This volume is the first annotated translation in any language of the entire text of the Summulae de dialectica, by the Parisian master of arts John Buridan (1300-1358). One of the most influential works in the history of late medieval philosophy, the Summulae is Buridan's systematic exposition of his nominalist philosophy of logic. Buridan's doctrine spread rapidly and for some two hundred years was dominant at many European universities. His work is of increasing interest today not (...) only to historians of medieval philosophy but also to modern philosophers, several of whom find in Buridan's ideas important clues to problems of contemporary philosophy. Gyula Klima provides a substantial introduction to Buridan's life and work and discusses his place in the history of logic. Through extensive notes Klima assists philosopher and medievalist alike to read Buridan with understanding and insight. Those with a philosophical interest in the relations among the structures of language, thought, and reality will find much to ponder in the Summulae. (shrink)

This publication offers the first critical edition of John Buridan’s second set of questions on Aristotle's “De generatione et corruptione”. The edition was made by Michiel Streijger, Paul Bakker and Hans Thijssen. First published as a printed book in 2010, the publication has been converted to open access with the CC BY-NC-ND license as of September 2023.

John Buridan (d. ca. 1360) was one of the most talented and influential philosophers of the later Middle Ages. His Questions Commentary on the eight books of Aristotle's Physics is the most important witness to Buridan's teachings in the field of natural philosophy. This volume presents the first critical edition of books III and IV of the final redaction of Buridan's Questions Commentary on the Physics. The critical edition of the Latin text is accompanied by a (...) detailed guide to the contents of Buridan's questions by Edith D. Sylla. (shrink)

John Buridan was a fourteenth-century philosopher who enjoyed an enormous reputation for about two hundred years, was then totally neglected, and is now being 'rediscovered' through his relevance to contemporary work in philosophical logic. The final chapter of Buridan's Sophismata deals with problems about self-reference, and in particular with the semantic paradoxes. He offers his own distinctive solution to the well-known 'Liar Paradox' and introduces a number of other paradoxes that will be unfamiliar to most logicians. (...) class='Hi'>Buridan also moves on from these problems to more general questions about the nature of propositions, the criteria of their truth and falsity and the concepts of validity and knowledge. This edition of that chapter is intended to make Buridan's ideas and arguments accessible to a wider range of readers. The volume should interest many philosophers, linguists and logicians, who are increasingly finding in medieval work striking anticipations of their own concerns. (shrink)

This edition of that chapter is intended to make Buridan's ideas and arguments accessible to a wider range of readers.

'De syllogismis' is the fifth treatise of John Buridan's 'Summulae dialecticae', a textbook he wrote for his logic course in the Faculty of Arts at the University of Paris. 'De syllogismis' contains material related to Aristotle's Analytica Priora and Boethius's 'De hypotheticis syllogismis'. The textbook discusses inferences involving not only propositions de inesse, but also propositions featuring oblique, reduplicative and infinite terms. Buridan displays a keen interest in modal inferences and inferences involving propositional attitudes. Buridan's De (...) syllogismis continues along the lines of his nominalist conception of the relations between mind, language and reality. (shrink)

See collation, showing variants found in the early printed edition and some manuscripts. The corrected text following omits rejected variants and implements those that have been accepted.

This critical edition is the first edition of John Buridan's commentary on Aristotle's Topics. The work is preserved in one complete manuscript of good quality and in four abbreviated versions. Buridan composed the work at the University of Paris in the first half of the fourteenth century, and the work illustrates very well how the commentators of this period took a freer attitude to Aristotle than previously and were selective about the passages which they commented upon. In (...) book II Buridan discussed a number of sophisms which are not found in his collection of sophisms. The commentary was quite influential in the fifteenth century, particularly on the teaching in the universities of Central and Eastern Europe. (shrink)

If an argument is valid, it is impossible for its premises to be true, and its conclusion false. But how should we understand these notions of truth and impossibility? Here, I present the answers given by John Buridan (ca. 1300-60), showing (i) how he understands truth in his anti-realist metaphysics, and (ii) how he understands modality in connection with causal powers. In short: if an argument exists and is valid, there does not exist a power capable of making (...) the premises true and, at the same time, making the conclusion false. (shrink)

It may come as a surprise to readers familiar with the life and work of the Arts Master that he discusses the Eucharist at all. As he likes to remind us, theological topics are generally out of his wheelhouse. Even so, in his Questions on the “Metaphysics” of Aristotle (QM) 4.6, Buridan takes the sacrament of the Eucharist as a key data point in his discussion of Aristotle’s Categories. In the Eucharist, the accidents of the bread and wine—their color, (...) texture, and so on—remain intact, but the underlying substance is transubstantiated into the body and blood of Christ. Accordingly, God can preserve accidents independent of their underlying substance. Therefore, for our part we can use accidental terms, like whiteness, without connoting any substances, like communion bread. Moreover, it follows that, contrary to Aristotle, substance and the accidental categories are not the most general genera. Instead, being (ens) is, as Buridan concludes. Here, I trace Buridan’s thought on the metaphysical and semantic matters of substance in light of the Eucharist. The Eucharist is for him not only a theological truth, but a metaphysical and semantic datum as well. I conclude by asking why Buridan did not take any and all questions about the Eucharist to be out of his ken. What does this tell us about his attitude toward theology? This paper also includes, as an appendix, the first ever English translation of the question under discussion (QM 4.6): “Does the term being (ens) signify substances and accidents by one single concept or notion?”. (shrink)

Una de las características de la transmisión manuscrita de los _Tractatus _ _de Pedro Hispano es el hecho de que el tratado sobre las _Categorías _no siempre ocupa el mismo lugar al interior de la obra. En algunos manuscritos se encuentra en tercer lugar, después del tratado acerca de la _Isagoge _de Porfirio, siguiendo el orden tradicional de la _logica vetus. _Pero en algunos otros, se encuentra en quinto lugar, después del tratado sobre los _Tópicos _y antes del tratado sobre (...) la suposición. En los dos casos, el lugar de las _Categorías _de Aristóteles en la lógica es definido por la noción de “término”. El propósito de este artículo es entender por qué ocurre esta variación, ya que no es teóricamente neutral. Por tanto, para atender al problema del orden de aparición del tratado sobre las _Categorías _dentro de la lógica, se presentarán tres de los más destacados comentaristas de los _Tractatus_: Juan Buridan, Juan Versor y Pedro Tartaret. Este ejercicio proporcionará algunas conclusiones sobre la relación entre las categorías y la teoría de la suposición, y también sobre la _vexata quaestio _acerca del sujeto de las categorías. (shrink)

John Buridan was a fourteenth-century philosopher who enjoyed an enormous reputation for about two hundred years, was then totally neglected, and is now being 'rediscovered' through his relevance to contemporary work in philosophical logic. The final chapter of Buridan's Sophismata deals with problems about self-reference, and in particular with the semantic paradoxes. He offers his own distinctive solution to the well-known 'Liar Paradox' and introduces a number of other paradoxes that will be unfamiliar to most logicians. (...) class='Hi'>Buridan also moves on from these problems to more general questions about the nature of propositions, the criteria of their truth and falsity and the concepts of validity and knowledge. This edition of that chapter is intended to make Buridan's ideas and arguments accessible to a wider range of readers. The volume should interest many philosophers, linguists and logicians, who are increasingly finding in medieval work striking anticipations of their own concerns. (shrink)

What is an occurrent mental state? According to a common scholastic answer such a state is at least in part a quality of the mind. When I newly think about a machiatto, say, my mind acquires a new quality. However, according to a view discussed by John Buridan (who rejects it) and John of Mirecourt (who is condemned in 1347 for considering it “plausible”), an occurrent mental state is not even in part a quality. After sketching some (...) of the history of this position, I will present two common arguments against it—the argument from change and the argument from agency. I will then turn to Mirecourt’s own position on the matter. Mirecourt, I show, in fact offers us two different theories about occurrent mental states. The first, which I call the conservation theory, accepts that mental states are in part qualities. However, a mental state is a quality together with an action on the side of the mind, namely, its conservation of a quality within itself. The second position, which I will call the pure-action theory, holds that an occurrent mental state is not even in part a quality; instead, it is an action the mind performs which is neither the production nor the conservation of a quality within itself. Mirecourt characterizes such pure actions as “modes” of the mind, and it is this position which is condemned in 1347. In the final section, I turn to an objection that both Buridan and Mirecourt raise against the pure-action theory: if accidental states of the mind are mere modes of the mind, then why not suppose that all accidents are mere modes of the subjects which they qualify? (shrink)

How induction was understood took a substantial turn during the Renaissance. At the beginning, induction was understood as it had been throughout the medieval period, as a kind of propositional inference that is stronger the more it approximates deduction. During the Renaissance, an older understanding, one prevalent in antiquity, was rediscovered and adopted. By this understanding, induction identifies defining characteristics using a process of comparing and contrasting. Important participants in the change were Jean Buridan, humanists such as Lorenzo Valla (...) and Rudolph Agricola, Paduan Aristotelians such as Agostino Nifo, Jacopo Zabarella, and members of the medical faculty, writers on philosophy of mind such as the Englishman John Case, writers of reasoning handbooks, and Francis Bacon. (shrink)

This paper examines Aristotle’s account of the individuation of causal powers, which dominated much of scholastic thought about powers, and argues that John Buridan rejected it. It contends that Buridan criticizes Aristotle’s account on two counts. First, he attacks Aristotle’s view that we ought to individuate powers by appeal to their respective activities. Second, Buridan objects to Aristotle’s “single-track” account, which correlates one type of power with only one type of activity. Against this, it is argued, (...) Buridan adopts a multi-track approach, according to which a single power type may be correlated with many different types of activities. The paper claims that the basic idea of Buridan’s multi-track view is still defensible today, and can be viewed as a viable alternative to the contemporary single-track account of power individuation defended, for instance, by Jonathan Lowe. (shrink)

John Buridan’s theory of persistence is based on a metaphysical foundation that has been misrepresented by contemporary scholars. I argue that this fact is both (i) suggested by his treatment of persistence itself, and (ii) explicit in his clearest exposition of the foundations of persistence. I also argue that while this fact has historical interest, its primary interest is philosophical in nature: it shows Buridan developing a distinction that contemporary philosophers find useful in elaborating a metaphysical basis (...) for theories of persistence. (shrink)

John Buridan was the most famous philosophy teacher of his time, and probably the most influential. In this important new book, Jack Zupko offers the first systematic exposition of Buridan's thought to appear in any language. Zupko uses Buridan's own conception of the order and practice of philosophy to depict the most salient features of his thought, beginning with his views on the nature of language and logic and then illustrating their application to a series of (...) topics in metaphysics, natural philosophy, and ethics. Part 1 of John Buridan considers the picture of language and logic developed in Buridan's Summulae de dialectica. Buridan systematically overhauled the logic he first learned and later taught at the University of Paris, redeeming the older tradition of Aristotelian logic in terms, propositions, and arguments. This made possible newer and more powerful forms of philosophical discourse. The second part of this volume provides a reading of Buridan's philosophy, showing how this discourse shaped his treatment of speculative questions such as the relation between soul and body, the nature of knowledge, the proper subject of psychology, the function of the. (shrink)

This article considers the relationship between John Buridan’s natural philosophy and medicine. By examining some aspects of Buridan’s description of the human body related to sensation, nutrition, and generation—especially as they were framed in the so-called “controversy between philosophers and physicians”—this article shows that, though mostly faithful to Aristotelian doctrine, Buridan’s theoretical biology relies to a large extent on medical ideas.

Is a human being something that is one per se, or are humans composed of two independent substances? Treating the soul as the form of an organic body seems to offer one way of addressing the difficulty. But the debates about the nature of the soul which began to emerge in the 1270s made this question problematic. This article considers Buridan’s solution to the problem of how to unify what is corporeal and divisible on the one hand with what (...) is incorporeal and indivisible on the other. Beginning with sensation, which concerns the unity of the sensitive soul and sense data, we turn to the act of thinking, where the intellective soul is united with the image or phantasm qua mover, leading to the realization that the unity of a human being is no longer self-evident. To solve the problem, Buridan takes up and transforms ways of thinking about the human soul inherited from older debates around Averroist psychology, such as the theory of two subjects and the conjunction of the sensible with the intelligible during cognitive activity. (shrink)

. According to John Buridan, the time for which a statement is true is underdetermined by the grammatical form of the sentence – the intention of the speaker is required. As a consequence, truth-bearers are not sentence types, nor sentence tokens plus facts of the context of utterance, but statements. Statements are also the bearers of logical relations, since the latter can only be established among entities having determined truth-conditions. This role of the intention of the speaker in (...) the determination of what is said by an utterance is not isolated in medieval semantics. (shrink)

Aquinas, Ockham, and Burdan all claim that a person can be numerically identical over time, despite changes in size, shape, and color. How can we reconcile this with the Indiscernibility of Identicals, the principle that numerical identity implies indiscernibility across time? Almost all contemporary metaphysicians regard the Indiscernibility of Identicals as axiomatic. But I will argue that Aquinas, Ockham, and Burdan would reject it, perhaps in favor of a principle restricted to indiscernibility at a time.

In this paper we look at the suitability of modern interval-based temporal logic for modeling John Buridan’s treatment of tensed sentences in his Sophismata. Building on the paper, we develop Buridan’s analysis of temporal logic, paying particular attention to his notions of negation and the absolute/relative nature of the future and the past.We introduce a number of standard modern propositional interval temporal logics to illustrate where Buridan’s interval-based temporal analysis differs from the standard modern approaches. We (...) give formal proofs of some claims in, and sketch how the standard modern systems could be defined in terms of Buridan’s proposals, showing that his logic can be taken as more basic. In diesem Aufsatz betrachten wir das Geeignetsein einer modernen intervallbasierten temporalen Logik für die Modellierung von John Buridans Behandlung zeitabhängiger Sätze in seinen Sophismata. Aufbauend auf den Aufsatz stellen wir Buridans Analyse der temporalen Logik dar, mit besonderer Berücksichtigung seiner Begriffe der Negation und der absoluten/relativen Natur der Zukunft und der Vergangenheit. Wir führen einige standardmäßige moderne intervallbasierte temporale Aussagenlogiken ein, um zu illustrieren, wo Buridans intervallbasierte temporale Analyse von den standardmäßigen modernen Zugangsweisen abweicht. Wir geben formale Beweise einiger Behauptungen in an und skizzieren, wie die standardmäßigen modernen Systeme im Sinne der Vorschläge Buridans definiert werden könnten; wir zeigen damit, dass seine Logik als die grundlegendere aufgefasst werden kann. (shrink)

The solution John Buridan offers for the Paradox of the Liar has not been correctly placed within the framework of his philosophy of language. More precisely, there are two important points of the Buridanian philosophy of language that are crucial to the correct understanding of his solution to the Liar paradox that are either misrepresented or ignored in some important accounts of his theory. The first point is that the Aristotelian formula, ` propositio est vera quia qualitercumque significat (...) in rebus significatis ita est ', once amended, is a correct way to talk about the truth of a sentence. The second one is that he has a double indexing theory of truth: a sentence is true in a time about a time, and such times should be distinguished in the account of the truth-conditions of sentences. These two claims are connected in an important way: the Aristotelian formula indicates the time about which a sentence is true. Some interpreters of the Buridanian solution to the paradox, following the lead of Herzberger, have missed these points and have been led to postulate truth-values gaps, or surrogates of truth-value gaps, when there is nothing of this sort in his theory. I argue against this tradition of interpretation of Buridan and propose an interpretation of his solution to the Liar. (shrink)

In this paper we will argue that the ontology implicit in John Buridan’s modal octagon commits him to a form of contingentism. In particular, we will argue that Buridan is committed to denying the validity of the Barcan and converse Barcan formulae.

This article revisits the manuscript tradition and the different redactions of John Buridan’s commentaries on Aristotle’s Physics. The aim of the article is threefold. First, it makes some corrections to the lists of manuscripts containing the third redaction and the final redaction of Buridan’s questions commentary on the Physics. Second, it argues that manuscript Zaragoza, Biblioteca Capitular de la Seo, cod. 15-61, ff. 1r-62v, contains a previously unknown version of the final redaction (together with the standard version (...) from f. 62v onwards). Third, to facilitate further study of the manuscripts of Buridan’s questions on the Physics and their mutual relations, appendices at the end of the article provide detailed tables of contents for the third redaction and the final redaction, as well as editions of selected questions from the Zaragoza manuscript, the third redaction of Buridan’s questions on the Physics, and the so-called Quaestiones breves. (shrink)

This article provides the first edition of a series of eight Quaestiones de secretis mulierum by John Buridan. The introduction discusses the manuscript tradition and the relationship between Buridan’s quaestiones and pseudo-Albertus Magnus’ treatise De secretis mulierum, concluding that Buridan’s questions constitute a genuine commentary on pseudo-Albert’s text. Specifically, the eight questions by Buridan seem to be an extensive elaboration on the preface and on the first chapter of pseudo-Albert’s text.

Buridan's life, works, and influence -- Buridan's logic and the medieval logical tradition -- The primacy of mental language -- The various kinds of concepts and the idea of a mental language -- Natural language and the idea of a formal syntax in Buridan -- Existential import and the square of opposition -- Ontological commitment -- The properties of terms (proprietates terminorum) -- The semantics of propositions -- Logical validity in a token-based, semantically closed logic -- The (...) possibility of scientific knowledge -- Buridan's anti-skepticism -- Buridan's essentialist nominalism. (shrink)

This chapter contains sections titled: Logic Metaphysics and physics Ethics.

The study of the medieval reception of Aristotle’s Topics has largely been oriented toward debates on dialectical argumentation. And this is surely right. Nonetheless, I wish to approach John Buridan’s commentary on the Topics from another perspective, which highlights some semantic features of the set of predicates around which the work is organized. Thus, in my paper I will first reconstruct Buridan’s account of the identification of the predicates discussed in the Topics. I will argue that, for (...) him, they are different in that they reflect one or more features of the way in which definiens and definiendum relate. By doing this, I will shed light on the role the notion of definition plays in Buridan’s commentary, so that an interpretation of it as a work on definition becomes promising. In the second part of the paper, I will offer an analysis of Buridan’s first move in his commentary toward a theory of definition. It concerns the problem of whether there is a definition of definition. In examining Buridan’s answer, I will argue for the close connection between his treatment of definitions and his theory of supposition, so that distinctions among the different modes of supposition help him to disambiguate statements in their possible meanings, and thus to clarify the difficulty related to the definability of definition. (shrink)

Proclaiming Louis Pasteur as the “Founder of Stereochemistry”, the distinguished Scottish chemist, Crum Brown, addressing a late nineteenth-century audience of Edinburgh savants, drew attention—as Pasteur had incessantly done—to the intimate relationship between living organisms and the optical activity of compounds sustaining them. It seemed to Crum Brown “that we must go very much further down in the scale of animate existence than Buridan's ass, before we come to a being incapable of giving practical expression to a distinct preference for (...) one of two objects differing only in being one to the right and the other to the left”. Crum Brown's lecture must have been entertaining, but it was also motivated by a serious desire to do justice to a particular assertion of Pasteur—an assertion which had, moreover, been misunderstood and dismissed by no less a chemical genius than Wilhelm Ostwald. Writing at a time when the majority of his colleagues were stressing the resemblances between inorganic and organic compounds, Pasteur had insisted that he “could not point out the existence of any more profound distinction between the products formed under the influence of life and all others” than that “artificial products have … no molecular asymmetry”. Pasteur was obliged to concede that the chemist might produce enantiomorphic pairs of isomers, but without resorting to a manual separation of crystals he was powerless to imitate Nature's performance, powerless to fabricate by chemical means a separate optical isomer, divorced from its partner. Now it was not only Crum Brown who felt that chemists had brushed aside this proposition of Pasteur. In his 1898 Presidential Address to the chemical section of the British Association, Professor F. R. Japp also complained that the possible vitalistic implications of Pasteur's distinction between natural and artificial products had been misapprehended or tacitly ignored. (shrink)

This is a brief, accessible introduction to the thought of the philosopher John Buridan (ca. 1295-1361). Little is known about Buridan's life, most of which was spent studying and then teaching at the University of Paris. Buridan's works are mostly by-products of his teaching. They consist mainly of commentaries on Aristotle, covering the whole extent of Aristotelian philosophy, ranging from logic to metaphysics, to natural science, to ethics and politics. Gyula Klima argues that many of (...) class='Hi'>Buridan's academic concerns are strikingly similar to those of modern philosophy and his work sometimes quite directly addresses modern philosophical questions. (shrink)

It may come as a surprise to readers familiar with the life and work of the Arts Master that he discusses the Eucharist at all. As he likes to remind us, theological topics are generally out of his wheelhouse. Even so, in his Questions on the “Metaphysics” of Aristotle (QM) 4.6, Buridan takes the sacrament of the Eucharist as a key data point in his discussion of Aristotle’s categories. In the Eucharist, the accidents of the bread and wine—their color, (...) texture, and so on—remain intact, but the underlying substance is transubstantiated into the body and blood of Christ. Accordingly, God can preserve accidents independent of their underlying substance. Therefore, for our part we can use abstract accidental terms, like whiteness, without connoting any substances, like communion bread. Moreover, it follows that, contrary to Aristotle, substance and the accidental categories are not the most general genera. Instead, being (ens) is, as Buridan concludes. Here, I trace Buridan’s thought on the metaphysical and semantic matters of substance in light of the Eucharist. The Eucharist is for him not only a theological truth, but a metaphysical and semantic datum as well. I conclude by asking why Buridan did not take any and all questions about the Eucharist to be out of his ken. What does this tell us about his attitude toward theology?This paper also includes, as an appendix, the first ever English translation of the question under discussion (QM 4.6): “Does the term being [ens] signify substances and accidents by one single concept or notion?”. (shrink)

This book provides the Latin text and its annotated English translation of the question-commentary of John Buridan (ca. 1300-1360) on Aristotle’s “On the Soul”. Buridan was the most influential Parisian nominalist philosopher of his time. His work speaks across centuries to our modern concerns in the philosophy of mind. This volume completes the project of a volume published earlier in the same series: “Questions on the Soul by John Buridan and Others”. An appealing book for (...) scholars of Aristotle and those who are in the field of Medieval philosophy. (shrink)

The paper deals with Buridan’s approach to the problems of propositional semantics, contained in his logical works. This question can be conceived both as semantic (definition of truth) and ontological (ontological status of states of affairs). Buridan’s solution of both of these questions is based upon a terminist theory of meaning. Theory of truth is constructed as suppositional, not as significational, which enables the definition of truth in terms of the semantic values of components of a particular kind (...) of proposition. The other important problem, the semantic analysis of accusative and infinitive constructions (i.e. of sentential nominalizations), is solved within the semantics of terms by exhibiting the logical structure of a proposition. Buridan’s crucial strategy is therefore the elimination of the apparent ontological commitments of a particular discourse in terms of dismissing the denotative theory of meaning. (shrink)

The catalogues of works by John Buridan include a commentary on the De secretis mulierum by pseudo-Albertus Magnus. The same commentary is also attributed to Buridan in more general studies on medieval natural philosophy as well as in catalogues of manuscripts and repertories of incipits of medieval scientific writings. In most cases, a unique manuscript copy of this commentary is mentioned, namely Erfurt, Universitätsbibliothek, Dep. Erf., CA Q.299. However, in her Répertoire of Masters of Arts at the (...) University of Paris, Olga Weijers claims that Buridan’s commentary on De secretis mulierum can also be found in a different redaction in another manuscript: Paris, Bibliothèque Nationale de France, Ms. lat. 8513. This article examines the question of the attribution of these texts to Buridan. First, it argues that the Parisian text is not a commentary by Buridan on De secretis mulierum but rather a different version of pseudo-Albertus’ work, and second, that Buridan can be considered the author of the quest... (shrink)

This paper studies John Buridan's octagons of opposition for the de re modal propositions and the propositions of unusual construction. Both Buridan himself and the secondary literature have emphasized the strong similarities between these two octagons (as well as a third one, for propositions with oblique terms). In this paper, I argue that the interconnection between both octagons is more subtle than has previously been thought: if we move beyond the Aristotelian relations, and also take Boolean considerations (...) into account, then the strong analogy between Buridan's octagons starts to break down. These differences in Boolean structure can already be discerned within the octagons themselves; on a more abstract level, they lead to these two octagons having different degrees of Boolean complexity (i.e. Boolean closures of different sizes). These results are obtained by means of bitstring analysis, which is one of the key tools from contemporary logical geometry. Finally, I argue that this historical investigation is directly relevant for the theoretical framework of logical geometry, and discuss how it helps us to address certain open questions in this framework. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Journal of the History of Philosophy 42.2 (2004) 219-220 [Access article in PDF] Jack Zupko. John Buridan: Portrait of a Fourteenth-Century Arts Master. Notre Dame: University of Notre Dame Press, 2003. Pp. xix + 446. Cloth, $70.00. Paper, $40.00. What does the name "John Buridan" call to mind? For many, including medievalists, not much at all—at best, perhaps, a set of apparently unrelated ideas: nominalism; (...) an impetus theory of projectile motion; and a peculiar account of the will (although "Buridan's ass," the indecisive donkey caught between two equally appetizing bales of hay, is not found in Buridan's writing). In correcting this ignorance—an injustice to arguably the most famous and influential philosopher of the early-to-mid-fourteenth century—the temptation might have been to articulate Buridan's "positions" on "the big questions," allowing readers to fit Buridan into received categories. Thankfully, the present work, the first book-length study of Buridan in any language, resists this temptation. The John Buridan that emerges from Jack Zupko's skillful "exercise in philosophical portraiture" doesn't serve to simply fill gaps in our awareness of the historical record, but to enlighten and challenge our understanding of the practice of philosophy and the study of its history.Zupko emphasizes throughout that Buridan was a teacher, a master of arts in Paris. Buridan's pedagogical concerns help make sense of his central work in logic. As the basis for his arts lectures, Buridan chose Peter of Spain's Summulae Logicales, but in commenting on Peter, Buridan moves beyond creative exegisis to comprehensive renovation. Buridan (c. 1300-c. 1361) naturally wanted to accommodate terminist or via moderna supposition theory; but more importantly, he wanted a logic text that would set out a general plan of philosophical inquiry, "a compendium of methods, a 'how-to' book for the philosopher" (135). Buridan thus designed his own Summulae de Dialectica as a new authoritative logic text, and Zupko persuasively argues that its "nominalism" should be understood as less a set of doctrines in theoretical logic, than a program of logical practice, an education in logic as the ars artium, the universal intellectual tool.Zupko's portrait of "Buridan's vision of the philosophical enterprise" is thus appropriately divided into two parts. The first summarizes Buridan's method as described in the individual treatises of his Summulae. The second displays the method in practice, rehearsing and evaluating some of Buridan's arguments on various subjects. Many scholars will gravitate first to the latter part, where Zupko offers important interpretations and clarifications of Buridan's views. In these chapters, Zupko helps us to appreciate, among other things: how the problem of universals served to help Buridan define the scope of philosophy (ch. 10); the philosophical modesty of Buridan's account of the intellectual soul's presence in the body (ch. 11); the relationship between Buridan's epistemology and the skepticism of his Parisian contemporary Nicholas of Autrecourt (ch. 12); the sense in which Buridan is an "empiricist," viz an epistemic naturalist and reliabilist (ch. 13); how Buridan regarded moral psychology as applied physics, treating virtue as a kind of impetus (ch. 14); how Buridan's account of freedom can be regarded as a "perfection" of Thomistic intellectualism (ch. 15).Throughout these discussions, Zupko always keeps in sight his larger purpose of illustrating Buridan's conception of philosophical inquiry. Zupko makes much of the fact that [End Page 219] Buridan never wrote as a theologian, remaining his entire career in the arts faculty, where he wanted logic to organize secular inquiry. As Zupko notes, in this way Buridan's scholastic project seems to prefigure the "modern." But Buridan seems modern in another way as well. As Zupko points out in his "Introduction," though a cleric, Buridan never joined a religious order, so that his ideas developed independently of the Franciscan and Dominican traditions. He was, then, a teacher without a tradition—at least without deliberate allegiance to tradition, although he was in many ways the product of traditional scholastic intellectual discipline.Perhaps this... (shrink)

One of the manuscripts of Buridan’s Summulae contains three figures, each in the form of an octagon. At each node of each octagon there are nine propositions. Buridan uses the figures to illustrate his doctrine of the syllogism, revising Aristotle's theory of the modal syllogism and adding theories of syllogisms with propositions containing oblique terms (such as ‘man’s donkey’) and with ‘propositions of non-normal construction’ (where the predicate precedes the copula). O-propositions of non-normal construction (i.e., ‘Some S (some) (...) P is not’) allow Buridan to extend and systematize the theory of the assertoric (i.e., non-modal) syllogism. Buridan points to a revealing analogy between the three octagons. To understand their importance we need to rehearse the medieval theories of signification, supposition, truth and consequence. (shrink)

Jean Buridan has offered a solution to the Liar Paradox, i.e. to the problem of assigning a truth-value to the sentence ‘What I am saying is false’. It has been argued that either this solution is ad hoc since it would only apply to self-referencing sentences [Read, S. 2002. ‘The Liar Paradox from John Buridan back to Thomas Bradwardine’, Vivarium, 40 , 189–218] or else it weakens his theory of truth, making his ‘a logic without truth’ [Klima, (...) G. 2008. ‘Logic without truth: Buridan on the Liar’, in S. Rahman, T. Tulenheimo and E. Genot, Unity, Truth and the Liar: The Modern Relevance of Medieval Solutions to the Liar Paradox, Berlin: Springer, 87–112 ; Dutilh Novaes, C. 2011. ‘Lessons on truth from mediaeval solutions to the Liar Paradox’, The Philosophical Quarterly, 61 , 58–78]. Against , I will argue that Buridan's solution by means of truth by supposition does not involve new principles. Self-referential sentences force us to handle supposition more carefully, which does not warrant the accusation of adhoccery. I will also argue, against (2), that it is exaggerated to assert that this solution leads to a ‘weakened’ theory of truth, since it is consistent with other passages of the Sophismata, which only gives necessary conditions for the truth of affirmative propositions, but sufficient conditions for falsity. (shrink)

John Buridan uses the concepts of actus and habitus in his psychology to explain the difference between actual or occurrent thoughts and the dispositions to think those same thoughts. But since mental qualities are immaterial, Buridan must finesse his account of material qualities to save the psychological phenomena. He argues that thoughts and dispositions are really distinct from the human soul and from each other, and that because a thought and its corresponding disposition are different kinds of (...) quality, we cannot say that they differ merely in terms of intensity. This leaves him with the unresolved problem of explaining how one kind of psychological quality can be caused by another that is qualitatively distinct from it. (shrink)

In this paper we look at the suitability of modern interval-based temporal logic for modeling John Buridan’s treatment of tensed sentences in his Sophismata. Building on the paper [Øhrstrøm 1984], we develop Buridan’s analysis of temporal logic, paying particular attention to his notions of negation and the absolute/relative nature of the future and the past. We introduce a number of standard modern propositional interval temporal logics to illustrate where Buridan’s interval-based temporal analysis differs from the standard (...) modern approaches. We give formal proofs of some claims in [Øhrstrøm 1984], and sketch how the standard modern systems could be defined in terms of Buridan’s proposals, showing that his logic can be taken as more basic. (shrink)