The recovery of Aristotle’s logic during the twelfth century was a great stimulus to medieval thinkers. Among their own theories developed to explain Aristotle’s theories of valid and invalid reasoning was a theory of consequence, of what arguments were valid, and why. By the fourteenth century, two main lines of thought had developed, one at Oxford, the other at Paris. Both schools distinguished formal from material consequence, but in very different ways. In Buridan and his followers in (...) Paris, formal consequence was that preserved under uniform substitution. In Oxford, in contrast, formal consequence included analytic consequences such as ‘If it’s a man, then it’s an animal’. Aristotle’s notion of syllogistic consequence was subsumed under the treatment of formal consequence. Buridan developed a general theory embracing the assertoric syllogism, the modal syllogism and syllogisms with oblique terms. The result was a thoroughly systematic and extensive treatment of logical theory and logical consequence which repays investigation. (shrink)

The word "modem" in the title of this book refers primarily to post-medieval discussions, but it also hints at those medieval mo dal theories which were considered modem in contradistinction to ancient conceptions and which in different ways influenced philosophical discussions during the early modem period. The me dieval developments are investigated in the opening paper, 'The Foundations of Modality and Conceivability in Descartes and His Predecessors', by Lilli Alanen and Simo Knuuttila. Boethius's works from the early (...) sixth century belonged to the sources from which early medieval thinkers obtained their knowledge of ancient thought. They offered extensive discus sions of traditional modal conceptions the basic forms of which were: (1) the paradigm of possibility as a potency striving to realize itself; (2) the "statistical" interpretation of modal no tions where necessity means actuality in all relevant cases or omnitemporal actuality, possibility means actuality in some rel evant cases or sometimes, and impossibility means omnitemporal non-actuality; and (3) the "logical" definition of possibility as something which, being assumed, results in nothing contradic tory. Boethius accepted the Aristotelian view according to which total possibilities in the first sense must prove their met tle through actualization and possibilities in the third sense are assumed to be realized in our actual history. On these presump tions, all of the above-mentioned ancient paradigms imply the Principle of Plenitude according to which no genuine possibility remains unrealized. (shrink)

During the 13th century, several logicians in the Latin medieval tradition showed a special interest in the nature of impossibility, and in the different kinds or ‘degrees’ of impossibility that could be distinguished. This discussion resulted in an analysis of the modal concept with a fineness of grain unprecedented in earlier modal accounts. Of the several divisions of the term ‘impossible’ that were offered, one became particularly relevant in connection with the debate on ars obligatoria and positio impossibilis: the (...) distinction between ‘intelligible’ and ‘unintelligible’ impossibilities. In this article, I consider some 13th-century tracts on obligations that provide an account of the relation between impossibility and intelligibility and discuss the inferential principles that are permissible when we reason from an impossible – but intelligible – premise. I also explore the way in which the 13th-century reflection on this topic survives, in a revised form, in some early 14th-century accounts of positio, namely, those of William of Ockham, Roger Swineshead and Thomas Bradwardine. (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)

A Critical Introduction to the Metaphysics of Modality examines the eight main contemporary theories of possibility behind a central metaphysical topic. Covering modal skepticism, modal expressivism, modalism, modal realism, ersatzism, modal fictionalism, modal agnosticism, and the new modal actualism, this comprehensive introduction to modality places contemporary debates in an historical context. Beginning with a historical overview, Andrea Borghini discusses Parmenides and Zeno; looks at how central Medieval authors such as Aquinas, and Buridan prepared the ground for the Early (...) Modern radical views of Leibniz, Spinoza, and Hume and discusses advancements in semantics in the later-half of the twentieth century a resulted in the rise of modal metaphysics, the branch characterizing the past few decades of philosophical reflection. Framing the debate according to three main perspectives - logical, epistemic, metaphysical- Borghini provides the basic concepts and terms required to discuss modality. With suggestions of further reading and end-of-chapter study questions, A Critical Introduction to the Metaphysics of Modality is an up-to-date resource for students working in contemporary metaphysics seeking a better understanding of this crucial topic. (shrink)

Originally published in 1993, Modalities in Medieval Philosophy looks at the idea of modality as multiplicity of reference with respect to alternative domains. The book examines how this emerged in early medieval discussions and addresses how it was originally influenced by the theological conception of God acting by choice. After a discussion of ancient modal paradigms, the author traces the interplay of old and new modal views in medieval logic and semantics, philosophy and theology. A detailed (...) account is given of late medieval discussions of the new modal logic, epistemic logic, and the logic norms. These theories show striking similarities to some basic tenets of contemporary approaches to modal matters. This work will be of considerable interest to historians of philosophy and ideas and philosophers of logic and metaphysics. (shrink)

In the last 30 years there has been growing interest in and a greater appreciation of the unique contributions that medieval authors have made to the history of logic. In this thesis, we compare and contrast the modal logics of Robert Kilwardby and John Buridan and explore how their two conceptions of modality relate to and differ from modern notions of modal logic. We develop formal reconstructions of both authors' logics, making use of a number of different formal techniques. (...) In the case of Robert Kilwardby we show that using his distinction between per se and per accidens modalities, he is able to provide a consistent interpretation of the apodictic fragment of Aristotle's modal syllogism and that, by generalising this distinction to hypothetical construction, he can develop an account of connexive logic. In the case of John Buridan we show that his modal logic is a natural extension of the usual Kripke-style possible worlds semantics, and that this modal logic can be shown to be sound and complete relative to a proof-theoretic formalisation of Buridan's treatment of the expository syllogism. (shrink)

Descartes's view of modality is analyzed by contrast to two earlier models: the ancient realist one, defended by Boethius, where possibility and necessity are connected to natural potency, and the modern intensionalist one, which dissociates necessary and possible truths from any ontological foundation, treating them as conceptual, a priori given preconditions for any intellect. The emergence of this view is traced from Gilbert of Poitiers to duns Scotus, Ockham and Suarez. The Cartesian theory of the creation of eternal truths, it (...) is argued, involves a rejection of this idea of absolute conceivability and can be seen as a constructivist view of intelligibility and rationality. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Journal of the History of Ideas 62.1 (2001) 121-140 [Access article in PDF] The Rhetoric of Modal Equivocacy in Cartesian Transubstantiation Julian Bourg Everyday language, in which words are not defined, is a medium in which nobody can express himself unequivocally. Robert Musil 1René Descartes's attempt to explain Eucharistic transubstantiation has long been understood as a dramatically significant moment in his tightrope walk across the medieval-to-modern divide. 2 (...) Modeled on the Last Supper in the New Testament, the Eucharistic rite had been explained in the Catholic tradition after the twelfth century in the scholastic philosophical language of substance and accident. 3 As the Council of Trent reaffirmed in 1551, this transubstantiation was a conversion "of the whole substance of the bread into the substance of the Body and of the whole substance of the wine into the substance of His blood... the appearances [speciebus] only of the bread and wine remaining." 4 Christ was [End Page 121] held to be "truly, really, and substantially contained under the species of those sensible things," under what still appeared to be bread and wine. 5Descartes's dilemma was that on one hand he was dead set against the hylomorphic theory of substance and accident, and on the other hand he found himself obliged by some of his interlocutors to comment on transubstantiation. It was a balancing act that pleased no one for very long, since despite his sometimes eager discussions of the Eucharist, he was not, as he admitted, "a theologian by profession." 6 The putative heterodoxy of Cartesian transubstantiation was principally responsible for his works being placed on the Index of Prohibited Books in 1663 and for his thought being banned from schools under Louis XIV in 1671. 7 His treatment of the Eucharistic question also distressed others in the seventeenth and early eighteenth centuries, such as Thomas Hobbes and Isaac Newton, who were unhappy that Descartes had bothered with such a theological non-issue. 8 For the many post-seventeenth-century advocates of a proto-secular Descartes as the godfather of modern philosophy, Cartesian transubstantiation has proved similarly inconvenient.The indisputable connections between Descartes and his scholastic forerunners, exemplified by the Eucharistic question, service a basic question of contemporary Cartesian scholarship. As Émile Boutroux put it, how was new wine poured from old bottles? 9 Accepting as axiomatic that there was something both radical and original in the Cartesian project but without falling back on pieties about his turn toward the modern subject, we must ask how Descartes put forth novel claims in conceptual language regarded by his contemporaries as resonant, if not consonant, with the scholastic intellectual culture of Catholic Reform France. More precisely, setting aside the not-very-defensible position that such language was merely incidental to Cartesian thought (a position that dehistoricizes Descartes as a precocious Enlightener), the dilemma then becomes explaining how original positions were elaborated within scholastic language. One important task is accounting for what Descartes did with that vocabulary--how he pointed words and concepts in new and surprising directions. The Eucharist becomes crucial in this perspective. [End Page 122]Though the question of Cartesian transubstantiation has been discussed for some time, the topic is worth revisiting again in light of two themes, rhetoric and the Cartesian theory of modes. My argument is that Descartes used one particular scholastic term, "mode," in equivocal ways and that this equivocation was in multiple senses rhetorical. This rhetoric coalesced and came to the fore around the Eucharist because, given the intellectual-political climate of the Catholic Reformation, the stakes of transubstantiation were so high. That Descartes used certain scholastic terms in equivocal or ambiguous ways should come as no surprise. Of interest, though, is the fact that by definition "mode" meant many things. This ambiguous term facilitated ambiguous intellectual positions about the Eucharist that allowed Descartes more generally (no matter what he "really" intended) to skirt between an orthodoxy that represented the past and an originality, not without dangers in his time, that seem to gesture toward our day. Foregrounded with regard to... (shrink)

Medieval Modal Logic & Science uses modal reasoning in a new way to fortify the relationships between science, ethics, and politics. Robert C. Trundle accomplishes this by analyzing the role of modal logic in the work of St. Augustine and St. Thomas Aquinas, then applying these themes to contemporary issues. He incorporates Augustine's ideas involving thought and consciousness, and Aquinas's reasoning to a First Cause. The author also deals with Augustine's ties to Aristotelian modalities of thought regarding science (...) and logic, reassessing the commonly held belief in Augustine's Platonism to not be a mistake as much as a simplistic view of his philosophy. Trundle links contemporary issues in epistemology, morality, theology, and logic, making several useful connections between ancient and medieval studies in modal logic and modern concerns. These applications of modal theory illuminate many puzzles in the works of Heidegger, Wittgenstein, Whitehead, and Kuhn. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Avicenna's Theory of Science: Logic, Metaphysics, Epistemology by Riccardo StrobinoThérèse-Anne DruartRiccardo Strobino. Avicenna's Theory of Science: Logic, Metaphysics, Epistemology. Oakland: University of California Press, 2021. Pp. xvi + 428. Hardback, $95.00.Strobino's remarkable book does not simply present Avicenna's theory of science; it also highlights the importance of demonstration not only for logic but also for metaphysics and epistemology. Hence, Strobino's work is essential to appreciate and better understand (...) Avicenna's philosophy as a whole.Strobino grounds his research on Avicenna's theory of science in his Book of Demonstration in the Shifā', which focuses on Aristotle's Posterior Analytics. Taking into account the lack of any translation into English or any other main modern language as well as the lack of a full medieval Latin translation (only chapter 7 of book 3 exists in a medieval Latin version) of Avicenna's text, Strobino kindly provides in appendix C (357–71) a detailed "map" of this text, useful not only to readers who cannot handle Arabic but even to those who can, as the [End Page 326] text is so rich and complex. A simple but careful look at this map confirms what Strobino makes clear and insists upon: Avicenna greatly develops, enriches, completes, and even outgrows some of Aristotle's views. The Book of Demonstration is far more than a commentary on the Posterior Analytics; it is a complete reworking of it.Strobino shows that Avicenna grounds his theory of demonstration and science on two basic notions—conception (tasawwur) and assertion (tasdīq, which some other scholars translate as "assent")—and so gives a unified approach to his theory. Scientific conceptions require better understanding of definition and description. Avicenna builds definitions and descriptions on essentialism and, therefore, grounds them in metaphysics. As for scientific assertions, in contradistinction to nonscientific ones, they must be necessary and give the cause. Therefore, Avicenna places great importance on modality and develops modal syllogisms, whereas Aristotle focused on categorical syllogisms and neglected hypothetical and disjunctive syllogisms. Avicenna also elaborates a sophisticated account of modality and its metaphysical implications. Furthermore, he broadens and enriches the appreciation of causality and explanation. These developments, according to Strobino, lead Avicenna to set forth an intricate division and hierarchy of the sciences under metaphysics, which provides their ultimate principles and allows for a unified understanding of the sciences while respecting their particularities.According to Strobino, Avicenna is keen to develop a theory of science that gives a good account of science as it is practiced. Strobino carefully shows how Avicenna's theory better reflects this practice than does Aristotle's.Strobino does not simply highlight how much Avicenna distances himself from Aristotle and goes far beyond what the Posterior Analytics yields, but also shows how much Avicenna relies on points adumbrated by his predecessor al-Fārābī in his own Book of Demonstration.The way Strobino through his analysis of demonstration links Avicenna's understanding of logic, epistemology, and metaphysics underscores the coherence and unity of Avicenna's philosophy. Scholars were aware of the importance of demonstration for Avicenna in various philosophical fields, but until the release of this book, they seemed not to have fully grasped the centrality and essential role played by the Avicennian understanding and focus on demonstration.Of course, Strobino does not limit himself to an analysis of passages in the Book of Demonstration. He has an encompassing knowledge of Avicenna's texts and uses them well to flesh out and enrich what remains terse in the Book of Demonstration. He even takes into account the way one of his successors, al-Tūsī, reads him. He also shows an extensive and wide-ranging knowledge of Aristotle's texts and of Aristotelian scholarship, as well as an interest in the Greek commentators and Galen and their relevance for interpreting Avicenna.Avicenna's Theory of Science is not an easy book to read, as it is often very technical, particularly when dealing with purely logical points or issues, but reading it is rewarding if one does so slowly and meditatively. The author, in fact, illuminates difficult matters but does not waste words. From... (shrink)

There is often said to be something peculiar about the history of modal theory up until the turn of the fourteenth century, when John Duns Scotus decisively reframed the issues. I wish to argue that this impression of dramatic discontinuity is almost entirely a misimpression. Premodern philosophers prescind from the wide-open modal space of all possible worlds because they seek to adapt their modal discourse to the explanatory and linguistic demands of their context.

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:The Medieval Heritage in Early Modern Metaphysics and Modal Theory, 1400–1700Jean-Pascal AnfrayRussell L. Friedman and Lauge O. Nielsen, editors. The Medieval Heritage in Early Modern Metaphysics and Modal Theory, 1400–1700. Dordrecht: Kluwer, 2003. Pp. vi + 346. Cloth, $149.00.This volume contains contributions that aim to show the continuity between late medieval thought and early modern philosophy, or, as the editors say, to investigate "the way (...) that medieval thought served as a fertile basis for developments in the early modern period" (3). As the title indicates, most papers treat topics more or less connected to modalities, either from a logical or from an ontological point of view. The nature of modalities is indeed at the core of metaphysics and philosophical theology. Ludger Honnefelder, Joël Biard, and Fabrizio Mondori all show the influence of Duns Scotus on the setting of modern metaphysics. The importance of theological matters in the development of philosophical thought has been acknowledged for a long time. Thus Chris Schabel ("Divine Foreknowledge and Human Freedom: Auriol, Pomponazzi, and Luther on 'Scholastic Subtleties'") sketches the story of the controversy over God's foreknowledge and future contingents from its setting in the early fourteenth century to Lutheran Reformation. He stresses the underestimated influence of Peter Auriol in this continuing debate. Still, revealed theology too exercised influence on the philosophy of logic. Trinity constitutes an until now little studied case, which is the subject matter of Simo Knuuttila's contribution ("The Question of the Validity of Logic in Late Medieval Thought"). He partly rehearses some of his well-known theses about the source of logical truths and modalities and analyses the constructivist aspects of Descartes's position, in so far as the laws of logic are said to depend on God's will. But the most original part of the study bears on the effects of Trinitarian constraints within the field of logic, especially in syllogistics. Medieval thinkers had to cope with syllogisms like: "The divine essence is the father; the divine essence is the Son; therefore the Son is the Father." In order to avoid the absurdity of the conclusion, many answers were elaborated: Robert Holcot removed the Trinity from the domain of validity of syllogistics, thereby relativizing it. Luther's claim that the principles of theology contradict those of logic looks like a radical version of this position. Adam Wodeham maintained contrariwise the universality of syllogistics: he held that the premisses are not syllogistic if they are interpreted as true (130). His account is based on the identity theory of predication and on the distinction between intensional and extensional identity, which both date back to Abelard.In the period covered by the volume, early modern scholastic, chiefly the Jesuit scholastic, holds a central place. Two articles insist on its originality and intrinsic value. Jeffrey Coombs ("The Ontological Source of Logical Possibility in Catholic Second Scholasticism") [End Page 208] analyzes the various metaphysics of modalities. He claims that three theories of the source of logical modalities were entertained during the early seventeenth century, which he labels respectively "transcendentalism," "modal voluntarism," and "divine conceptualism." All of these positions can be traced back to medieval theories; however, they received an extensive treatment in late scholastic thought. Coombs is especially illuminating when he emphasizes the importance of the grounding metaphysical structure: essences and their systematic relations through "Porphyrian trees." This generated two different accounts of the ontological status of essences: according to essentialist theories, complete Porphyrian trees are the basis of necessity and possibility, while according to a "string theories," only the logical connections between the components of the essential structure are available eternally (196).Yet the most striking novelty of the time lies in the systematization of a statistical interpretation of modalities through the "moral modalities," originating in post-Tridentine Catholic theology. In contrast to Hacking's thesis (see The Taming of Chance [Cambridge, 1990]), Sven Knebel ("The Renaissance of Statistical Modalities in Early Modern Scholasticism") contends that the concept of aleatory probability was first developed within this context. That an event-type Q is morally necessary means that Q is always the case, and that not-Q actually is never the case (236... (shrink)

In his logical treatises, John Mair develops a method and a set of rules for the verification of modal propositions, which is in the spirit of his predecessors Ockham and Buridan, but ultimately goes beyond them. He calls this method positio de inesse. It is also by this method that the truth conditions for divided modal propositions are set out. There is a standard interpretation of it as a form of reductionist method, and scholars have been tempted to think that (...) it was motivated by an implicit rejection of de re modal properties shared by Mair and other sixteenth- century nominalists. After presenting the background to Mair’s writings on the semantics of modal propositions, in this paper we revisit Mair's version of the method of positio de inesse. We argue that it is based on some basic semantic rules and contend that this procedure analyzes divided modal propositions into singular de re sentences referring to possible objects. Consequently, we conclude that this method does not reflect a reductionist approach to modal discourse. We instead provide an alternative interpretation. (shrink)

The myth of Sisyphus symbolizes the archetypal process of becoming without the consolation of absolute achievement. It is a poignant reflection of idealized aspirations and actual limitations of the human condition. It is also a prominent framing text for the interpretation of classical and patristic literature, medieval allegorical and alchemical interpretations of mythology, and humanist philosophical, educational, and utopian ideologies, and erotic and heroic theories of human perfectibility. Sisyphus defines the modalities of human transcendence in classical and (...) Christian terms; he is the personification of the unrequited lover; and he is the embodiment of the aspirant renaissance hero. (shrink)

Modality: A History provides readers a sweeping study of the history of philosophical work on modal concepts. Everyday discourse is saturated with appeals to what might be the case or to what must be true or to what cannot happen. Possibility, necessity, and impossibility are modal terms, and philosophers have long wondered how to best understand them. This volume traces the history of some of the most prominent and important contributions to our understanding of possibility and necessity over the past (...) two and half millennia of western philosophy, from ancient Greek philosophers through current debates in the 21st century. Over the course of nine chapters from prominent scholars, this volume traces a history of modal theorizing that begins with extended discussions of Aristotle and the Stoics. Several chapters discuss insights and disagreements among Latin, Arabic, and Jewish medieval scholastics, such as Al-Ghazâlî, Scotus, and Crescas. Three chapters center on early modern philosophers, whose modal views were deeply shaped by this conceptual inheritance but also departed from it in significant ways: Descartes, Malebranche, Locke, Spinoza, Leibniz, and Hume. Kant and Hegel's modal contributions are presented in their own chapter, and another chapter traces the legacy of Kant's account on early-to-mid 20th century modal views, including Husserl, Heidegger, Russell, and Quine. The revival of modal metaphysics in the more recent work of Kripke, Marcus, and Lewis has led to a new flourishing of modal theories, including in recent debates among neo-Aristotelians, as the final chapter illustrates. Although modal concepts are interesting and important on their own, theories of modality often intersect with other significant philosophical topics, such as time, freedom, and God. Modal concepts also extend beyond metaphysics. To illustrate the role of modality in other domains, several small-scale studies, or Reflections, are dispersed among these main chapters on modality in cosmology, religion, music, literature, and logic. Readers will learn how a seemingly timeless and changeless cluster of modal concepts have undergone significant revisions and enjoy a rich developmental history. (shrink)

This book presents the first study of the development of the theory of modal syllogistic in the Middle Ages.

The early thirteenth century tract Ars Meliduna deals with the issue whether categorical propositions entail, or are entailed by, ‘continuing’ propositions, i.e. by implications. From the perspective of modern logic, with implication interpreted as a material, truth-functional connective, the first question has to be answered in the affirmative because, e.g. β entails (α ⊃ β). But conversely (α ⊃ β) ‘normally’ doesn’t entail the truth (or the falsity) of any of the components α, β; hence the second question should be (...) answered in the negative. These results cannot, however, be directly transferred to medieval logic because implication was there usually interpreted as a strict implication. Yet, within the framework of modal logic, one obtains parallel results. In particular, whenever β is necessary, then (α → β) must be true. Furthermore, if (α → β) is itself necessary, then it is entailed by α. Thus, in particular, ‘Socrates is a man’ entails the analytically true implication ‘If Socrates is a man, Socrates is an animal’, and the same premiss also entails the tautological consequent ‘If Socrates is white, Socrates is white’. (shrink)

In recent years modal syllogistic provided by 14th century logician John Buridan has attracted increasing attention of historians of medieval logic. The widespread use of quantified modal logic with the apparatus of possible worlds semantics in current analytic philosophy has encouraged the investigation of the relation of Buridan’s theory of modality with the modern developments of symbolic modal logic. We focus on the semantics of and the inferential relations among the propositions that underlie Buridan’s theory of modal syllogism. First, (...) we review all inferences between propositions of necessity, possibility, contingency, and non-contingency, with or without quod est locution, that are valid in Buridan’s semantics, and offer a comprehensive diagrammatic representation that includes them all. We then ask the question if there is a way to model those results in first order modal logic. Three ways of formalizing Buridan’s propositions in quantified modal logic are considered. Comparison of inferences between the quantified formulas and Buridan’s propositions reveals that, when supplied with a suitable formalization, Buridan’s semantics of categorical statements and immediate inferences among them can be fully captured by the quantified modal system T. (shrink)

This book considers different forms of voluntarism developed from the 13th to 18th centuries. By crossing the conventional dividing line between the medieval and early modern periods, the volume draws important new insights on the historical development of voluntarism. Voluntarism places a special emphasis on the will when it comes to the analysis and explanation of fundamental philosophical questions and problems. Since the Middle Ages, voluntarist considerations and views played an important role in the development of different theories (...) of action, ethics, metaethics, and metaphysics. The chapters in this volume are grouped according to three distinct kinds of voluntarism: psychological, ethical, and theological voluntarism. They address topics such as the threat of irrationality as the standard objection to voluntarism, incontinent actions and their explanation, the nature of the will as rational appetite, the relationship between intellect and will, the implications of conceptions of the will for political freedom, and the relations between divine freedom and the modal status of eternal truths. The chapters not only consider towering figures of the Middle Ages--Thomas Aquinas, Henry of Gent, William of Ockham, Francisco de Vitoria--and early modern period--René Descartes, Thomas Hobbes, Gottfried Wilhelm Leibniz, Samuel Pufendorf--but also engage with less well-known figures such as Peter John Olivi, John of Pouilly, Catharine Trotter Cockburn, and Christian August Crusius. Varieties of Voluntarism in Medieval and Early Modern Philosophy will appeal to scholars and advanced students working in medieval philosophy, early modern philosophy, the history of ethics, and philosophy of religion. (shrink)

The idea of ‘modal fields’ is inspired by regional and pluralistic ontologies, which were sketched and developed by Hegel, Husserl and especially Nicolai Hartmann. It suggests that the world is structured by spheres which are not reducible to each other, and that modal fields denote the scope of real possibilities inside the spheres. It is, for example, possible to distinguish between physical, biological, ecological, economic and technological possibilities/modal fields. It is also possible to define, for the purpose of scientific research, (...) very specific modal fields. For example, we can ask “What are the physiological or social possibilities of ants?”, or “What are the social and psychological possibilities of fundamental religious sects?” It is possible to apply this ontological theory to philosophy of science in order to clarify the scope and limits of causal explanations and hermeneutic understanding especially in human and environmental sciences. In general, this ontological theory serves as a fruitful basis for the kind of scientific thinking which is open to counterfactuals and possibilities and which considers deterministic causal thinking too restricted for human and environmental sciences. On the other hand, this theory avoids the individualistic and anthropocentric presuppositions of hermeneutical understanding, connecting it to the real subjective and objective possibilities in a certain historical situation. (shrink)

the theory of modal groups is an abstract theory that may be used to show formal similarities between various formulations of epistemic logics (eg Hintikka, Chisholm, and von Wright) and formal systems in other domains.

Proof Theory of Modal Logic is devoted to a thorough study of proof systems for modal logics, that is, logics of necessity, possibility, knowledge, belief, time, computations etc. It contains many new technical results and presentations of novel proof procedures. The volume is of immense importance for the interdisciplinary fields of logic, knowledge representation, and automated deduction.

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)

Propositions are items that play certain theoretical roles: (among other things) they serve as objects of belief, fundamental bearers of truth-value, and the semantic contents of sentences. In this paper, I examine the key role Ockham played in the development of later medieval debates about propositions. Unlike contemporary philosophers, who typically assume that propositions are abstract entities of some sort, Ockham holds a nominalist view of propositions according to which token entities—namely, token mental representations—play the proposition role. While Ockham's (...) view generates a great deal of controversy and discussion I argue that it isn't his nominalism about propositions per se that proves objectionable. Indeed, insofar as few medieval philosophers countenance abstract objects, the view that token mental representations function as fundamental bearers of truth and as the semantic content of sentences is fairly standard. What does prove controversial, I claim, is Ockham's contention that token mental states—what he refers to as ‘mental sentences’—serve as objects for propositional attitudes. My discussion in the paper explores both (i) the reasons why Ockham’s attempt to treat mental representations as objects for belief and knowledge proved controversial and (ii) what alternative positions emerged in the subsequent debate about propositional attitudes. -/- . (shrink)

From the 12 th century onwards, medieval canon lawyers and, from the early 14 th century, theologians and philosophers began to use ius to mean a right, and developed a theory of natural rights, the predecessor of modern theories of human rights. The main applications of this theory were in respect of property and government.

Many theories assimilate the idioms of modality to those of quantification; they hold that so-and-so is possible iff there is a "world" at which it is true that so-and-so. "Modal realism" identifies worlds with certain concrete particulars, and truth at a world with what is true of it. Rival "ersatz" theories identify worlds with certain abstract entities and identify what is true at them with what they represent. ;David Lewis argues that pre-theoretic modal intuitions are best explained by (...) modal realism. I try to make a case for ersatzism. ;First, I argue that modal realism is flawed on the grounds that it entails the impossibility of certain intuitively possible spatiotemporal structures; it fails to explain fully even those intuitions with which it is compatible; and it renders the origin of modal knowledge mysterious. ;Next, I argue that objections to ersatzism are not conclusive. ;Lewis objects that even a generic version of ersatzism requires an unnameable and maybe unintelligible primitive relation. I suggest that the problems with naming are perfectly general; they have nothing to do with metaphysical theories of modality in particular. And I suggest a solution taken from Lewis himself. I also argue that any purported unintelligibility is due to illegitimately assimilating the relation to spatiotemporal relations. ;Finally, I consider some difficulties with a version of ersatzism that aims to reduce modality to impure set-theory. One concerns the accommodation of intuitions about properties that are not, but might have been, instantiated. Another concerns accommodation of intuitions about relations of exclusion and entailment among properties. I suggest that these difficulties are due to faulty assumptions about the nature of properties rather than any fundamental flaws in this ersatz approach. So I propose an account of properties that when incorporated into ersatzism circumvents these difficulties and allows it to claim the advantages of modal realism without its drawbacks. Unlike traditional accounts, this takes the essence of a property to consist in its role in imposing a certain classificational structure on the particulars that instantiate it, rather than in any unique and irreducible "quiddity". (shrink)

The purpose of this entry is to provide a systematic introduction to medieval views about the nature and ontological status of relations. Given the current state of our knowledge of medieval philosophy, especially with regard to relations, it is not possible to discuss all the nuances of even the best known medieval philosophers' views. In what follows, therefore, we shall restrict our aim to identifying and describing (a) the main types of position that were developed during the (...) Middle Ages, and (b) the most important considerations that shaped their development. We shall have occasion along the way, however, to examine in detail certain aspects of the views of important representatives of all the main medieval positions, including Peter Abelard (1079 1142), Gilbert of Poitiers (1085 1154), Albert the Great, (1200 1280), Thomas Aquinas (1225 1274), John Duns Scotus (1265 1308), Henry Harclay (1270 1317), Peter Auriol (1280 1322), and William Ockham (1285 1347). (shrink)

The term ‘aesthetics’ did not become prominent until the eighteenth century in Germany; however, this fact does not prevent principles of aesthetics from being present in the Middles Ages. Developments in the Middles Ages paved the way for the future development of aesthetics as a separate discipline. Building on notions from antiquity (most notably Plato and Aristotle) through Plotinus, the medieval thinkers extended previous concepts in new ways, making original contributions to the development of art and theories of (...) beauty. (shrink)

Lloyd P. Gerson - Ancient and Medieval Theories of Intentionality - Journal of the History of Philosophy 40:4 Journal of the History of Philosophy 40.4 539-540 Book Review Ancient and Medieval Theories of Intentionality Dominik Perler, editor. Ancient and Medieval Theories of Intentionality. Leiden: Brill, 2001. Pp. x + 347. Cloth $107.00. This collection of fifteen essays originated in a conference on ancient and medieval theories of intentionality at Basel in 1999. Part (...) I: Ancient Theories contains the following papers: Victor Caston, "Connecting Traditions: Augustine and the Greeks on Intentionality"; Richard Sorabji, "Aristotle on Sensory Processes and Intentionality. A Reply to Myles Burnyeat"; Christoff Rapp, "Intentionalität und phantasia bei Aristoteles"; Hermann Weidemann, "War Aristoteles ein Repräsentationalist?"; Richard Sorabji, "Why the.. (shrink)

In a career extending over almost six decades, Nicholas Rescher has conducted researches in almost every principal area of philosophy, historical and systematic alike. In this extraordinary volume, two dozen scholars join in offering penetrating discussions of various facets of Rescher s investigations. The result is an instructively critical panorama of the many-faceted contributions of this important American philosopher. Born in Germany in 1928, Nicholas Rescher came to the U.S. at the age of nine. He is University Professor of Philosophy (...) at the University of Pittsburgh where he has also served as Chairman of the Philosophy Department and as director (and currently chairman) of the Center for Philosophy of Science. In a productive research career extending over six decades, he has established himself as a systematic philosopher of the old style. His work represents a many-sided approach to fundamental philosophical issues that weaves together threads of thought from continental idealism and American pragmatism. And apart from this larger program Rescher has made various specific contributions to logic (the conception autodescriptive systems of many-sided logic), the history of logic (the medieval Arabic theory of modal syllogistic), to the theory of knowledge (epistemetrics as a quantitative approach in theoretical epistemology), and to the philosophy of science (the theory of a logarithmic retardation of scientific progress). Rescher has also worked in the area of futuristics, and along with Olaf Helmer and Norman Dalkey is co-inaugurator of the so-called Delphi method of forecasting. Ten books about Rescher s philosophy have been published in four languages. Rescher earned his doctorate at Princeton in 1951 while still at the age of twenty-two a record for Princeton s Department of Philosophy. He has served as a President of the American Philosophical Association, of the American Catholic Philosophy Association, of the American G. W. Leibniz Society, of the C. S. Peirce Society, and of the American Metaphysical Society. He was the founder of the American Philosophical Quarterly. An honorary member of Corpus Christi College, Oxford, he has been elected to membership in the European Academy of Arts and Sciences (Academia Europaea), the Royal Society of Canada, the Institut International de Philosophie, and several other learned academies. Having held visiting lectureships at Oxford, Constance, Salamanca, Munich, and Marburg, he has been awarded fellowships by the Ford, Guggenheim, and National Science Foundations. Author of some hundred books ranging over many areas of philosophy, over a dozen of them translated from English into other languages, he is the recipient of eight honorary degrees from universities on three continents. He was awarded the Alexander von Humboldt Prize for Humanistic Scholarship in 1984, the Belgian Prix Mercier in 2005, and the Aquinas Medal of the American Catholic Philosophical Association in 2007.". (shrink)

This paper presents a new theory of modal reasoning, i.e. reasoning about what may or may not be the case, and what must or must not be the case. It postulates that individuals construct models of the premises in which they make explicit only what is true. A conclusion is possible if it holds in at least one model, whereas it is necessary if it holds in all the models. The theory makes three predictions, which are corroborated experimentally. First, conclusions (...) correspond to the true, but not the false, components of possibilities. Second, there is a key interaction: it is easier to infer that a situation is possible as opposed to impossible, whereas it is easier to infer that a situation is not necessary as opposed to necessary. Third, individuals make systematic errors of omission and of commission. We contrast the theory with theories based on formal rules. (shrink)

This work presents a causal conception of metaphysical modality in which a state of affairs is metaphysically possible if and only if it can be caused (in the past, the present or the future) by current entities. The conception is contrasted with what is called the "combinatorial" conception of modality, in which everything can coexist with anything else. This work explains how the notion of 'causality' should be construed in the causal theory, what difference exists between modalities thus defined (...) from nomological modality, how accessibility relations between possible worlds should be interpreted, and what is the relation between the causal conception and the necessity of origin. (shrink)

Logic begins but does not end with the study of truth and falsity. Within truth there are the modes of truth, ways of being true: necessary truth and contingent truth. When a proposition is true, we may ask whether it could have been false. If so, then it is contingently true. If not, then it is necessarily true; it must be true; it could not have been false. Falsity has modes as well: a false proposition that could not have been (...) true is impossible or necessarily false; one that could have been true is merely contingently false. The proposition that some humans are over seven feet tall is contingently true; the proposition that all humans over seven feet tall are over six feet tall is necessarily true; the proposition that some humans are over seven feet tall and under six feet tall is impossible, and the proposition that some humans are over nine feet tall is contingently false. Of these four modes of truth, let us focus on necessity, plus a fifth: possibility. A proposition is possible if it is or could have been true; hence propositions that are either necessarily true, contingently true, or contingently false are possible. Notions that are similar to the modes of truth in being concerned with what might have been are called modal. Dispositions are modal notions, for example the disposition of fragility. Relatedly, there are counterfactual conditionals, for example “if this glass were dropped, it would break.” And the notion of supervenience is modal.1 But let us focus here on necessity and possibility. Modal words are notoriously ambiguous (or at least context-sensitive2). I may reply to an invitation to give a talk in England by saying “I can’t come; I have to give a talk in California the day before”. This use of “can’t” is perfectly appropriate. But it would be equally appropriate for me to say that I could cancel my talk in California (although that would be rude) and give the talk in England instead. What I cannot do is give both talks.. (shrink)

This paper is dedicated to the formulation of a restricted theory of ontic modality (for example, I do not address questions that arise when modal operators interact with quantifiers, although some of the theoretical developments presented here certainly suggest such questions). As will be seen, notwithstanding its restrictions, the theory has a pleasing richness to it, as well as formal rigor and intuitive satisfactoriness. It also offers an unusual perspective on modality.

In this anthology, most of the important cosmological hypotheses within the Western tradition, from the Enuma Elish creation-myth of Babylon to the continuous “creation” hypothesis of Bondi and Gold, are gathered together. Most of them are presented in their originator’s own words. The work falls into three parts. The first deals rather summarily with the Greek period. Despite the research of the past few decades into mediaeval science, the mediaeval period is represented only by a rather dated and onesided article (...) by Dreyer. The second part covers the Copernicus-Kant period in some detail; it includes authors as diverse as Cusa and Bruno, Huygens and Herschel. The third begins with Einstein, works through the “expanding universe” theories of Lemaître and Gamow and ends with Hoyle’s “infinite” universe. The editor has added brief introductory notes and a bibliography. (shrink)

The topic of my dissertation is the treatment of the fallacies of composition and division during the scholastic period , the compounded/divided sense distinction which grew out of that treatment, and the philosophical use to which the distinction was put. For instance, a recognition of these fallacies during the twelfth and thirteenth centuries helped theologians deal with certain problems having to do with foreknowledge and human freedom. In addition, a recognition of the distinction between the compounded and divided senses of (...) propositions allowed medieval logicians after the first quarter of the fourteenth century to get clearer about what might broadly be described as the logic of propositional attitudes. ;In Chapter 1, I briefly summarize and compare theories of composition and division from Peter Abelard to Paul of Pergula . And in Chapters 2 and 3, I examine the treatments of composition and division presented by Lambert of Auxerra , Roger Bacon , and William Ockham . In these treatments, composition and division are viewed in terms of ambiguity. ;By the second quarter of the fourteenth century, one sees the discussion of composition and division move from a concern with ambiguous expressions to a concern with arguments comprised of unambiguous sentences having either the compounded sense or the divided sense in virtue of the sentence's word-order. "Infinitely fast does Socrates run; therefore, Socrates runs infinitely fast" is, according to William Heytesbury , invalid: the premise has the divided sense, and is possibly true; the conclusion has the compounded sense, and is impossible. With Heytesbury there is an increasing emphasis on the compounded/divided sense distinction in connection with verbs signifying mental acts or acts of will: 'know,' 'believe,' 'desire,' 'understand,' etc. In Chapter 4 I explain why these shifts may have occurred in the medieval treatment of composition and division. And in Chapter 5, I consider the effect of Heytesbury's treatment of composition and division on logicians and commentators who come after him. I focus in particular on the work of four fifteenth- through sixteenth-century Italian logicians and their views on epistemic logic. (shrink)