Leibniz: Epistemology

The causal theory, by J. Locke.--Phenomenalism, by G. Berkeley.--Skepticism, by D. Hume.--Traditional rationalism, by G. W. Leibniz.--Critical rationalism, by I. Kant.--Empiricism, by C. I. Lewis.--The quest for certainty, by R. Descartes.--Knowing and believing, by H. A. Prichard.--The right to be sure, by A. J. Ayer.

The aim of this paper is to connect Leibniz’s and Toulmin’s conceptions about practical and deliberative rationality. When trying to rationally justify contingent judgments Leibniz, like Toulmin, defends a weighing argumentative method. Thus, in Leibniz we can discern the balance between the legitimate demands of formal models of rationality and the lessons of a practice “situated” on a historical, social, and evaluative context.

In diesem Aufsatz möchten wir Leibniz' abwägende und gewichtende Methoden als fruchtbare Annäherung an das Kontingente, das durch Debatten, Kontroversen und letztlich normative Konflikte bestimmte Universum der menschlichen Praxis betrachten. Dieser Ansatz ergänzt Leibniz' bekanntes algorithmisches Verfahren und ist der Jurisprudenz verpflichtet – Leibniz wandte ihn selbst auf viele theoretische wie praktische Unternehmen an (Rechtsfragen, Religionsstreitigkeiten, Theodizee, ethische und politische Fragestellungen etc.). Leibniz' Inanspruchnahme einer Balance der Gründe und sein hiermit verbundenes metaphysisches Prinzip der Kontinuität nehmen zudem in mancher Hinsicht (...) die , Ausweitung' der Logik im gradualistischen Sinne voraus. (shrink)

In this paper, I examine Leibniz’s account of the epistemic status of the Christian Mysteries in his “Preliminary Dissertation on the Conformity of Faith with Reason.” In it, the Mysteries are held to be true, yet also to be beyond human comprehension. This conjunction gives rise to a dilemma: how can the Mysteries bemeaningfully asserted if they are unintelligible? To answer this, Leibniz compares them to natural truths, which are demonstrable by God alone. To complicate matters, however, he suggests that (...) certain Mysteries have the status of truths of logic, or of mathematics; this raises a special problem in understanding his view of the epistemic status of such Mysteries for us. I offer a suggestion as to how he may have wanted us to think of the relationship between these Mysteries and our faculty of comprehension. I then employ my conclusions in explaining Leibniz’s answer to Bayle’s skepticism regarding the Mysteries, as well as in explaining his answer to the question as to how belief in the Mysteries can be rationally justified. (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)

The Christian mysteries, which consist of such doctrines as the Incarnation and the Trinity, pose a problem for anyone who seeks to reconcile the tenets of Christianity with reason. As Leibniz puts it, the mysteries are incomprehensible, improbable, and against appearances. Why should a reasonable individual believe in such mysteries? By answering this question, one responds to the objection that Christianity requires individuals to embrace patent nonsense. Leibniz maintains that the mysteries, although incomprehensible, can be explained sufficiently to justify belief (...) in them. But how can the mysteries be both incomprehensible and explicable? In this paper, I will develop a Leibnizian account of why belief in the mysteries is justified. (shrink)

In Göttliche Gedanken (Godly Thoughts), Andreas Schmidt provides an in-depth discussion of the metaphysics of knowledge and of mind in four early-modern rationalists: Descartes, Malebranche, Spinoza, and Leibniz. His topic overlaps with what is called “philosophy of mind” in contemporary Anglo-American circles, for he is quite interested in the relation between mind and body in these four historical thinkers. But as Schmidt effectively reminds us, the “mind-body problem” looks entirely different when embedded in the conceptual setting of the seventeenth century. (...) In Schmidt’s reading, reflection on mind at that time begins with reflection on knowledge and our capacity to know. What must the mind be in order for us .. (shrink)

This article explores the grounds which Leibniz might have offered for his theory that all truths are analytic, by considering the reasons his predecessors seem to have had for advancing similar formulas. I take Descartes and Spinoza to be the predecessors who came closest to Leibniz's theory. In spite of Leibniz's own indications to the contrary, his theory seems to be fundamentally opposed to Aristotelian theories of truth. I suggest that Descartes, Spinoza and Leibniz were inclined toward this kind of (...) theory largely because they needed a theory which would explain how a sentence might be true even if it was about things which do not exist, as mathematical truths sometimes are. (shrink)

CHAPTER The principle of continuity and the 'paradox' of Leibnizian mathematics* Michel Serfati. Introduction On the basis of the epistemological analysis ...

The comparative study of Islamic philosophical views to those of contemporary philosophers calls for careful consideration of their opinions.This is because the similarities are apparent but the purport of what they say is quite different. Yet, the apparent similarities should not be thoroughly ignored and one can perhaps say that Leibniz's theory of perception and apperception is epistemologically close to the Sadrean theory of conceptual and judgmental knowledge. At least one can say that although Leibniz belongs to the tradition of (...) Modern Western Philosophy, his theory concerning the relationship between being and knowledge stands somewhere in the midpoint between Mulla Sadra and Berkley.Berkely has stated that to be is to be perceived and Mulla Sadra regards Knowledge as Being.In other words, in the eyes of the Scottish philosopher, existence is the same as perception and our philosopher has argued that perception is existence. Even if Leibniz may. in reality be closer to Berkley than Mulla Sadra but in view of the fact that knowledge is a constituent of Leibniz's monads and knowledge has different grades according to him, it is as if he would corroborate Sadra's theory concerning the unity of being and knowledge. (shrink)

Leibniz’s De incerti aestimatione, which contains his solution to the division problem, has not received much attention, let alone much appreciation. This is surprising because it is in this work that the definition of probability in terms of equally possible cases appears for the first time. The division problem is used to establish and test probability theory; it can be stated as follows: if two players agree to play a game in which one has to win a certain number of (...) rounds in order to win the pool, but if they break the game off before either of them has won the required number of rounds, how should the pool be distributed?Our article has two aims: it provides the readers with the first published English translation of De incerti aestimatione, and it also gives them a brief commentary that explains Leibniz’s philosophical and mathematical concepts necessary in order to understand this work. The translation is as literal as possible throughout; it shows how Leibniz struggled at times to find a solution to the division problem and how he approached it from different angles. The commentary discusses Leibniz’s views on four key concepts: fairness, hope, authority and possibility. The commentary then outlines how Leibniz attempted to solve the problem of division. (shrink)

Leibniz’s De incerti aestimatione, which contains his solution to the division problem, has not received much attention, let alone much appreciation. This is surprising because it is in this work that the definition of probability in terms of equally possible cases appears for the first time. The division problem is used to establish and test probability theory; it can be stated as follows: if two players agree to play a game in which one has to win a certain number of (...) rounds in order to win the pool, but if they break the game off before either of them has won the required number of rounds, how should the pool be distributed?Our article has two aims: it provides the readers with the first published English translation of De incerti aestimatione, and it also gives them a brief commentary that explains Leibniz’s philosophical and mathematical concepts necessary in order to understand this work. The translation is as literal as possible throughout; it shows how Leibniz struggled at times to find a solution to the division problem and how he approached it from different angles. The commentary discusses Leibniz’s views on four key concepts: fairness, hope, authority and possibility. The commentary then outlines how Leibniz attempted to solve the problem of division. (shrink)

The introduction has a brief statement, sufficient for the purpose of this paper, which describes in general terms the notion of probability logic on which the paper is based. Contributions made in the eighteenth century by Leibniz, Jacob Bernoulli and Lambert, and in the nineteenth century by Bolzano, De Morgan, Boole, Peirce and MacColl are critically examined from a contemporary point of view. Historicity is maintained by liberal quotations from the original sources accompanied by interpretive explanation. Concluding the paper is (...) a summary. (shrink)

On the surface the notions of ideas, truth, and knowledge seem to be purely epistemological notions. In this study I propose that we understand Leibniz' treatments of ideas, truth, and knowledge as ontological notions as well as epistemological notions. ;Under this proposed reading as idea in its ontological aspect is a possibility and is a real in the Leibnizian Metaphysics. Leibniz treats the epistemological aspect of an idea as a special kind of disposition which synthesizes the truths to be found (...) in understanding ideas as acts and ideas as objects. ;As an ontological notion, truth is a structural notion. Specifically, truth is the structure of those ontological entities called "ideas." Leibniz discusses truth as an epistemological notion in terms of two tests. We know a necessary truth by analysis and we know a contingent truth by experience. ;Knowledge considered from the ontological side of my distinction is the direct, immediate and non-symbolic awareness of reality as it is. Of course God's knowledge is the only example of this ideal. From the human, epistemological perspective, Leibniz treats knowledge in terms of the adequacy of symbolic representations of reality. By recognizing degrees of knowledge he avoids the unworkable demand for perfection in the foundations theory of knowledge. ;Understanding Leibnizian ideas, truth, and knowledge as both epistemological and as ontological notions has some interesting consequences. First, there is a gain in our understanding of Leibniz' metaphysics. Second, there is an improvement in the placement of Leibniz in the history of philosophy . Third, this interpretation provides an aid in sorting out what is correct and what is mistaken in the criticism and interpretation of Leibnizian philosophy in the recent literature. (shrink)

This paper seeks to reconstruct an important controversy between leibniz and malebranche over innate ideas. It is argued that this controversy is in some ways more illuminating than the better-Known debate between leibniz and locke, For malebranche's objections to innate ideas raise fundamental questions concerning the status of dispositions and the relationship between logic and psychology. The paper shows that in order to meet malebranche's objections, Leibniz adopts a strategy which is doubly reductionist: ideas are reduced to dispositions to think (...) in certain ways, And these dispositions are in turn reduced to unconscious perceptions. It is suggested that malebranche's platonist commitment to the existence of abstract entities forces leibniz to reveal the extent of his nominalism. (shrink)

I want to show that Leibnizian mode to thinking is based in a kind of logic of concepts. As an example, his first attempt to sum infinite series is analyzed. The question concerning the justification of the Leibnizian syllogism leads to the analysis of the fundamental definition. A conclusion obtained by “real-definitions” (“Realdefinitionen”) is logically justified. It is classified as a "Vernunftwahrheit". A conclusion obtained by paradoxical definitions (paradoxe Definitionen) is classified as a “Tatsachenwahrheit”. According to Leibniz it has validity (...) by contingency. A conclusion obtained by “impossible definitions” is logically unjustified. (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)

This paper discusses the problem of sensible qualities, an important, but underestimated topic in Leibniz's epistemology. In the first section, the confused character of sensible ideas is considered. Produced by the sensation alone, ideas of sensible qualities cannot be part of distinct descriptions of bodies. This is why Leibniz proposes to resolve sensible qualities by means of primary or mechanical qualities, a thesis which is analysed in the second section. Here, I discuss his conception of nominal definitions as distinct empirical (...) representations. The provisional and modifiable status of nominal definitions is then explained in the third section. Since nominal descriptions always contain sensible determinations, Leibniz claims that empirical knowledge is indefinitely changeable according to progress in sciences. In the final section, I address the criterion of coherence that enables us to approve of hypotheses that are based on both sensible and empirical properties. (shrink)

In the New Essays on Human Understanding, Leibniz argues chapter by chapter with John Locke's Essay Concerning Human Understanding, challenging his views about knowledge, personal identity, God, morality, mind and matter, nature versus nurture, logic and language, and a host of other topics. The work is a series of sharp, deep discussions by one great philosopher of the work of another. Leibniz's references to his contemporaries and his discussions of the ideas and institutions of the age make this a fascinating (...) and valuable document in the history of ideas. The work was originally written in French, and the version by Peter Remnant and Jonathan Bennett, based on the only reliable French edition (published in 1962), first appeared in 1981 and has become the standard English translation. It has been thoroughly revised for this series and provided with a new and longer introduction, a chronology on Leibniz's life and career and a guide to further reading. (shrink)

The main aim of our paper is to implement Leibniz's analysis of the conditional right in the framework of a dialogical approach to Public Announcement Logic. According to our view, on one hand: PAL furnishes a dynamic epistemic operator which models communication exchange between different agents that seems to be very close to Leibniz understanding of the dynamics between the truth of a proposition and the knowledge of the truth of that proposition (Leibniz calls the latter certification of its truth); (...) on the other hand, the dialogical approach provides a semantics for the dynamic epistemic operator in the context of conditional right by means of which: (i) the exchange between agents leading to a public announcement amounts to the (contractual) interaction of commitments of both the benefactor and the beneficiary of a conditional right (ii) the notion of certification is understood as an action, namely as a move where the beneficiary asks the benefactor to stand to his commitments, (iii) some restrictions specific to the logical nature of the head and the tail of the conditional right can be implemented by combining PAL with some features of linear logic within the same theory of meaning. (shrink)

In the Discourse on Metaphysics Leibniz writes, 'Our perceptions are always true, it is our judgments that come from ourselves that deceive us' (section 14). Leroy Loemker in his 'Leibniz's Doctrine of Ideas' criticizes this account of error. His main worry can be presented in the form of the following syllogistic argument, which he derives from Leibniz's doctrine of ideas: (a) There cannot be a false perception; (b) All judgments are perceptions; and therefore (c) There cannot be a false judgment. (...) However, in this paper I argue that Leibniz can distinguish between a perception and a judgment in their semantic aspect. The sense in which a perception turns out to be false (or true) for Leibniz is different from the sense in which a judgment turns out to be false (or true). This is because, while a perception, understood in Leibniz's terms, lacks truth-conditions, a judgment, in being representational, has such conditions. Thus while a perception remains true always, a judgment can be false. Pointing to the equivocal use of 'false' in (a) and (c) above, I conclude that (c) does not follow from (a) and (b). (shrink)

Leibniz’s De incerti aestimatione, which contains his solution to the division problem, has not received much attention, let alone much appreciation. This is surprising because it is in this work that the definition of probability in terms of equally possible cases appears for the first time. The division problem is used to establish and test probability theory; it can be stated as follows: if two players agree to play a game in which one has to win a certain number of (...) rounds in order to win the pool, but if they break the game off before either of them has won the required number of rounds, how should the pool be distributed?Our article has two aims: it provides the readers with the first published English translation of De incerti aestimatione, and it also gives them a brief commentary that explains Leibniz’s philosophical and mathematical concepts necessary in order to understand this work. The translation is as literal as possible throughout; it shows how Leibniz struggled at times to find a solution to the division problem and how he approached it from different angles. The commentary discusses Leibniz’s views on four key concepts: fairness, hope, authority and possibility. The commentary then outlines how Leibniz attempted to solve the problem of division. (shrink)

Scholars have long noted that, for Leibniz, the attributes or Ideas of God are the ultimate objects of human knowledge. In this paper, I go beyond these discussions to analyze Leibniz’s views about the nature and limitations of such knowledge. As with so many other aspects of his thought, Leibniz’s position on this issue—what I will call his divine epistemology—is both radical and conservative. It is also not what we might expect, given other tenets of his system. For Leibniz, “God (...) is the easiest and the hardest being to know.” God is the easiest to know, in that to grasp some property of an essence is to attain a knowledge of the divine essence, but God is also the most difficult to know, in that “real knowledge” of the divine essence is not available to finite beings. There is an enormous gap between the easy and the real knowledge of God, but for Leibniz, this gap is a good thing, since the very slowness of our epistemological journey prepares us morally for its end. (shrink)