Logica modernorum. A critical note on Habermas’s portrait of medieval philosophy In his monumental history of philosophy, the eminent scholar Jürgen Habermas has managed to provide us with a thorough and very nuanced overview of thousands of years of western thought. The famous philosopher paints an impressive picture of the vicissitudes of the modernisation processes featuring in the history of western philosophy. The Leitmotiv of Habermas’s narrative is the way in which throughout history philosophy dealt with the question (...) concerning the relationship between faith and reason. When it comes to the Middle Ages, it is not surprising that Habermas should focus on the opposition between Thomas Aquinas and William of Ockham. However, by confining himself to the concepts of fides and ratio, he completely overlooks thirteenth-century developments in the domain of logic. To take note of these developments is fundamental to understand the process of modernisation in philosophy. The aim of this paper is to fill in the gap, by concentrating on thirteenth-century discussions of necessity and (logical) consequences. (shrink)

v. 1. On the twelfth century theories of fallacy.--v. 2. The origin and early development of the theory of supposition.

This anonymous source publication of a university discussion held in Prague about 1400 provides us with new information about medieval semantics after Peter of Spain and Richard Billingham. The edition is the basis of a partial reconstruction of Thomas of Cleves’ _Logica_.

In the first section, our anonymous author discusses sophistria as an art. Like other authors who wrote sophistria, the author first shows that sophistria is a demonstrative science, not indeed in the sense that one is taught how to make sophistical arguments, but a science in the sense that knowledge about sophistical arguments is taught through demonstrations. In the subsequent questions on this topic, he makes a number of distinctions, for example, between a new and an old division of sophistrie, (...) between sophistria utens and docens, and between scientia realis and scientia rationis, ultimately identifying the science in question as a scientia rationis. He ends this section by identifying the ways in which the four causes pertain to this science. Unfortunately, a number of lines are missing in these questions, making it impossible to identify some of the author’s arguments which lead him to some of his positions. For example, in question 5, which asks whether the division of sophistrie into an older part and a newer part is suitable, only two arguments to the opposite are given; in question 6, which asks about the distinction between utens and docens, nothing but the question has survived, while in question 7, which asks whether the new logic of sophistria is distinct from the other parts, only one opposing argument is given. (shrink)

In this work, the papers are presented which, on the basis of L.M. de Rijk's monumental 'Logica modernorum' (1962-1967), sketch the development of medieval theories on meaning and reference from the beginnings well into the 17th century. The book also presents studies of these theories from a modern point of view.

In 1981 I published an article called Early Supposition Theory. Then as now, the magisterial work on the subject was L.M. de Rijk’s Logica Modernorum and then as now any discussion of the topic would have to rely to a great extent on the texts published there. This means that many of the problems that existed then still remain, but a couple of important new studies and several new texts have been published in the meantime, so it may (...) be time to try to take stock of the situation. I will first look at the origin of the term suppositio and then at the chronology of our source texts. (shrink)

This paper is the written version of my contribution to the International Conference «30 years Logica modernorum» held in Amsterdam in November 1997 in honor of the late prof. Lambertus M. de Rijk. Research on Oresme’s modi rerum theory was in the first stage, while now we can read the critical edition of Oresme’s Physics commentary, where modi are introduced and widely used. In this paper I shall consider Oresme’s polemical use of modi rerum, trying to set it (...) in the larger context of both his ontology and his epistemology. Oresme’s challenge to either a realist or terminist ontology by means of modi rerum conceals probably an attack to William of Ockham; Oresme refers explicitly to Ockham concerning exclusive propositions, but I think that on many other occasions the polemical target of Oresme’s criticism can be reasonably identified in William of Ockham or in some unnamed followers of the Venerabilis Inceptor. Some hints are reserved also to the possible sources of Oresme’s modi rerum. (shrink)

La teoria delle obbligazioni rappresenta un significativo esempio di come un insieme di tecniche logiche possa essere applicato, in maniera feconda, a contesti disputazionali in cui la dimensione dialogica e l’interazione tra soggetti coinvolti in un confronto dialettico hanno un ruolo di primo piano.L’attenzione che numerosi studiosi hanno manifestato nei confronti di questa parte della logica modernorum negli ultimi quarat’anni testimonia la profondità e la difficoltà dei problemi teorici che stanno alla base della teoria.Molte interpretazioni sono state avanzate (...) circa le motivazioni che spingono i logici medievali a scrivere trattati in cui il portato delle loro dottrine logiche – come, ad esempio, la teoria delle consequentiae - viene declinato ed elaboratamente applicato al gioco dialettico tra due disputanti. La gamma di tali letture comprende differenti ipotesi: la teoria delle obbligazioni potrebbe fornire un nucleo di regole per l’impostazione di un metodo assiomatico rudimentale così come rappresentare un tentativo di elaborare esercizi volti a valutare le capacità logiche degli studenti o, ancora, un gioco teorico, svincolato dall’effettiva applicazione a contesti concreti, la cui finalità sarebbe il mantenimento della coerenza logica.E’ stata sostenuta da più interpreti la funzione pedagogica svolta dalla teoria, al di là del fatto che si tratti o meno di un metodo per la conduzione effettiva di dispute reali. Un’altra linea interpretativa collega la teoria delle obbligazioni al contesto della letteratura dei sophismata e degli insolubilia, dal cui repertorio, in effetti, sono spesso tratti molti degli esempi che si incontrano nella lettura dei trattati de obligationibus. In questo senso, la teoria offrirebbe regole e schemi di risposta che un interlocutore deve utilizzare per risolvere o rispondere a enunciati problematici o paradossali. Non si può escludere, inoltre, che nella teoria si realizzi un intreccio delle differenti motivazioni sopra esposte: potrebbe trattarsi di uno strumento che viene sviluppato tanto per la risoluzione di sophismata e insolubilia quanto per indagare il rapporto tra linguaggio e metalinguaggio o altre questioni teoriche. Altri studiosi hanno infine sostenuto che lo scopo della teoria delle obbligazioni consisterebbe nell’elaborazione di un metodo adatto alla costruzione e alla discussione di esperimenti mentali e che questo costituirebbe una sorta di metametodologia della scienza medievale sulla linea del ragionamento secundum imaginationem. (shrink)

In an article published in 2003, Klaus Jacobi—using texts partially edited in De Rijk's _Logica Modernorum_—demonstrated that twelfth-century logic contains a tradition of reflecting about some of the transcendental names. In addition to reinforcing Jacobi's thesis with other texts, this contribution aims to demonstrate two points: 1) That twelfth-century logical reflection about transcendental terms has its origin in the _logica vetus_, and especially in a passage from Porphyry _Isagoge_ and in Boethius's commentary on it. In spite of the loss of (...) the major part of the Aristotelian corpus, the twelfth-century masters in logic still received some Aristotelian theses concerning the notions of one and being via Porphyry and Boethius; on the basis of such theses, they were able to elaborate a sort of proto-theory of the transcendentals as trans-categorical terms. 2) That this theory is centred on the idea that there exists a particular group of names which have the property that they can be said of everything; this group includes "being", "one", "thing" and "something". Twelfth-century masters in logic try to question the thesis that these terms are equivocal, although they do not deny it completely. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Abaelards Logik by Wolfgang LenzenSten EbbesenWolfgang Lenzen. Abaelards Logik. Paderborn: Brill | mentis, 2021. Pp. 206. Hardback, €59.00.According to its author, this book aims at reconstructing key parts of Abelard's logic while denying him a role as a hero of connexive logic or more generally as one of history's greatest logicians. At the end of the preface, we are told that "Abaelard hat die Logik seiner Zeit nicht (...) revolutioniert; er hat keine Kalküle konstruiert; und er hat auch nicht die Logik seiner Zeit auf ein höheres Niveau gehoben" (xiv).The book is divided into twenty-three chapters with titles such as "'Destruierende' versus 'separierende' Negation," "Vollkommene und unvollkommne Folgerungen," and "'Leere' Begriffe." As the titles show, it ranges over a large field. The results of Lenzen's analyses of Abelard's argumentation are presented in modern logical notation. There are many fine analyses, and despite Lenzen's refusal to see Abelard as a genius, he, too, seems to have been quite impressed by the old logician. However, at the end of the day, I am not sure that I have become any wiser about Abelard's contribution to the history of logic.Lenzen is a newcomer to the study of twelfth-century logic, and the book is marked by this in several ways. Thus, he informs the reader that "Spätestens seit Prantls Publikation der 'Geschichte der Logik im Abendlande' steht fest, dass Abaelards Traktat 'De Sillogismis Ypoteticis' sich stark an das Werk 'De syllogismo hypothetico' von Boethius (470–524) anlehnt" (165). This is quite true, but anything else would have been very remarkable, so the reference to Prantl serves no purpose.Unsurprisingly, the main source texts used are Abelard's Dialectica and his Glosae super Peri hermeneias, a part of the series of commentaries on the Ars vetus that go under the common name of Logica ingredientibus. Lenzen displays a cavalier attitude to philology. He quotes the Dialectica from De Rijk's second edition (1970), but in the bibliography he mentions that there are two editions without stating explicitly which one he quotes. In the case of the Glosae, he uses the obsolete editio princeps by Bernhard Geyer from 1927, and he does not even mention its replacement, Klaus Jacobi and Christian Strub's much superior 2010 edition in the series Corpus Christianorum, Continuatio Mediaevalis. This is inexplicable, for in his preface Lenzen describes his book as the child of a research project he began several years after the publication of the new edition. Now, fortunately, the use of Geyer does not have disastrous consequences for Lenzen's interpretation of Abelard, but had he used Jacobi and Strub's edition, he would not have had to propose a textual emendation in one place (88n17), nor would he have needed to quote, in another place, a Latin text (which he does not translate) with a nonsensical significantem instead of figurative (94n1o).Lenzen sometimes proposes textual emendations, but not always in a perspicuous way, and they are not all felicitous. For example, a quotation of L. M. de Rijk's edition of Introductiones Montane Minores in Logica Modernorum (LM) II.2 (1967) contains the phrase aliquod opposit[or]um (127n2). An unsuspecting reader would think this means De Rijk had conjecturally emended oppositorum into oppositum, for this is what opposit[or]um would mean in LM II.2. In fact, De Rijk just prints oppositum, so Lenzen's opposit[or]um must mean that he wants to correct De Rijk's text by inserting 'or,' but he forgets to tell us that he does not [End Page 520] faithfully reproduce the text quoted and that his square brackets mean something different from what they do in De Rijk's edition. This issue aside, his conjecture is superfluous, as proven by a parallel passage in LM II.2: 118. Similarly, he quotes Abelard as saying "alterum istorum [est]: vel nox vel dies" (152). The "[est]" is Lenzen's own, again superfluous, contribution to the text. By contrast, elsewhere he proposes to insert a non at LM II.2: 64.2. This time, he explains what he is doing, and I think his conjecture... (shrink)

_ Source: _Volume 53, Issue 2-4, pp 269 - 293 This article presents some results of the study of seventeen medieval treatises containing a logical analysis of the syncategorem ‘_an_’. On the one hand, a new classification is proposed of the literary genres of the _Logica Modernorum_, based on the four elements involved in the logical analysis of syncategorematic terms: the meaning of the syncategorem, logical rules, related sophisms, and proposed solutions. On the other, three texts are studied in detail, (...) showing the origins and development of the logical analysis of the syncategorem ‘_an_’ between the 12th and the 13th centuries. Finally, a comparative study is offered of different analyses of the sophism ‘_Tu scis an de mentiente sit falsum Sortem esse illum_’, a sophism that does not raise any problem as to the particle ‘_an_’, but introduces the issue of the truth conditions of the _dicta_. (shrink)

In 1980 L. M. de Rijk edited some texts connected with medieval disputation ( Die mittelaterlichen Traktate De modo opponendi et respondendi ), towards which he showed a strikingly contemptuous attitude. The reason for his contempt was that the treatises did not fit the obligationes and sophismata tradition. In this article I focus on the original version, the Thesaurus Philosophorum , to highlight the distinction of this family of treatises with respect to the “modern“ tradition. First, I study the features (...) of the disputation that can be recognised through the collection of fallacious arguments contained in the Thesaurus . Second, I briefly examine the contents of the treatise and their arrangement, showing that they are closely related to the kind of disputation in question. I hope to support the idea that neither the technique of disputation nor the contents and their arrangement deserve a straightforward rejection. (shrink)

1. Da Leibniz a Kant.--2. L'algebra della logica.

The thirteenth-century logician Lambert of Auxerre was well known for his Summa Lamberti, or simply Logica, written in the mid-1250s, which became an authoritative textbook on logic in the Western tradition. Our knowledge of medieval logic comes in great part from Lambert's Logica and three other texts: William of Sherwood's Introductiones in logicam, Peter of Spain's Tractatus, and Roger Bacon's Summulae dialectics. Of the four, Lambert's work is the best example of question-summas that proceed principally by asking and (...) answering questions on the subject matter. Thomas S. Maloney's translation of Logica, the only complete translation of this work in any language, is a milestone in the study of medieval logic. More than simply a translation, Maloney's project is a critical, comprehensive study of Lambert's logic situated in the context of his contemporaries and predecessors. As such, it offers a wealth of annotation and commentary. The lengthy introduction and extensive notes to the text explain the origin, theoretical context, and intricacies of the text and its doctrines. Maloney also addresses the disputed issues of authorship, date, and place of publication of the Summa Lamberti and makes available to the English-only audience the French, German, and Italian secondary sources--all translated--that are needed to enter the discussion. "Thomas S. Maloney fully commands the primary and secondary sources necessary to elucidate Lambert's Logica. An expert on Roger Bacon's philosophy, he demonstrates a rare proficiency in medieval Latin and scholastic logic. His references to sources from the ancient (Aristotle and Boethius) and medieval worlds are apposite, perspicuous, and useful. The volume's presentation with an appropriate introduction and commentary in the endnotes will no doubt establish it as an indispensable resource for scholars in the twenty-first century." --Alan Perreiah, University of Kentucky. (shrink)

This book marks the inauguration of the Historia Logicae book series, which seeks to publish high-quality monographs, dissertations, textbooks, proceedings, and anthologies on the history of logic in either German or English. Serving as the inaugural volume in this series, the book explores the contemporary interpretation of logic across many centuries and cultures. The first section of the volume comprises a compilation of papers dedicated to ancient and medieval logic, examining prominent thinkers such as Plato, Aristotle, Seneca, Porphyry, Proclus, Boethius, (...) Buridan, and Kilwardby. The second section shifts focus towards early-modern and contemporary logics, including the works of Caramuel, Kant, Drobisch, Husserl, and Jaskowski. Topics of discussion encompass the relationship between mathematics and logic, natural deduction, intuitionism, graph theory, categorical judgments, theories of truth, modal logic, opposition relations, logic diagrams, definitions of formal logic, many-sorted logic, model theory, and paraconsistent logic. (shrink)

[1. Without special title] -- [2]. Anastatica.

Else Margarete Barth (1928-2015) was een Noors-Nederlandse filosoof.0Else Barth vond dat filosofie in dienst zou moeten staan van de combinatie van medemenselijkheid en helder, geïnformeerd denken en discussiëren. Barth was ervan overtuigd dat zorgvuldig redeneren en debatteren noodzakelijk is voor het verbeteren van menselijke relaties. Met logica als wapen bestreed ze vaagheid en vooroordelen. Om logica van betekenis te maken voor het praktische leven, verbond ze het met analytisch onderzoek naar ideeën die rondwaren in wetenschap en politieke cultuur. (...) Haar bijzondere belangstelling ging daarbij uit naar anti-argumentatieve en anti-parlementaire houdingen en denksystemen die, vaak ten faveure van een hoger doel, minachting voor (groepen) individuen legitimeren of zelfs aanmoedigen. Met haar pleidooi voor een 'empirische logica' leverde Barth een originele bijdrage aan de Europese wijsbegeerte, die ook voor de huidige tijd relevant is.0'Empirische logica' is een selectie uit Barths werk. De bundel bevat voorbeelden van toegepast empirisch-logisch onderzoek, naar de logische grondslagen van het Duitse idealisme bijvoorbeeld, die volgens Barth dezelfde zijn als die van de klassieke homeopathie, naar het denken van de Noorse nazi Quisling, maar ook naar de onevenredige aandacht voor 'gemiddelden' in de sociale wetenschappen, die tot stigmatisering leidt. In beschouwende stukken reflecteert de auteur onder meer op het belang van cultuur-georiënteerd logica-onderwijs en zoekt ze een verklaring voor de kloof tussen logica en politiek. Ten slotte zijn essays0opgenomen die Barth schreef over filosofen die haar inspireerden: Bertrand Russell, Evert Willem Beth en Arne Naess. (shrink)

Objetivamos elaborar um balanço sobre lógica das perguntas científicas na produção do conhecimento stricto sensu. Tomamos como fontes 100 dissertações e 32 teses escritas por docentes que trabalham em cursos de Educação Física no Estado da Bahia – 1982 a 2018, abordando enquanto objeto a lógica instituída pelas perguntas científicas na referida produção. Trata-se de uma pesquisa documental, tendo como método o materialismo histórico e dialético. Os resultados apontam que 48% das produções têm suas perguntas de investigação construída a partir (...) da lógica formal; 28% apresenta uma lógica dialética na elaboração das perguntas científicas; e 24% não apresentam problema de investigação. (shrink)

Nel suo pionieristico lavoro Conditions in Königsberg and the Making of Kant's Philosophy, Giorgio Tonelli lamentava l'assenza di un'indagine approfondita sul contesto intellettuale di Königsberg e sull'eventuale influenza che esso esercitò su alcuni aspetti del pensiero di Kant. Questo libro vuole colmare questa lacuna prestando particolare attenzione alla tradizione aristotelica, alla Schulphilosophie, e alla corrente dell'eclettismo, che dominarono l'ambiente regiomontano sino all'avvento della filosofia critica kantiana. Il lavoro mostra come dai fallimenti dei progetti logici e metafisici precritici, legati alle influenze (...) ricevute dall'ambiente di Königsberg, Kant abbia tratto le idee e gli spunti per la stesura della Kritik der reinen Vernunft. (shrink)