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Wyclif and the Realist Tradition in 14th-Century Logic



  Time: 16 May, 2015 - 17 May, 2015
  Location: Hebdomadar's Room, St Salvator's Quad
Historians of logic have known for decades that the 14th century was a tremendously productive period in the Latin West. As far as the relationship between logic and metaphysics is concerned, however, research has tended to focus on the nominalist tradition associated with Ockham and Buridan. The aim of this workshop is to redress the balance a little by focussing instead on the realist tradition that spans the century. We have singled out for special mention the influential figure of John Wyclif, whose Logic is currently being re-edited here at St Andrews, but the workshop will also consider other figures in the tradition stretching from Walter Burley to Paul of Venice. Abstracts can be found below.


Registration is free of charge, and includes tea and coffee between the talks. To register, please email the organizers Mark Thakkar ( and Stephen Read.

Saturday 16 May: from Walter Burley to Richard Brinkley

09:30 Tea/Coffee
10:00 Nate Bulthuis (Cornell) 'Supposition and the Semantics of Mental Sentences in Walter Burley'
11:00 Tea/Coffee
11:30 Martin Lenz (Groningen) 'Burley and Chatton on States of Affairs'
12:30 Lunch
14:00 Heresy Tour of St Andrews (Bess Rhodes)
15:00 Tea/Coffee
15:30 Josh Blander (King's College, NYC) 'It All Depends… Well, Almost All: The Nature of Essential Dependence in Walter Chatton and William Ockham'
16:30 Tea/Coffee
17:00 Laurent Cesalli (Geneva) 'Richard Brinkley's Semantics of Terms'
18:00 Finish
19:00 Workshop Dinner

Sunday 17 May: from John Wyclif to Paul of Venice

09:30 Tea/Coffee
10:00 Mark Thakkar (St Andrews) 'Wyclif's Logic: First Fruits of the New Edition'
11:00 Tea/Coffee
11:30 Alessandro Conti (L'Aquila) 'The Nature and Kinds of Real Predication in Wyclif and his Followers'
12:30 Lunch
14:00 Miroslav Hanke (Czech Academy of Sciences) 'Paul of Venice and Realist Developments of the Swyneshedian Treatment of Paradoxes'
15:00 Tea/Coffee
15:30 Sara Uckelman (Durham) 'Paul of Venice on Objects and Conditions of Knowledge'
16:30 Finish


We gratefully acknowledge financial support from the British Logic Colloquium, the Leverhulme Trust, the Scots Philosophical Association and the University of St Andrews.

'Supposition and the Semantics of Mental Sentences in Walter Burley' (Nate Bulthuis)

Throughout his career, Walter Burley defends an account of what Elizabeth Karger (1996) calls mental sentences: propositions formed by the mind from things outside of it (res extra animam). In his 1337 commentary on the old logic, Burley claims that the terms of mental sentences—that is, things—can supposit: either for themselves or (if they are universals) for the individuals which possess them. Karger argues that the same view is likely to be found in Burley’s earlier logical commentaries as well. She first notes Burley’s claim in a 1301 work that the terms of mental sentences have distribution, and then suggests that, since supposition is a semantic property of a type similar to distribution, Burley likely intends in that work for the terms of mental sentences to have supposition as well.

However, unlike distribution, Burley does not need to employ the notion of supposition in earlier analyses of the semantics of mental sentences. Instead, Burley could—and, I argue, does—articulate that semantics in terms of a moderate realist account of identity to which he was then committed. It is only when Burley’s account of identity undergoes significant revision (likely on account of certain criticisms of moderate realism developed by William Ockham) that supposition becomes essential to his analysis of the semantics of mental sentences. In other words, it is Burley’s transition from moderate to “exaggerated” realism that necessitates the use of supposition in his 1337 analysis of the semantics of mental sentences. Burley’s analysis of the semantics of mental sentences is, then, directly affected by the form of realism he defends, a fact which has so far gone unnoticed in the scholarship.

'Burley and Chatton on States of Affairs' (Martin Lenz)

In this paper, I will look at some arguments of Walter Burley and Walter Chatton, who defended the position that the significates of propositions and objects of belief are things. While realism about propositional significates and especially Burley’s assumption of real entities that are structured like propositions (propositiones in re) is often compared to analogous claims about states of affairs or (Russellian) propositions in the early 20th century, I would like to highlight a different issue. Can things or states of affairs be the direct objects of mental activity? In other words: can things be the objects of belief without any cognitive intermediaries? Both Chatton and Burley defend a form of this direct realism and thus seem to endorse the view that the mind can operate with the things themselves, rather than requiring intermediaries.

As I see it, the debates Burley and Chatton engaged in take their cue from an even more radical view on the problem at issue: namely the view that we cannot take for granted that a proposition is a linguistic or mental entity. Thus, it is called into question whether there is a clear separation of language and thought, on the one hand, and the real world on the other. In the light of the traditional separation of language, mind and world, this solution sounds very odd indeed. But as I see it, this view has systematic merits that yet have to be exposed.

'It All Depends… Well, Almost All: The Nature of Essential Dependence in Walter Chatton and William Ockham' (Josh Blander)

William Ockham and Walter Chatton were frequent philosophical sparring partners during the fourteenth century. However, while engaged with one another in a dispute about (at least one version of) Ockham’s fictum theory, both affirmed the following metaphysical principle:

When some thing really distinct from other things can in the course of nature exist without any one of them taken separately, and it does not depend essentially on any of them, then it can exist without all of them taken all together.
Commentators on this passage, such as Paul Spade, have suggested that the principle seems obviously fallacious. The criticism seems to be that Chatton and Ockham have committed some sort of quantifier shift fallacy. More specifically, it seems like they are endorsing the possibility that (b) can follow from (a):
(a) It is not the case that there is an x such that U requires it;
(b) It is not the case that U requires that there is an x.
If this reconstruction is correct, then the principle seems to permit unlicensed inferences.

In my paper, I argue that both Chatton and Ockham are committed to this principle – so we cannot extricate them from the problem by suggesting that they were using it merely arguendo. More importantly, I claim that the principle does not commit either of them to a fallacy. In order to do so, I examine what Chatton and Ockham mean by essential dependence, a topic that both mention, but which is often overlooked by commentators discussing the passage. Finally, I explain the connection between essential dependence and their accounts of divine power and logical possibility in order to show the plausibility of the principle.

'Richard Brinkley's Semantics of Terms' (Laurent Cesalli)

The Franciscan Richard Brinkley is the author of a Summa logicae (c. 1350), in which he defends an anti-Ockhamist though moderate realism. Contrary to the other six parts of the Summa, which have been edited (or at least studied), the first one—De terminis, still unedited—has not been investigated yet. I my paper, I’ll present Brinkley’s main claims, and compare them with the opinions of some other medieval logicians, from the time of Roger Bacon to that of John Wyclif. The following points will be considered: (1) the nature of signification (which entities and relations are required in order to give an appropriate description of what it means for a vocal sound to have signification?); (2) the role of mental entities—species, conceptus, intentiones—in the semantics of terms (does Brinkley explain signification in terms of mental mediation, or in terms of subordination, or does he combine the two approaches?); (3) the nature of the items signified by the different types of terms (singular, general, categorematic, syncategorematic, denominative); (4) the claim that intentiones—i.e. a kind of terms of mental language—divide not only into first and second intentiones, but also into a third, intermediary type of intentiones. It will turn out that Brinkley defends a multi-relational conception of signification akin to the one expounded nearly a century earlier by Roger Bacon in his De signis. Furthermore, Brinkley, like Ockham, adopts the principle of semantic subordination of extra-mental language to mental language; but unlike his nominalist anti-model, he stresses the necessity of the species as a cognitive mediating device (with the result that species are the key elements of Brinkley’s account of the impositio nominum). Finally, being a realist with respect to universals, Brinkley defends the idea that common terms signify things (res) that are sharable by themselves (de se communicabiles) without accepting that universals exist either separately, or as integral parts of particulars (and in that respect, his realism is akin to that of John Duns Scotus).

'Wyclif's Logic: First Fruits of the New Edition' (Mark Thakkar)

Most of Wyclif’s works were printed for the first and only time in the late 19th and early 20th century under the auspices of the Wyclif Society. These editions are notoriously variable in quality, but worst of all are the three volumes that appeared from 1893 to 1899 under the collective title Tractatus de Logica. This is especially unfortunate because the two works printed in these volumes, known to modern scholars as De logica and Logice continuatio, are considered to be fundamental for an understanding of Wyclif’s philosophy. I have therefore started to prepare a new critical edition from the nine known manuscripts, including a tantalizing fragment that was recovered from a book binding ten years ago.

I will begin by describing the two works in question and explaining the need for a new edition. (This will essentially be a recap of a paper that I gave here in May 2014 under the title ‘Towards a New Edition of Wyclif's Logic’.) I will then present the first fruits of my work, concentrating on passages that have a bearing on Wyclif’s place in the realist tradition. I will also provide a first draft of my edition of the De logica for those who would like to see it.

'The Nature and Kinds of Real Predication in Wyclif and his Followers' (Alessandro Conti)

As is well known, Wyclif many times in his works distinguishes different kinds of predication he conceives as a real relation holding between metaphysical entities. In the Logicae continuatio (tr. 3, ch. 2, 40-42), Wyclif distinguished four different kinds of predication, that he conceived as a real relation which holds between metaphysical entities: (i) predication by essence (secundum essentiam); (ii) formal predication (per inherenciam forme); (iii) causal predication (secundum causam); and (iv) habitudinal predication (secundum habitudinem). In the second and third chapters of the Purgans errores circa universalia in communi (composed between 1366 and 1368) Wyclif lists the following three main types of predication: formal predication, predication by essence, and causal predication; on the contrary, in the Tractatus de universalibus (ch. 1, 35-36) causal predication is replaced by habitudinal predication - a kind of predication that Wyclif had already recognized in the Purgans errores circa universalia, but whose position within the main division of the types of predication was not clear, as it seems to be a sub-type of the formal predication, even though it does not satisfy the criterion of the direct inherence of the form signified by the predicate in the essence signified by the subject. Formal predication, predication by essence, and habitudinal predication are defined almost in the same way in the Purgans errores circa universalia and in the Tractatus de universalibus, but in the Tractatus de universalibus formal predication, predication by essence, and habitudinal predication are described as three non-mutually exclusive ways of predicating, each more general than the preceding one (or ones).

Modifying to some extent Wyclif’s main ideas, his followers introduced a new basic type of predication, based on a partial identity between the entities for which the subject and predicate stand, called predication by essence (praedicatio secundum essentiam), and redefined the traditional categories of essential and accidental predication in terms of partial identity.

In particular, Alyngton, and some years later Sharpe, Milverley, and Tarteys, divided predication into formal predication and predication by essence (secundum essentiam), that Alyngton calls also “remote inherence” (inhaerentia remota). Predication secundum essentiam shows a partial identity between subject and predicate, which share some, but not all, metaphysical component parts, and does not require that the form connoted by the predicate-term is directly present in the essence denotated by the subject-term. Formal predication, on the contrary, requires such a direct presence.

Unlike Wyclif, who applied predication by essence to second intentions only, these later philosophers thought that it held also when applied to first intentions. So they affirmed that it was possible to predicate of the universal-man (homo in communi) the property of being white, if at least one of its individuals was white. However they made sure to use as a predicate-term a substantival adjective in its neuter form, because only in this way it can appear that the form connoted by the predicate-term is not directly present in the subject, but it is indirectly attributed to it, through its individuals. Therefore they acknowledged the proposition “homo in communi est album” as a true one, if at least one of the existing men was white.

By contrast, Penbygull and Whelpdale, who almost certainly belong to the same generation as Sharpe, were closer to Wyclif’s teaching as manifested in the Purgans errores circa universalia in communi, since they divided predication into formal (praedicatio formalis), by essence (secundum essentiam), and causal (secundum causam). Predication by essence shows a partial identity between subject and predicate, which share some, but not all, metaphysical component parts, and does not require that the form connoted by the predicate-term is directly present in the essence denoted by the subject-term. Formal predication, on the contrary, requires such a direct presence. And there is a causal predication when the entity signified by the predicate-term is not present in any way in the entity signified by the subject-term, but the real subject has been caused by the real predicate (“dies est latio solis super terram” is an example of this kind of predication).

Both these interpretative schemes of the nature and kinds of predication (that worked out by Alyngton and that elaborated by Penbygull and Whelpdale) are ultimately grounded on a notion of identity that is necessarily different from the common one - according to which two things a and b are identical if and only if for all P, it is the case that P is predicated of a if and only if it is predicated of b.

'Paul of Venice and Realist Developments of the Swyneshedian Treatment of Paradoxes' (Miroslav Hanke)

As part of his treatment of semantic paradoxes, Roger Swyneshed drew a distinction between two factors of truth-making, the compositional factors (or: what the sentence signifies) and the contextual factors (or: what the linguistic context of the sentence in question is). The resulting definition of truth states two truth-conditions: correspondence with reality (or: “significare sicut est”) and the absence of paradox (or: “non se falsificare”). Both parts of this definition underwent further development, part of which is Paul of Venice’s Logica magna. As opposed to Swyneshed’s ontologically neutral formulation in terms of the relation of signification (significare), one of these developments redefined compositional meaning in terms of objective propositional meaning (“significatum adaequatum” or even “complexe significabile”). This reification of propositional meaning raises two kinds of issues. First, the issue of the ontological status of propositional meaning. Second, the logical issues of the semantic and logical implications of introducing propositional meanings as a specific type of truth-bearers, including the redefinition of logico-semantic relations, the question of paradoxical propositional meanings etc. My paper will attempt to focus on issues of the second type, i.e., on the new opportunities as well as specific logico-semantic challenges raised by this realist ontological decision in the context of the Swyneshedian semantic tradition.

'Paul of Venice on Objects and Conditions of Knowledge' (Sara Uckelman)

Paul of Venice's place in the history of logic affords him unparalleled access to two of the most productive centuries in the development of logic. As such, he is uniquely positioned to comment both within and on that tradition, a position he takes advantage of in the Logica Magna, a tour de force of the state of the art of logic at the beginning of the 15th C. Learning and teaching in Italy, he was firmly within the "English" tradition in logic (cf. Maieru, English Logic in Italy in the 14th and 15th Centuries), but it was the English realist tradition developed in large part by Wyclif rather than the nominalist tradition of Ockham and Buridan.

In this paper we focus on Paul's comments on knowledge and reasoning about knowledge. It is divided into two parts: In the first, we discuss the objects of knowledge: What is it that we can know? We outline Paul's views as well as contrast them with views of his contemporaries and some relevant modern views. In the second, we look at what he says about the conditions of knowledge: When do we have it? Are there different grades? How does this constraint our ability to reason to and from knowledge claims? By considering these questions we hope to point out both what is unique and interesting about Paul's views, but also how he develops and extends Wyclif's realism.

Leverhulme Trust
Scots Philosophical Association