encyclopedia, “Perhaps never has a man read as much, studied as much, meditated more, and written more than Leibniz… What he has composed on the world, God, nature, and the soul is of the most sublime eloquence. If his ideas had been expressed with the flair of Plato, the philosopher of Leipzig would cede nothing to the philosopher of Athens.” (Vol. 9, p. 379) Indeed, Diderot's mood was almost despairing in a remark from another piece, which also has a great deal of truth in it: “When one compares the talents one has with those of a Leibniz, one is tempted to throw away one's books and go die quietly in the dark of some forgotten corner.” More than a century later, Gottlob Frege, who fortunately did not cast his books away in despair, expressed similar admiration, declaring that “in his writings, Leibniz threw out such a profusion of seeds of ideas that in this respect he is virtually in a class of his own.” (“Boole's logical Calculus and the Concept script” in Posthumous Writings , p. 9) The aim of this entry is primarily to introduce Leibniz's life and summarize and explicate his views in the realms of metaphysics, epistemology, philosophical theology, and natural philosophy. (shrink)

Leibniz’s universal characteristic is a fundamental aspect of his theory of cognition. Without symbols or characters it would be difficult for the human mind to define several concepts and to achieve many demonstrations. In most disciplines, and particularly in mathematics, the mind must then focus on symbols and their combinatorial rules rather than on mental contents. For Leibniz, mental perception is most of the time too confused for attaining distinct notions and valid deductions. In this paper, I argue that the (...) functions of symbolization differ depending upon the kind of concepts that are replaced with characters. In my view, most commentators did not sufficiently underline the distinction between two main functions of formal substitution in Leibniz’s characteristic: either increasing our knowledge or simply structuring it. In the first case, we complete our knowledge because formal substitution makes sensible and imaginary concepts more distinct. In the second case, symbolization helps to organize contents that are already conceived of by reason. Thus the process of substitution is not always identically applicable, for symbols replace different types of concepts. (shrink)

TheGenerales Inquisitiones de Analysi Notionum et Veritatumis Leibniz’s most substantive work in the area of logic. Leibniz’s central aim in this treatise is to develop a symbolic calculus of terms that is capable of underwriting all valid modes of syllogistic and propositional reasoning. The present paper provides a systematic reconstruction of the calculus developed by Leibniz in theGenerales Inquisitiones. We investigate the most significant logical features of this calculus and prove that it is both sound and complete with respect to (...) a simple class of enriched Boolean algebras which we call auto-Boolean algebras. Moreover, we show that Leibniz’s calculus can reproduce all the laws of classical propositional logic, thus allowing Leibniz to achieve his goal of reducing propositional reasoning to algebraic reasoning about terms. (shrink)

Leibniz had a well-known argument against the existence of infinite wholes that is based on the part-whole axiom: the whole is greater than the part. The refutation of this argument by Russell and others is equally well known. In this note, I argue (against positions recently defended by Arthur, Breger, and Brown) for the following three claims: (1) Leibniz himself had all the means to devise and accept this refutation; (2) This refutation does not presuppose the consistency of Cantorian set (...) theory; (3) This refutation does not cast doubt on the part-whole axiom. Hence, should there be an obstacle to Gödel's wish to integrate Cantorian set theory within Leibniz' philosophy, it will not be this famous argument of Leibniz'. (shrink)

In various arguments, Descartes relies on the principles that conceivability implies possibility and that inconceivability implies impossibility. Those principles are in tension with another Cartesian view about the source of modality, i.e. the doctrine of the free creation of eternal truths. In this paper, I develop a ‘two-modality’ interpretation of the doctrine of eternal truths which resolves the tension and I discuss how the resulting modal epistemology can still be relevant for the contemporary discussion.

The vision of machines autonomously carrying out substantive conjecture generation, theorem discovery, proof discovery, and proof verification in mathematics and the natural sciences has a long history that reaches back before the development of automatic systems designed for such processes. While there has been considerable progress in proof verification in the formal sciences, for instance the Mizar project’ and the four-color theorem, now machine verified, there has been scant such work carried out in the realm of the natural sciences—until recently. (...) The delay in the case of the natural sciences can be attributed to both a lack of formal analysis of the so-called “theories” in such sciences, and the lack of sufficient progress in automated theorem proving. While the lack of analysis is probably due to an inclination toward informality and empiricism on the part of nearly all of the relevant scientists, the lack of progress is to be expected, given the computational hardness of automated theorem proving; after all, theoremhood in even first-order logic is Turing-undecidable. We give in the present short paper a compressed report on our building upon these formal theories using logic-based AI in order to achieve, in relativity, both machine proof discovery and proof verification, for theorems previously established by humans. Our report is intended to serve as a springboard to machine-produced results in the future that have not been obtained by humans. (shrink)

This essay is an attempt to offer at least a partial answer to the question concerning Leibniz's motivation for the need to create a universal language. It is relevant, among other things, due to Leibniz's claim which contradicts the idea of a universal language, in which he clearly stresses that “every language, even the poorest one, can express everything”, as well as owing to Leibniz's historical contribution to the idea of formalization and to the mechanization of the reasoning processes. This (...) paper is also an attempt to reconstruct the paradigm of language research pursued in a specific period of time in 17th century language theory. (shrink)

Leibniz is unclear about the nature of pleasure. In some texts, he describes pleasure as a perception of perfection, while in other texts he describes pleasure as being caused by a perception of perfection. In this article, I disambiguate two senses of “perception of perfection”, which clarifies Leibniz’s considered position. I argue that pleasure is a perception of an increase in a substance’s power which is caused by a substance’s knowledge of a perfection of the universe or God. This reading (...) helps clarify the nature of Leibnizian happiness. Happiness is a cognitive process (akin to a mood), constituted fundamentally out of pleasure, which is grounded in increases in a substance’s power. A rational substance will sustain its happiness so long as it is more powerful than it is weak, and it is engaging in activities that increase its power. (shrink)

In this paper, we consider what is commonly referred to as Leibniz’s argument for primitive concepts. After presenting and criticizing (in sections 1 and 2) one recent rather straightforward way of interpreting this argument, by Paul Lodge and Stephen Puryear, which takes the argument to be merely about the structure of concepts, we offer an alternative way of looking at the argument. We think it is best seen as being fundamentally about the relation between thought and reality. In order to (...) prepare the ground for our reconstruction (which we present in section 5), we have to introduce his view of ideas or concepts (section 3), as well as some metaphysical principles concerning reality-dependence (section 4). (shrink)

New light is shed on Leibniz’s commitment to the metaphysical priority of the intensional interpretation of logic by considering the arithmetical and graphical representations of syllogistic inference that Leibniz studied. Crucial to understanding this connection is the idea that concepts can be intensionally represented in terms of properties of geometric extension, though significantly not the simple geometric property of part-whole inclusion. I go on to provide an explanation for how Leibniz could maintain the metaphysical priority of the intensional interpretation while (...) holding that logically the intensional and the extensional stand in strictly inverse relation to each other. (shrink)

The aim of this paper is to understand why empiricist philosophers of language did not try to refute the Leibniz-Beauzée argument, which questioned the genetical priority of proper names. It is shown that, within the semantic theory which underlies the empiricist doctrine, one may assume that all general terms derive from particular names, while conceding that every proper name can be etymologically traced back to the ancestor of a common noun.

Leibniz's overall view of the relationship between reasoning and computation is discussed on the basis of two broad claims that one finds in his writings, concerning respectively the nature of human reasoning and the possibility of replacing human thinking by a mechanical procedure. A joint examination of these claims enables one to appreciate the wide scope of Leibniz's interests for mechanical procedures, concerning a variety of philosophical themes further developed both in later logical investigations and in methodological contributions to cognitive (...) psychology. (shrink)

Hahmottelen tässä artikkelissa tekoälyn historiaa varhaismodernin filosofian aikakaudella 1600–1700-luvuilla. Esittelemäni aiheet ovat hieman erillisiä toisistaan, mutta yhteistä niille on ajatus komputaatiosta tai automaatiosta, eräänlaisesta mekaanisesta laskemisesta tai toiminnasta, jota voi pitää tekoälyn varhaisena lähtökohtana. -/- On kuitenkin huomattava, että pelkkä komputaatio eli informaation käsittely sinänsä ei riitä tekoälylle – kaikkia näitä pyrkimyksiä leimaa tietynlainen epistemologinen optimismi: automatisoidun ajattelun avulla uskotaan saatavan enemmän laadukasta tietoa ja kenties myös uudenlaisia ajatuksia, kun ajatteluprosessi tulee sujuvammaksi. Tekoälyn varhaishistoria liittyy siis nimenomaan inhimillisen ajattelun mekanisoimiseen (...) ja uskoon siitä, että sen avulla voidaan lieventää ihmismielen rajoituksia ja ajatella paremmin. Yhteistä sekä tekoälyn että tietokoneen historialle on kuitenkin laskennan kehitys. (shrink)

Not unlike many contemporary philosophers, Leibniz admitted the existence of temporary truths, true propositions that have not always been or will not always be true. In contrast with contemporary philosophers, though, Leibniz conceived of truth in terms of analytic containment: on his view, the truth of a predicative sentence consists in the analytic containment of the concept expressed by the predicate in the concept expressed by the subject. Given that analytic relations among concepts are eternal and unchanging, the problem arises (...) of explaining how Leibniz reconciled one commitment with the other: how can truth be temporary, if concept-containment is not? This paper presents a new approach to this problem, based on the idea that a concept can be consistent at one time and inconsistent at another. It is argued that, given a proper understanding of what it is for a concept to be consistent, this idea is not as problematic as it may seem at first, and is in fact implied by Leibniz’s general views about propositions, in conjunction with the thesis that some propositions are only temporarily true. (shrink)

Leibniz frequently argued that reasons are to be weighed against each other as in a pair of scales, as Professor Marcelo Dascal has shown in his article "The Balance of Reason." In this kind of weighing it is not necessary to reach demonstrative certainty – one need only judge whether the reasons weigh more on behalf of one or the other option However, a different kind of account about rational decision-making can be found in some of Leibniz's writings. In his (...) article "Was Leibniz's Deity an Akrates?" Professor Jaakko Hintikka has argued that Leibniz developed a new vectorial model for rational decisions which is better suited to complicated decisions, where values are complementary to each other. This model, related closely to his work in metaphysics and the philosophy of mind, is a heuristic device which helps in finding rational combinations - and in an ideal case an optimum - between plural inclinations to the good. I shall argue that Leibniz applies more or less implicitly both of these models in his practical rationality. In simple situations he applied the pair of scales model and in more complicated situations he applied the vectorial model. (shrink)

ABSTRACT This paper is an analysis of the manner Nishida Kitarô, in the process of construction of his own philosophy of religion, enters into dialogue with Leibniz's thought concerning Pre-established Harmony. Although the philosophy of religion is an important theme and Nishida goes back to Leibniz at some points in his textual career, there are relatively few studies that touch on the relationship between these two thinkers. I study Nishida's approach under three headings. The first section concerns ten main aspects (...) of the world of pre-established harmony. The second tries to show the manner in which such a world becomes a guide towards a philosophy of religion, placing the emphasis on three characteristically Christian aspects: a created, fallen, and Trinitarian world. The third section includes some elements such as the entrance into religion, metanoia, satori and a comparison between Christian agape and Buddhist maha-kruna. These are themes on which Nishida elaborates in his 1945 masterpiece, The Logic of Basho and a Religious Worldview. RESUMO Este trabalho é uma análise da forma pela qual Nishida Kitarô, no processo de construção de sua própria filosofia da religião, entra em diálogo com o pensamento de Leibniz relativo à Harmonia Pré-Estabelecida. Embora a filosofia da religião seja um tema importante, e Nishida retome Leibniz em alguns pontos em sua carreira textual, existem relativamente poucos estudos que abordem a relação entre esses dois pensadores. Estudo a abordagem de Nishida sob três categorias. A primeira seção refere-se a dez principais aspectos do mundo de harmonia preestabelecida. A segunda busca demonstrar o modo pelo qual esse mundo se torna um guia para uma filosofia da religião, colocando a ênfase em três aspectos caracteristicamente cristãos: um mundo criado, caído e trinitário. A terceira seção inclui alguns elementos, tais como a entrada na religião, a metanoia, o satori e uma comparação entre o Ágape cristão e o Maha-Kruna budista. Estes são temas sobre os quais Nishida elabora em sua obra-prima de 1945, A Lógica de Basho e uma Visão Religiosa do Mundo. (shrink)

This article offers a reconstruction of Derrida’s critique of Leibniz. It suggests that in attempting to fit Leibniz into his conception of the history of metaphysics and the all-embracing notion of logocentrism that underwrites it, Derrida presupposes two regimes of logocentrism: one subjective, the other theological. Subsumed into this second mode, Derrida casts Leibniz as a progenitor of structuralism and the new sciences and technologies of information in order to expose their logocentric foundations. However, in doing so, he ends up (...) sidelining the aspect of Leibniz’s ideas that anticipates the specificity of the new epoch of writing he claims to historicise. The article goes on to argue that to grasp this specificity one must look beyond the “expressivist” schema of exterior representation, which Derrida draws from Husserl’s theory of meaning, and instead look to Leibniz’s own formal-combinatorial concept of expression, which exceeds Derrida’s critical framework. (shrink)

I examine several alleged grounds of the principle of sufficient reason in Leibniz’s philosophy. These include the nature of a requisite and a sufficient condition, the nature of truth, and the nature of harmony. I argue that Leibniz does not ground the PSR in any of these ways. Instead, he is committed to a value-based grounds of the PSR: God creates the best possible world, and the fact that the PSR obtains in this world contributes to it being the best. (...) I conclude by considering some objections to this way of grounding the PSR. (shrink)

Leibniz had a well-known argument against the existence of infinite wholes that is based on the part-whole axiom: the whole is greater than the part. The refutation of this argument by Russell and others is equally well known. In this note, I argue (against positions recently defended by Arthur, Breger, and Brown) for the following three claims: (1) Leibniz himself had all the means to devise and accept this refutation; (2) This refutation does not presuppose the consistency of Cantorian set (...) theory; (3) This refutation does not cast doubt on the part-whole axiom. Hence, should there be an obstacle to Gödel's wish to integrate Cantorian set theory within Leibniz' philosophy, it will not be this famous argument of Leibniz'. (shrink)

The paper provides an alternative interpretation of ‘pair points’, discussed in Beall et al., "On the ternary relation and conditionality", J. of Philosophical Logic 41(3), 595-612. Pair points are seen as points viewed from two different ‘perspectives’ and the latter are explicated in terms of two independent valuations. The interpretation is developed into a semantics using pairs of Kripke models (‘pair models’). It is demonstrated that, if certain conditions are fulfilled, pair models are validity-preserving copies of positive substructural models. This (...) yields a general soundness and completeness result for a variety of (positive) substructural logics with respect to multimodal Kripke frames with binary accessibility relations. In addition, an epistemic interpretation of pair models is provided. (shrink)

Deleuze's Postscript on the Societies of Control has been the most common entry point for interrogating the ways in which contemporary digital technologies have altered the social and the subjective from a Deleuzo-Guattarian perspective. It is, however, in A Thousand Plateaus that we find the most comprehensive set of resources for grappling with the Algocene, the contemporary digitally interconnected world of ubiquitous computing, drones, data mining, smart cities, social media, automated trading and other data-driven technologies that are heavily reliant upon (...) algorithmic processes and deep learning networks. In this broad survey, I argue that in order to grapple with these new technological assemblages and the implications of their deployment across society, we should posit a new major stratum, the algoplastic, and, along with it, new modes of operation of order-words and the regimes of signs they form part of. I conclude by posing some of the new problems that emerge with the Algocene. (shrink)

O principal objetivo deste artigo é mostrar, contra as interpretações da filosofia de Leibniz que tendem a reduzir sua noção de substância a uma concepção derivada unicamente de considerações de natureza lógica, que o conceito leibniziano de substância possui raízes lógicas, físicas e teológicas que são mutuamente independentes.

When Bouvet discovered the relationship between the binary arithmetic of Leibniz and the hexagrams of the I ching—in reality only a purely formal correspondence—he sent to Leibniz a woodcut diagram of the Fu-Hsi arrangement, which provides the key to the analogy. This diagram, in a re-drawn version, was first published by Gorai Kinzō in a study of Leibniz's interpretation of the I ching and Confucianism which has been influential in providing, indirectly, the principal source for the accounts of Wilhelm and (...) Needham. Yet this pioneering study of Leibniz's interpretation of the hexagrams is virtually unknown. Even the account of Needham, who saved it from complete obscurity, contains one or two inaccuracies about it and these are repeated by Zacher in his otherwise excellent monograph on Leibniz's binary arithmetic. (shrink)

L'idée d'associer probabilité et induction n'est pas propre au xxe siècle, mais elle a reçu un développement systématique lorsque les philosophes néo-positivistes s'en sont emparés. Dès les années 1940, le philosophe Rudolf Carnap s'est proposé de relever le «défi humien» en fondant une théorie de la confirmation par la construction d'une logique probabiliste dite «inductive». Ce projet avait été esquissé à Cambridge dans les années 1920 par l'économiste John M. Keynes. Examiner le programme de Carnap dans sa totalité, le situer (...) dans son contexte historique, suivre son évolution et les influences qu'il a eues, tels sont les buts de cet article. The idea of associating probability and induction is not a theme suitable for the xxth century but it has received a systematic development when the neo-positivist philosophers seized it. Beginning with the 1940's, the philosopher Rudolph Carnap proposed to affront the «Humian challenge» by founding a theory of confirmation through the construction of a probabilistic logic called «inductive». This project had been outlined in Cambridge during the 1920's by the economist John M. Keynes. To examine Carnap's program in its totality, to situate it in its historical context, to follow its evolution and the influences it has had, these are the aims of this article. (shrink)

This volume presents recent advances in philosophical logic with chapters focusing on non-classical logics, including paraconsistent logics, substructural logics, modal logics of agency and other modal logics. The authors cover themes such as the knowability paradox, tableaux and sequent calculi, natural deduction, definite descriptions, identity, truth, dialetheism and possible worlds semantics. The developments presented here focus on challenging problems in the specification of fundamental philosophical notions, as well as presenting new techniques and tools, thereby contributing to the development of the (...) field. Each chapter contains a bibliography, to assist the reader in making connections in the specific areas covered. Thus this work provides both a starting point for further investigations into philosophical logic and an update on advances, techniques and applications in a dynamic field. The chapters originate from papers presented during the Trends in Logic XI conference at the Ruhr University Bochum, June 2012. (shrink)

Resumo:É pretendido, neste pequeno texto, mostrar como Leibniz se insere de modo bem peculiar na tradicional discussão filosófica acerca da liberdade do agente num mundo governado pelo princípio de razão suficiente. A questão posta por Arnauld, em carta de 13 de março de 1686, além de forçar Leibniz a dar esclarecimentos sobre a solução que adotou, também é importante por carregar certos resquícios do modo pelo qual Aristóteles abordou este tema. Também deve ser notado que, apesar da ruptura que a (...) solução leibniziana faz com a tradição aristotélica, vários outros pontos da filosofia de Aristóteles são aceitos para a construção e resolução do problema. (shrink)

This paper is a survey of Father Mersenne’s views about the classification of sciences, its reasons and its practical consequences. Some emphasis is put on the interconnection between Mersenne’s two majors ideas about the practice of science : scientific research is an activity mostly devoted to religious apology and to the edification of the people. This religious concern allows him to resist two of the most influential philosophical streams of his time, scepticism and alchemy, which provide some favorite opponents to (...) his works. We also show how an analogical kinship based on theological considerations and on the classification of sciences gives ground to the same kind of arguments shaping his views about arithmetic, language, and music. Finally, we focus on the connection between Mersenne’s theses, especially about the nature and virtue of language and sound, and a more general discussion of the scientific status of music and language in the context of the blooming of academies. (shrink)

O trabalho pretende abordar as relações entre a doutrina coerentista da verdade tal como concebida por Leibniz e os limites que esta aparentemente impõe à possibilidade de se dizerem contingentes os eventos que têm lugar no universo e o próprio mundo enquanto sistema geral de fenômenos. Nosso principal objetivo será analisar como é possível compatibilizar esses dois aspectos capitais da filosofia leibniziana a partir da teoria da expressão, uma vez que precisamente nesta teoria reside a principal condição de constituição das (...) noções completas às quais inerem os acontecimentos, e, por conseguinte, o mundo. Com efeito, muito embora seja tributária da concepção de verdade como inclusão, a teoria dos conceitos individuais completos não se deixa explicar exaustivamente pela doutrina coerentista, uma vez que a própria completude de tais conceitos depende de sua pertença a um conjunto de compossíveis em relação aos quais mantém uma série de relações de expressão. E é precisamente dessas relações de entre-expressão que acreditamos derivar a infinidade de circunstâncias integrantes das noções individuais, as quais tornam esses seres inexplicáveis em termos estritamente lógicos, e as quais, portanto, são a raiz da natureza contingente da maior parte das predicações relativas a indivíduos. (shrink)

The ArgumentThe secret of invention or the art of inventing has recently become the object of positive or experimental research, aimed at discovering the logic of the initial mental processes that lead to “innovation.” But the problem is old and goes back to antiquity: The art of memory, rhetoric, symbolics. Does the succession of thought in invention follow a rule, such that its variations could be classified? Here I offer but a general direction: There is an analogy between the two (...) relations: invention/innovation and fecundation/maturation – namely, a male and a female principle.The Ancients thought that inventing was a divine art and that man receives the spark to then brood over its fruit in his mind. Today's still dominant materialist tendency insists on the importance of this secondary maturation and minimizes the role of the primordial spark.Thus becomes possible the ranking according to a unique order — but not without hesitations and guilt — of thinkers as far apart as Mandeville, Adam Smith, Hegel, Buffon, Rousseau, and Herder, to find the contemporary trend to which François Dagognet belongs. (shrink)

Apresento e desenvolvo neste artigo o problema da prova sortuda, analisando duas soluções para ele presentes na literatura. A primeira delas consistira em alegar que mostrar que o predicado está contido no sujeito não basta como demonstração da verdade de uma proposição, sendo preciso que se prove ainda que a noção relativa ao sujeito é logicamente consistente. A segunda repousaria em uma hierarquização modal, por assim dizer, dos pre- dicados integrantes de uma noção individual. Após exibir as razões que me (...) levam a rejeitar essas duas soluções, apresento os traços fundamentais de uma interpretação que me parece resolver o problema de maneira satisfatória. Minha posição envolve conceder ao Princípio da Razão Suficiente um papel central na compreensão do que significa, para Leibniz, provar que um determinado predicado está contido na noção relativa a um certo indivíduo. (shrink)

This article provides a thorough introduction into the problem arising in Leibniz’s philosophical system of whether God’s act of will in creation is rendered necessary following the system’s doctrine of truth and Principle of the Best. Several items necessary for a grasp of the subject are discussed first in summary fashion: §1 relevant elements of Leibniz’s logic and the nature of truth, §2 the meaning of freedom, and §3 the principle of perfection, or the best. In the final section, the (...) author defends the view that Leibniz effectively responds, within the framework of his logic, to the main objections against his position. It is argued that Leibniz is able to vindicate the system’s position on the freedom of God’s act of will in creating the order of nature, whereby the ‘root of contingency’ in his system is at once derived from God’s will and yet completely intelligible through the system’s modern Rationalism, logic and doctrine of truth. (shrink)