In earlier work, I have presented an interpretation of Obligationes as logical games of consistency maintenance; this interpretation has some advantages, in particular that of capturing the multi-agent, goal-oriented, rule-governed nature of the enterprise by means of the game analogy. But it has as its main limitation the fact that it does not provide a satisfactory account of the deontic aspect of the framework—i.e. of what being obliged to a certain statement consists in. In order to remedy this shortcoming, (...) this paper argues for the more encompassing thesis that Obligationes can be viewed as a theory of rational dialogical practices, in particular concerning the management of one's discursive commitments. The main inspiration for this interpretation comes from R. Brandom's inferentialist, normative pragmatism, but more generally, it relies heavily on a dialogical conception of logic. I argue that it offers a more compelling account of several aspects of the obligational framework, in particular the role of doubting responses and the ubiquity of obligational vocabulary in the context of scientific discourse in the medieval tradition. (shrink)

I argue that the medieval form of dialectical disputation known as obligationes can be viewed as a logical game of consistency maintenance. The game has two participants, Opponent and Respondent. Opponent puts forward a proposition P; Respondent must concede, deny or doubt, on the basis of inferential relations between P and previously accepted or denied propositions, or, in case there is none, on the basis of the common set of beliefs. Respondent loses the game if he concedes a contradictory (...) set of propositions. Opponent loses the game if Respondent is able to maintain consistency during the stipulated period of time. The obligational rules are here formalised by means of familiar notational devices, and the application of some game-theoretical concepts, such as (winning) strategy, moves, motivation, allows for an analysis of some crucial properties of the game. In particular, the primacy of inferential (syntactic) relations over semantic aspects and the dynamic character of obligations are outlined. (shrink)

This paper defends the thesis that the mediaeval genre of logical treatises De obligatiombus contained a theoretical account of counterfacutal reasoning, perhaps the first such account in the history of philosophy. This interpretation helps to explain some of the theoretical disputes in the obligationes literature in the first half of the fourteenth century. Section 1 is introductory. Section 2 presents Walter Burley's theory, while section 3 argues for the counterfactual interpretation of obligationes and section 4 discusses difficulties with (...) Burley's theory. Section 5 presents the textual basis for Richard Kilvington's theory, and section 6 outlines that theory. Section 7 discusses Roger Swyneshed's theory. Section 8 contains a summary and conclusion. (shrink)

L'ed. delle Obligationes si basa su quattro mss.: Praha, Knihovni Metropolitni Kapituly, M.CXLV ; Oxford, New College, E 289 ; Praha, Státní Knihóvna CSR, VIII E 11 ; Salamanca, Biblioteca de la Universidad, 2358 . Nell'introduzione l'A. prende in esame la tradizione manoscritta delle opere di Giovanni Tarteys, fornendo anche una breve notizia biografica di questo magister artium attivo ad Oxford tra la fine del Trecento e gli inizi del Quattrocento. Segue un'analisi comparata del De Obligationibus di Giovanni con (...) le trattazioni analoghe di altri maestri, tra i quali Rodolfo Strode, Gualterio Burley, Paolo da Venezia e Giovanni Wyclif. Discussi infine i criteri di edizione. (shrink)

The history of the mediaeval obligationes-literature has only recently begun to be studied. Two important treatises in this literature, one by Walter Burley and the other attributed to William of Sherwood, have been edited by Romuald Green in a forthcoming book. But there is considerable doubt concerning the authenticity of the text attributed to Sherwood. The correct attribution and dating of this treatise is crucial for our understanding of the history of this literature. In this paper, we argue that (...) the treatise is not as early as William of Sherwood, that on the contrary it dates no earlier than the very end of the thirteenth century, and that, although there is some contrary evidence, the treatise may be an early work by Walter Burley himself. (shrink)

In what follows, I analyze Ralph Strode's treatise on obligations. I have used a hitherto unpublished edition of the text (based on 14 manuscripts) made by Prof. E.J. Ashworth. I first give a brief description of Strode's text, which is all the more necessary given that it is not available to the average reader; I also offer a reconstruction of the rules proposed by Strode, following the style of reconstruction used in my analysis of Burley's and Swyneshed's rules elsewhere—that is, (...) essentially based on the idea that obligationes can be viewed as logical games. In the second part, I address Strode's explicit arguments contra Swyneshed. In the third part, I discuss Strode's epistemic and pragmatic approach to obligationes. (shrink)

In [Dutilh Novaes, Medieval-obligations as logical Games of Consistency maintenance, synthese, (2004)], I proposed a reconstruction of Walter Burley’s theory of obligationes, based on the idea that Burley’s theory of obligationes could be seen as a logical game of consistency maintenance. In the present paper, I intend to test the game hypothesis on another important theory of obligationes, namely Roger Swyneshed’s theory. In his treatise on obligationes [edited by P.V. Spade, cf. Spade History and philosophy of (...) Logic 3(1982) 1-32], Swyneshed introduced significant modifications to the general framework of obligationes. To compare the two theories, I apply the same formal apparatus used in the previous paper. It will become patent that Swyneshed’s theory is considerably different from Burley’s, among other reasons because the dynamic aspects that play a major role in the latter are simply not present in the former. My conclusion is that Swyneshed’s version of obligationes is not directed towards consistency maintenance, but rather towards inference recognition, and that it is, from a game-theoretical perspective, less interesting a theory than Burley’s. (shrink)

In [Dutilh Novaes, Medieval-obligations as logical Games of Consistency maintenance, synthese, (2004)], I proposed a reconstruction of Walter Burley’s theory of obligationes, based on the idea that Burley’s theory of obligationes could be seen as a logical game of consistency maintenance. In the present paper, I intend to test the game hypothesis on another important theory of obligationes, namely Roger Swyneshed’s theory. In his treatise on obligationes [edited by P.V. Spade, cf. Spade History and philosophy of (...) Logic 3(1982) 1-32], Swyneshed introduced significant modifications to the general framework of obligationes. To compare the two theories, I apply the same formal apparatus used in the previous paper. It will become patent that Swyneshed’s theory is considerably different from Burley’s, among other reasons because the dynamic aspects that play a major role in the latter are simply not present in the former. My conclusion is that Swyneshed’s version of obligationes is not directed towards consistency maintenance, but rather towards inference recognition, and that it is, from a game-theoretical perspective, less interesting a theory than Burley’s. (shrink)

In the early 1980s, Paul V. Spade advanced the thesis that obligational reasoning was counterfactual reasoning, based upon his interpretation of the obligationes of Walter Burley, Richard Kilvington, and Roger Swyneshed. Eleonore Stump in a series of contemporary papers argued against Spade’s thesis with respect to Burley and Swyneshed, provisionally admitting it for Kilvington with the caveat that Kilvington’s theory is by no means clear or non-idiosyncratic. In this paper, we revisit the connection between counterfactual reasoning and obligationes, (...) focusing on one particular treatise, the anonymous early twelfth-century Obligationes Parisienses edited by L.M. de Rijk in the late 70s. We show that while positio in this treatise does not involve counterfactual reasoning, the species sit verum or rei veritas apparently does, and it is precisely this which distinguishes the two species in this treatise. (shrink)

This book presents novel formalizations of three of the most important medieval logical theories: supposition, consequence and obligations. In an additional fourth part, an in-depth analysis of the concept of formalization is presented - a crucial concept in the current logical panorama, which as such receives surprisingly little attention.Although formalizations of medieval logical theories have been proposed earlier in the literature, the formalizations presented here are all based on innovative vantage points: supposition theories as algorithmic hermeneutics, theories of consequence analyzed (...) with tools borrowed from model-theory and two-dimensional semantics, and obligations as logical games. For this reason, this is perhaps the first time that these medieval logical theories are made fully accessible to the modern philosopher and logician who wishes to obtain a better grasp of them, but who has always been held back by the lack of appropriate ‘translations' into modern terms.Moreover, the book offers a reflection on the very nature of logic, a reflection that is prompted by the comparisons between medieval and modern logic, their similarities and dissimilarities. It is thus a contribution not only to the history of logic, but also to the philosophy of logic, the philosophy of language and semantics.The analysis of medieval logic is also relevant for the modern philosopher and logician in that, being the unifying methodology used across all disciplines at that time, logic really provided unity to science. It thus presents a unified model of scientific investigation, where logic plays the aggregating role. (shrink)

J'examine plusieurs sources selon lesquelles Swyneshed (malgré les prétentions d'Angel D'Ors dans ses articles récents) donne une nova responsio en partie sous forme de la règle « On peut nier une proposition conjonctive après avoir concédé ses deux parties. » Je montre que cette nova responsio est liée à un rejet de la règle « Chaque proposition qui suit de l'ensemble de propositions déjà concédées doit être concédée », et j'attribue ce rejet à une théorie selon laquelle une inférence se (...) base sur le rapport logique entre seulement deux propositions. I examine a number of sources according to which Swyneshed (despite the claims made by Angel D'Ors in his recent articles) does give a nova responsio partly in the form of the rule « One can deny a conjunction whose conjuncts have already been granted. » I show that this nova responsio is linked to a rejection of the rule « Every proposition following from a set of propositions which have already been granted must be granted », and I attribute this rejection to a theory whereby an inference is based on the logical relations between just two propositions. (shrink)

_ Source: _Volume 53, Issue 2-4, pp 372 - 390 This paper investigates a series of Oxford _Obligationes_ texts, all of which can be associated with Richard Billingham. My study is based on eleven of the surviving manuscripts and two early printed texts. I focus on one aspect of their discussion, namely the rule for granting the initial _positum_ of an obligational disputation of the type called _positio_, and the six restrictions that could be placed on that rule. I explain (...) these restrictions with reference to several sophismata that were meant to illustrate the problems that the restrictions were intended to solve, and in particular, I discuss the fifth restriction ‘not inconsistent with the _positum_’. I also shed light on the final restriction, which has not always been well understood, namely the restriction ‘wherever there is no _obligatio_ relevant to the _positum_’. (shrink)

In this paper I will examine the relation between the theory of obligations and its use in sophismatic contexts through the lens of certain pragmatic concerns. In order to do this, I will take a sophism discussed by Peter of Mantua in his treatise on obligations as a case-study. I will first provide a brief outline of the structure of the treatise and then examine a concrete case that shows how the relationship between background assumptions (casus and context of utterance) (...) and criteria of response seems to suggest a way to qualify the application of general rules (especially for irrelevant sentences) in certain limit-cases. By discussing Peter's presentation of the sophism, I will also argue for a connection between Peter of Mantua's text and Mesino de Codronchi's Questiones on the De Interpretatione. (shrink)

The manuscript Venice, Biblioteca Nazionale Marciana, Class XI n. 12, Zanetti Latini 301 (= 1576), contains on fols. 1r–24v a seemingly unique copy of a series of fifteen logical questions, ten on obligationes and the remaining five on insolubilia.1 The series on obligationes is untitled and unattributed in the manuscript, but the questions on insolubilia begin (fol. 18r11) “Incipiunt quaestiones super insolubilibus,” and are attributed at the end to a certain John of Wesel (fol. 24v41): “Ergo expletae sunt (...) quaestiones insolubilium a Johanne de Vesalia Parixius2 disputatae. Deo gratias. Amen.”. (shrink)

The overarching aim of this excellent book is to demonstrate the common ground between medieval logic and logical theories of the twentieth century by analyzing some important medieval approaches to three important topics in medieval logic and then showing that in each case, once we determine what is really going on in the medieval theory, it can be formalized in such a way as to show how it resembles one or more developments in twentieth-century logical theory. Analysis in terms of (...) modern logical theory has a lot to offer the study of medieval logical theories, the author claims, and twentieth-century theory can learn some interesting lessons from examining its medieval counterparts. Much of the material in these specific discussions has been presented in earlier versions in the author's published articles. "The Philosophy of Formalization" , however, is new. English translations are used in the text, though the Latin is supplied in the footnotes. (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)

Formal dialogue systems model rule-based interaction between agents and as such have multiple applications in multi-agent systems and AI more generally. Their conceptual roots are in formal theories of natural argumentation, of which Hamblin’s formal systems of argumentation in Hamblin (Fallacies. Methuen, London, 1970, Theoria 37:130–135, 1971) are some of the earliest examples. Hamblin cites the medieval theory of obligationes as inspiration for his development of formal argumentation. In an obligatio, two agents, the Opponent and the Respondent, engage in (...) an alternating-move dialogue, where the Respondent’s actions are governed by certain rules, and the goal of the dialogue is establishing the consistency of a proposition. We implement obligationes in the formal dialogue system framework of Prakken (Knowl Eng Rev 21(2):163–188, 2006) using Dynamic Epistemic Logic (van Ditmarsch et al. in Dynamic epistemic logic, Synthese Library Series. Springer, Berlin, 2007). The result is a new type of inter-agent dialogue, for consistency-checking, and analyzing obligationes in this way also sheds light on interpretational and historical questions concerning their use and purpose in medieval academia. (shrink)

The paper considers two kinds of medieval obligational disputations and the medieval genre of sophismata in relation to the kinds of inferences accepted in them. The main texts discussed are the anonymous Obligationes parisienses from the early 13th century and Richard Kilvington’s Sophismata from the early 14th century. Four different kinds of warranted transition from an antecedent to a consequent become apparent in the medieval discussions: the strong logical validity of basic propositional logic, analytic validity based on conceptual containment, (...) merely semantic impossibility of the antecedent being true without the consequent, and intuitively true counterfactual conditionals. As these different kinds of consequences are spelled out by means of obligational disputations, it appears that the genre of obligations is indeed useful for the “knowledge of consequences,” as the anonymous Obligationes parisienses claims. (shrink)

v. 1. De natura legis -- v. 2. De legis obligatione -- v. 3. De lege naturali -- v. 4. De iure gentium -- v. 5. De civili potestate -- v. 6. De politica obligatione -- v. 7-8. De lege positiva canonica.

The problem of logical omniscience breaks down to the problems of the closure of knowledge under implication and of the distribution of knowledge over implication. In late medieval scholasticism these two related issues were engaged in various genres, in particular in general analysis of validity, games of obligationes, solution to self-referential antinomies and semantics of terms. The present study analyses the corpus of fourteenth-century texts with some overreaches to the subsequent two centuries, attempting to cover representatives of both the (...) “British” and the “Continental” tradition. With some degree of simplification, this results in a range of four basic positions: 1. knowledge is closed under “analytic entailment” (Buridan), 2. knowledge distributes over implication (Heytesbury), 3. knowledge distributes over implication provided that its consequent’s truth is being taken into consideration (Peter of Mantua), 4. knowledge does not distribute overimplication (Wyclif). (shrink)

This edited volume presents new lines of research dealing with the language of thought and its philosophical implications in the time of Ockham. It features more than 20 essays that also serve as a tribute to the ground-breaking work of a leading expert in late medieval philosophy: Claude Panaccio. Coverage addresses topics in the philosophy of mind and cognition (externalism, mental causation, resemblance, habits, sensory awareness, the psychology, illusion, representationalism), concepts (universal, transcendental, identity, syncategorematic), logic and language (definitions, syllogisms, modality, (...) supposition, obligationes, et cetera), action theory (belief, will, action), and more. A distinctive feature of this work is that it brings together contributions in both French and English, the two major research languages today on the main theme in question. It unites the most renowned specialists in the field as well as many of Claude Panaccio's former students who have engaged with his work over the years. In furthering this dialogue, the essays render key topics in fourteenth-century thought accessible to the contemporary philosophical community without being anachronistic or insensitive to the particularities of the medieval context. As a result, this book will appeal to a general population of philosophers and historians of philosophy with an interest in logic, philosophy of language, philosophy of mind, and metaphysics. (shrink)

In the first half of the fifteenth century, the Italian logician, natural philosopher, and doctor of medicine Cajetan of Thiene wrote a commentary on William Heytesbury’s Regulae solvendi sophismata, which later became a part of the printed edition of Heytesbury’s treatises. Several late fifteenth century reprints sustained its circulation and further influence. Following Heytesbury, Cajetan listed four alternative treatments of paradoxes, where the first three were formulated in general logico-semantic terms and the last one in terms of obligationes. The (...) present analysis reconstructs the first three positions in terms of the theories of logical operators endorsed as part of the solution to paradoxes. This reconstruction uncovers different underlying views of operators, namely context-sensitive, value-functional, and supervaluationist.Priore dimidia parte saeculi 15 Caietanus de Thiena, logicus, physicus et medicus, commentarium super G. Hentisberi Regulis solvendi sophismata conscripsit, quod posterius una cum Hentisberi tractatibus typis impressum est. Cuius commentarii notitiam auctoritatemque continuam iteratae nonnullae eius editiones in fi ne 15 saeculi factae sustinebant. Caietanus quattuor vias tractandi insolubilia distinxit, quarum tres primae conceptibus generalibus logico-semanticis, quarta doctrina de obligationibus innixae sunt. In analysi hic proposita auctor primas tres vias reconstruit, doctrinas varias de logicis coniunctionibus vel notis reserans, super quibus illae viae solvendi paradoxa fundantur. Quarum prima vim notarum a contextu sermonis dependentem facit. Altera notas pure “compositionaliter” tractat. Tertia iuxta modum doctrinae de “supervaluatione” omnes formales tautologias servat, aliis considerationibus neglectis. (shrink)

The article is concerned with the account of Aristotle's theory of disputation given by Robert Kilwardby in his commentary, composed in Paris during the 1240s, on Aristotle's Prior Analytics. Specifically, I show that Kilwardby covers demonstrative as well as dialectical disputations, and gives an elementary account of the rules governing such disputations, in their adversarial forms as well as in an idealized form where the interlocutors engage in a cooperative activity. I describe the resemblances and the differences between disputations as (...) theorized by Kilwardby and the game of obligationes as understood by some of his contemporaries. (shrink)

The current trend in knowledge revision in the Dynamic Epistemic Logic tradition focuses on the addition of new knowledge, rather than the possibility of losing knowledge. Yet there are natural situations, such as an agent who does not want another agent to know that she knows a certain piece of information, where there is a need to be able to model the retraction of a proposition from a knowledge base. One situation where this is systematically required is the variant of (...) the medieval theory of obligationes known as dubitatio, where one of the agents in the dialogue is obliged to hold the initial proposition, the dubitatum, as doubtful, regardless of what other propositions she may concede or deny during the disputation. In this paper, we use dubitatio as a motivation for studying deceitful agents, and we discuss various ways that an agent can move from a model where f is known to one where f is not known. (shrink)

'This sentence is false' - is that true? The 'Liar paradox' embodied in those words exerted a particular fascination on the logicians of the Western later Middle Ages, and, along with similar 'insoluble' problems, forms the subject of the first group of articles in this volume. In the following parts Professor Spade turns to medieval semantic theory, views on the relationship between language and thought, and to a study of one particular genre of disputation, that known as 'obligationes'. The (...) focus is on the Oxford scholastics of the first half of the 14th century, and it is the name of William of Ockham which dominates these pages - a thinker with whom Professor Spade finds himself in considerable philosophical sympathy, and whose work on logic and semantic theory has a depth and richness that have not always been sufficiently appreciated. (shrink)

Il volume intende presentare in una prospettiva organica la letteratura medievale sugli Insolubilia. Gli insolubili sono stati definiti come proposizioni autoreferenziali che hanno origine direttamente dalla tradizione del paradosso del mentitore. L’impostazione del presente lavoro vuole essere sia filologica che teorica in modo che da un lato si possano inserire le analisi speculative sugli Insolubilia in un contesto critico–storico più ampio che restituisca la peculiarità della trattazione medievale, e dall’altro, possa essere effettuata una analisi precisa dei tentativi di soluzione proposti (...) anche attraverso gli strumenti della logica moderna (quando possibile e non fuorviante). (shrink)