Buridan's Logical Works: Summulae de dialectica https://www.historyoflogic.com/buridan-logic-one.htm History of Logic from Aristotle to Gödel by Raul Corazzon | e-mail: [email protected] Buridan's Logical Works. I. An Overview of the Summulae de dialectica INTRODUCTION: THE PLACE OF BURIDAN IN THE HISTORY OF PHILOSOPHY 1 di 22 29/12/2018, 18:37 Buridan's Logical Works: Summulae de dialectica https://www.historyoflogic.com/buridan-logic-one.htm "In this essay, I wish to question the view that the distinction between medieval and early modern philosophy is primarily one of method. I shall argue that what has come to be known as the modern method in fact owes much to the natural philosophy of John Buridan (ca. 1295-1361), a secular arts master who taught at the University of Paris some three centuries before Descartes. Surrounded by conflicts over institutional governance and curricular disputes, Buridan emerged as a forceful voice for the independence and autonomy of teachers in the faculty of arts, arguing that philosophy as properly practiced belonged to them, the "artists artistae", not to those who taught in the so-called 'higher' faculties of theology, law, and medicine. Now such voices had been heard before at Paris, most notably from Averroist arts masters in the late 13th and early 14th-centuries.(*) Buridan is different, however, because unlike Boethius of Dacia and John of Jandun, he knew how to make the case for artistic autonomy without denigrating the theology and thereby inviting official condemnation. His trick was not to argue that there are 'two truths', one acquired and the other revealed, which might well come into conflict with each other, or that propositions whose truth has been revealed in scripture in no way qualify as scientia. It was rather to recognize the profoundly different methods of theology and philosophy, without losing sight of the fact that what counts as evidence in a proof in natural philosophy does not work in a theological argument, even if both have the same conclusion, such as that the human soul is immortal. Buridan seems to think that if only people would respect the differences between the rules of philosophical and theological inquiry, no conflicts would arise. He is not so naive as to claim this could ever happen, of course. But it does explain why he almost always diagnoses such conflicts in terms of some logical or linguistic confusion on the part of the people who propose them. Buridan is also different because in him the secularizing sentiment already present in the Latin Averroists begins to take shape as a way of doing philosophy, i.e., as a philosophical grammar. This is clear in his greatest work, the Summulae de Dialectica, a comprehensive account of the titles of philosophical discourse written for the guidance of students and scholars alike. Due in large part to the enormous popularity of the Summulae and his commentaries on Aristotle's metaphysics and natural philosophy -- copies were made or (later) printed and circulated throughout France, Germany, Italy, Scotland, and Eastern Europe, well into the 16th century -- Buridan helped make possible the secularization of philosophical practice a crucial first step on the road to modernism." (pp. 34-35) Notes (*) Fabienne Pironet, "Le sujet de la science dans les "Regulae" de Descartes", Medioevo, 24, 1998, pp. 267-281. From: Jack Zupko, "John Buridan and the Origins of Secular Philosophical Culture", in: Stefano Caroti, Jean Celeyrette (eds.), Quia inter doctores est magna dissensio. Les débats de philosophie naturelle à Paris au XIV siècle, Firenze: Olschki 1994, pp. 33-48. BURIDAN'S LOGICAL WORK "The extant writings of Buridan consist of the lectures he gave on subjects comprised in the curriculum of the faculty of Arts at Paris. In the fourteenth century this curriculum was largely based on study of the treatises of Aristotle, along with the Summulae logicales of Peter of Spain and other medieval textbooks of grammar, mathematics and astronomy. Buridan composed his own textbook of logic, a Summula de dialectica, as a "modern" revision and amplification of the text of Peter of Spain, and he also wrote two treatises on advanced topics of logic, entitled Consequentiae and Sophismata, which are among the most interesting contributions to late medieval logic. All of his other works are in the form of 2 di 22 29/12/2018, 18:37 Buridan's Logical Works: Summulae de dialectica https://www.historyoflogic.com/buridan-logic-one.htm commentaries, and of critical books of Questions, on the principal treatises of the Aristotelian corpus. The literal commentaries are extant only in unpublished manuscript versions, but the books ofQuestions on Aristotle's Physics, Metaphysics, De anima, Parva naturalia, Nicomachean Ethics, and Politics were published, along with Buridan's writings in logic, after the invention of printing. (...) Most of the printed editions represent the lectures Buridan gave during the last part of his teaching career, though earlier versions are found among the unpublished manuscript materials. Until a critical study of the manuscripts is made, however, there is no sure way of determining any order of composition among Buridan's works, or of tracing the development of his thought over the thirty odd years of his academic career. Buridan made significant and original contributions to logic and physics, but one of his major achievements was that of vindicating the independence of natural philosophy as a respectable study in its own right, and of defining the objectives and methodology of the scientific enterprise in a manner which gave warrant for its autonomy in relation to dogmatic theology and metaphysics. This achievement was intimately connected with the movement of fourteenth century thought known as Nominalism, and with the controversies precipitated at the universities of Oxford and Paris by the doctrines associated with William of Ockham. Buridan's own philosophical position was thoroughly nominalistic, and indeed very similar to that of Jean de Mirecourt, a theologian of Paris whose teachings were condemned in 1347 by the chancellor of the university and the faculty of theology. That Buridan was able to escape the charges of theological scepticism that were directed against his fellow nominalists of the theological faculty was no doubt due, in part, to his personal qualities of prudence and diplomacy. But it was also due to his methodological, rather than metaphysical, way of employing the logic and the epistemological doctrines of nominalism in formulating the character and the evidential foundations of natural philosophy. The formal logic presented in Buridan's Summula de dialectica is closely related, in topical structure and in terminology, to the so-called terminist logic of the thirteenth century represented by the textbooks of William of Sherwood and Peter of Spain. Though it presupposes the nominalist thesis that general terms are signs of individuals and not of common natures existing in individuals, it does not exhibit any strong evidence of direct influence by the logical writings of Ockham, and it may well have been developed independently of such influence on the basis of the modern logic (logica moderna) already well established in the Arts faculties of Oxford and Paris. The doctrine of the supposition of terms, basic to this logic, is used in defining the functions of logical operators or syncategorematic signs in determining the truth conditions of categorical propositions of various forms, and in formulating the laws of syllogistic inference both assertoric and modal. Treatises on topical arguments, fallacies, and on the demonstrative syllogism, conclude the work. Buridan's Sophismata, designed to constitute a ninth part of theSummula, was apparently written much later in his life, since it contains criticisms of the theory of propositional meanings, or complexe significabilia, which Gregory of Rimini introduced in 1344. This work presents a very fully developed analysis of meaning and truth which corresponds fairly closely to that of Ockham's Summa logicae, but it goes well beyond the work of Ockham in presenting original and highly advanced treatments of the problem of the non-substitutivity of terms occurring in intensional contexts, and of the problem of self-referential propositions represented by the paradox of the Liar. Buridan's treatment of these problems exhibits a level of logical insight and skill not again equalled until very recent times. His treatise on Consequentiae, which develops the whole theory of inference on the basis of propositional logic, marks another high point of medieval logic whose significance has only been appreciated in the twentieth century." (pp. 442-444 of the reprint) From: Moody Ernest A. Moody, "Jean Buridan", in: Charles C. Gillispie (ed.), Dictionary of Scientific Biography, Vol. II, New York: Charles Scribner's Sons 1969, pp. 603-608. Reprinted in: E. A. Moody, Studies in Medieval Philosophy, Science, and Logic. Collected Papers 1933-1969, Berkeley: University of California Press 1975, pp. 441-453. 3 di 22 29/12/2018, 18:37 Buridan's Logical Works: Summulae de dialectica https://www.historyoflogic.com/buridan-logic-one.htm PHILOSOPHICAL GRAMMAR "Anneliese Maier once remarked of later scholastic natural philosophy that, «what changes is the method of knowing nature», so that «what is interesting is not the knowledge (scientia), but the method of knowing (modus sciendi)».(36) Buridan was one of the major agents of this change. His contribution was to rewrite the grammar of philosophy, supplanting older forms of inquiry with the more powerful method of the Summulae de Dialectica, the compendium of logical teachings that was his masterwork. By welding the logic of the moderni together with the indigenous Parisian tradition of propositional logic into a single, comprehensive package, he was able to effect a quiet revolution in the speculative sciences. The Summulae is essentially a 'how-to' book for the philosopher.