Three problems involving future contingents

There is more than one problem of future contingents. There is first the problem raised by Aristotle – that of reconciling the principle of bivalence (the principle that for any sentence P either P is true or not-P is true) with the view that some claims about the future are contingent, are such that neither the claim nor its denial is necessarily true. Medieval discussions of this problem often rely on our intuitions that the past and the present are ‘fixed’ in some way in which the future is not, and so these discussions often illuminate medieval views on tense and modality.

A second problem has to do with the possibility of foreknowledge. Can one hold both that some future event is contingent and that it is foreknown?

A third problem is specifically theological. Can complete knowledge of the future by an immutable, infallible, impassible God be reconciled with the contingency of some aspects of the future?

These are distinct problems. Theories which solve the problem of contingent truth may fail to account for foreknowledge, and theories which account for both future contingent truth and foreknowledge may yet fail to explain how contingent future events, e.g. sins, can be known by a knower who cannot be causally acted upon.

Yet all three problems are variations on a single theme. We are inclined to think that there is an objective difference between the past and the future.

Terms and propositions

Separate treatments of the semantics of terms and the semantics of propositions are justified by the Aristotelian distinction between two levels of speech and thought (Categories 1a16, 2a4; De interpretatione 16a10): the level of names and verbs and the thoughts corresponding to them, which do not yet involve any combination (symplokē, complexio) that makes the notions of truth and falsity applicable, and the level of expressions and thoughts formed by a kind of combination that has to do with truth and falsity. Just as Aristotle had made the applicability of the notions of truth and falsity the criterion for the relevant kind of combination, the medieval semantics of complex units of speech and thought (complexa) concentrated on sentences that are used for making statements and are thus either true or false – the sort of sentences with which logic is primarily concerned. A combination of words that is used to make known something that is either true or false (oratio verum falsumve significans) was called an enuntiatio or propositio. The Latin word ‘propositio’ practically always designates a declarative sentence; accordingly, in this chapter ‘proposition’ is used in this medieval sense and never in the modern sense of that which is expressed by a declarative sentence. Most medievals were aware of a distinction between a complexio in the sense of mere predication, without any assertive (or other) force, and a complexio which is accompanied by an act of judging or asserting that it is so.

The scope of this study

This study makes no pretensions to being a comprehensive survey of medieval commentaries on the Politics; it is confined to a few of the known commentaries on Moerbeke's translation, all dated to the late thirteenth and the fourteenth centuries. Within this narrow range, it aims to discuss, firstly, how close the earliest commentaries, those of Albert the Great and of Thomas Aquinas with the Continuation by Peter of Auvergne, came to explaining Aristotle's meaning accurately and, secondly, what motives later commentators had in writing, what arguments they considered valid, and how far, if at all, their own views can be inferred from what they wrote. To make some useful comparison between the texts, I shall, after a few introductory remarks on each commentary, concentrate on what each scholar made of Aristotle's arguments for the proposition that the multitude of freemen in a state should participate in its political life (Politics III, 1281b and 1282a). Because they recognised its importance, all the commentators expanded, illustrated, or interpreted this passage in a way which brings out their individual characters and sometimes their political ideas.

William of Moerbeke's translation

The exact date at which Moerbeke finished his translation of the Politics is still uncertain, but it was probably around 1260. Moerbeke tried to render Aristotle's meaning without the slightest interpretation of his own – an aim which he believed could be best fulfilled by translating word for word, preserving the Greek word order, some Greek double negatives, and even an occasional Greek term – e.g., ‘epikeiea’ – for which there was no exact Latin equivalent.

Two senses of ‘term’

Medieval philosophers and logicians used the word ‘term’ (terminus) in several senses, two of which are especially pertinent to this discussion. Strictly speaking, a term is what is subjected to the predicate or predicated of the subject in an ordinary categorical proposition – the subject term or the predicate term, the two ends (termini) of the proposition. In this sense whole phrases may be terms, but only certain sorts of words – nouns, adjectives, and verbs – can serve by themselves as terms. Less strictly, and in the later Middle Ages more prevalently, a term is any word at all, regardless of propositional context. In this discussion ‘term’ will be used in the less strict sense unless otherwise noted.

Signification as a psychological and causal property of terms

There are two basic properties for the medieval semantics of terms: signification and supposition. Signification is a psychologico-causal property of terms – a fact responsible for many disagreements and tensions in medieval semantics. The main source for the notion of signification was Boethius' translation of De interpretatione 3, 16b 19: ‘[Verbs] spoken in isolation are names and signify something. For he who speaks [them] establishes an understanding and he who hears [them] rests’. Hence ‘to signify’ something was ‘to establish an understanding’ of it. The psychological overtones of ‘to signify’ are similar to those of the modern ‘to mean’. Nevertheless, signification is not meaning. A term signifies that of which it makes a person think, so that, unlike meaning, signification is a species of the causal relation.

Scientia demonstrativa in the Middle Ages

From the thirteenth century down to the Renaissance, philosophers attempted to forge plausible accounts of Aristotelian ‘demonstrative science’ and its basis, the ‘knowledge-producing syllogism’ (syllogismus faciens scire). The term ‘scientia demonstrativa’ is ambiguous, referring both to the knowledge a demonstrative syllogism effects in someone who understands it and to a system of syllogisms comprising propositions which satisfy the requirements for demonstration stipulated in Aristotle's Posterior Analytics. In expounding Aristotle's theory, medieval authors typically interpret and criticise it in the light of their own conceptions and doctrines; for example, their treatments of the requirements that premisses of demonstrative syllogisms be true, necessary, and certain invoke various views of truth, necessity, and certainty. So while it is true that almost all the major figures of medieval philosophy in some sense endorse what is traditionally called ‘the Aristotelian ideal of demonstrative science’, this appearance of unanimity can be misleading. The generalisation that this ideal dominated medieval thinking regarding scientific knowledge obscures or ignores the variety in philosophical accounts of its foundation and scope.

Much of our current understanding of medieval epistemology is based on doctrines concerning acquaintance with and knowledge of particular entities or states of affairs, and the subsequent formation of general concepts. Because discussions of more elaborate cognitive activities, those involving relatively complex judgements and inferences, have until recently received less attention, the full significance of theories of demonstrative science in late medieval epistemology remains to be determined.

Potentia Dei absoluta

The Condemnation of 219 articles in theology and natural philosophy by the bishop of Paris in 1277 points to a significant development in the history of medieval philosophy generally, but especially natural philosophy. Whatever may have induced bishop Stephen Tempier and his advisers to promulgate the condemnation, the most significant outcome was an emphasis on the reality and importance of God's absolute power (potentia Dei absoluta)to do whatever He pleases short of bringing about a logical contradiction. Although the doctrine of God's absolute power was hardly new in the thirteenth century, the introduction into the Latin West of Greco-Arabic physics and natural philosophy, with their independent, and often deterministic, philosophical and scientific explanatory principles, conferred on that doctrine a new and more significant status. After 1277, appeals to God's absolute power were frequently introduced into discussions of Aristotelian physics and cosmology.

The range of the Condemnation

The wide range of topics covered by the Condemnation indicates its potential impact on natural philosophy. Among the themes at which several articles were directed are God's knowability, nature, will, and power; the causation and eternality of the world; the nature and function of intelligences; the nature and operation of the heavens and the generation of terrestrial things; the necessity and contingency of events; the principles of material objects; man and the active intellect. Whether implicitly or explicitly, many of the articles asserted God's infinite and absolute creative and causative power against those who those who thought to circumscribe it by the principles of natural philosophy.

Scotus and Ockham as the focal points of the discussion

The fourteenth century is especially rich in controversies about knowledge, but our understanding of them, while improving, is still limited. The relevant texts are not widely available, and as a result the analysis that has been produced is isolated and sketchy. Consequently, while we can frame tempting hypotheses about developments in the period and their influence on subsequent thought, it is still the familiar landmarks that best serve to present the themes of the time and the orientations of recent commentary. Especially notable among those landmarks are the theories of intuitive cognition in Duns Scotus and William Ockham. Nearly all the medieval discussions of intuition that follow them are an attack on or defence of one or the other. Consequently, a presentation of the notion of intuition that focuses around Scotus and Ockham will provide a useful picture of the terrain on which subsequent battles have been fought.

The problem of the cognition of individuals

Around 1250 – the position of William of Auvergne suggests things may not have been so neat in the immediately preceding period – writers of both Aristotelian and Augustinian persuasions could maintain as a matter of course that the province of the human intellect is the immaterial, so that with respect to the physical world our cognitive experience of existent individuals comes through sensation while the intellect contributes only the universal. Orthodox belief, of course, required that God's knowledge extend, as his providence does, to individuals.

Lordship and ownership

Before the arrival in the west of Aristotle's Politics, the origin of organised society was usually discussed in terms of the institution of lordship and ownership (dominium). Dominium was seen to arise from an act of force, an act of God, human agreement or an amalgam of these, just as in fact the assumption of power often proved to be a combination of events such as usurpation, the test of utility and merit, ‘divine right’, hereditary claims and election or confirmation by the community or its clerical part.

The view that lordship arose from the forceful assumption of power and the subjection of other men had been handed down by Patristic writers. It was illustrated by the story of the Fall and of the appearance with Cain and Nimrod of sinful ambition and dominion, and it reflected too the Stoic assumption (cf. Seneca, Epistola, XIV.2 (90)) that men had enjoyed equality, freedom, and self-sufficiency in an original state of innocence which had been lost through the appearance of human wickedness. The history of the ancient Roman empire attracted much interest since it had obviously gained authority from conquest. Government, then, was the consequence of sin and it arose from the lust for power and domination. But in so far as coercive authority restrained further abuse of free will, it was a necessary and legitimate remedy of sin. After the loss of innocence many men were no longer fit to enjoy freedom and equality or to practice common ownership.

The humanists' attitude towards scholastic philosophy

There is a certain irony in the fact that it was the humanists with their enthusiasm for the literature of the ancient world who were in large part responsible for the demise of scholastic grammar. For inasmuch as humanism was a literary and educational, not a philosophical movement, the attitude of most humanists towards scholastic philosophy was one of indifference; they seldom manifested outright hostility, and such opposition as they professed was not, for the most part, philosophical.

Humanists outside the university

The early humanists were, in fact, either independent men of letters or, more typically, members of the legal profession holding high office in church or state. Petrarch (1304–74) is the best-known representative of the first category. Famous nowadays for having written some of the most magnificent sonnets in the Italian language, he was known to his contemporaries primarily as a promoter of classical studies and the author of a number of highly regarded original works in Latin as well as a voluminous correspondence, likewise in Latin. An outstanding example of the second type of humanist is Petrarch's younger friend Coluccio Salutati (1331–1406), who was trained as a notary at Bologna University and for the last twenty-six years of his life held the office of chancellor in Florence.

Then, from the early fifteenth century onwards, many humanists became involved in education and left their stamp on generations of students, at first drawn predominantly from northern Italy, but in course of time from as far afield as England and Hungary.

Scholasticism and its means of expression

Medieval logic grew out of the school (university) curriculum; consequently, one characteristic vehicle of it was the commentary on a school-book. Medieval philosophers were not, in general, people who believed that the authoritative authors of the text-books were infallible or had said all that could be said about the relevant subjects, but they shared some convictions that can lead to that misimpression. In general they believed that (I) the auctores had laid down the right principles of the several disciplines and did not normally disagree over fundamental issues; (2) they had divided logic into its sub-disciplines in a reasonable way and taken care to provide posterity with treatises on all the main subjects; (3) therefore the right way to do logic was to reach a full understanding of those books and then proceed further in the footsteps of the auctores, remembering never to contradict them without fully explaining the necessity of doing so or – even better – showing that their text could be interpreted so as to make them say what they ought to have said; (4) Aristotle was the greatest of the auctores.

‘Scholastic’ properly characterises philosophers who approach their task in the way men did in medieval Western Europe, but scholasticism in this sense was neither a medieval nor a Western invention. It had flourished in the Greek-speaking part of the world between ca. A.D. 150 and 550, and medieval Latin scholasticism is not just a phenomenon comparable with its Greek predecessor, it is directly descended from it.

The medieval development of theories of war

In the preface to his Tree of Battles, written in 1387 and dedicated to Charles VI of France, Honoré Bouvet laments that ‘all holy Christendom is so burdened by wars and hatreds, robberies and dissensions, that it is hard to name but one little region, be it duchy or county, that enjoys good peace’. War was the normal condition of society in medieval Europe; and pessimistic doctors argued, on theological or astrological grounds, that ‘in this age it is necessary for there to be wars, and the slaughters and infinite sufferings of war’. Some men were dazzled by the pomp and circumstance of glorious war; a most doubtless agreed that ‘warres & bataylles shold be acursed thyng, & not due’.

About that cursed thing arose a prodigious literature – legal and theological, philosophical and practical, historical, strategical, and ecclesiastical. The centrepiece of the medieval discussions, to which they owe their abiding philosophical interest, is the theory of just war.

That theory is now most familiar from Aquinas' brief essay De hello (ST, Ilallae, q. 40); but in this instance Aquinas was no innovator: he stands in a long line of theorists, the fons et origo of whose ruminations is to be found in the writings of Augustine. The scattered observations of Augustine and his successors were collected and ordered by the canon lawyers of the twelfth century, whose work is best represented by Gratian's Decretum.

A revised dating of the eclipse

The view that the insights and developments of medieval logic were eclipsed during the fifteenth century by a humanist, rhetorically-oriented logic has long been popular, but it needs considerable revision and modification. In what follows I shall first give a brief account of what happened to the writing, teaching, and publication of logical works in the medieval style, by which I mean those which discuss such topics as consequences, in-solubles, exponibles, and supposition. I shall then examine in more detail what was actually said about certain medieval doctrines in the late fifteenth and sixteenth centuries in order to indicate both where logicians of the period had something new to contribute, and where there were departures from medieval doctrines which cannot be attributed to new logical insight. My conclusion will be that medieval logic as a living tradition did largely disappear, but that the eclipse dates from about 1530 (in so far as a specific date can ever sensibly be offered) rather than the mid fifteenth century.

Fifteenth-century logicians

After the death of Paul of Venice in 1429, the fifteenth century did not give rise to much important logical writing. There were various logicians in Italy who deserve mention for their contributions to logic in the medieval style, including Domenico Bianchelli (Menghus Blanchellus Faventinus), who wrote a long commentary on Paul of Venice's Logica parva; Paul of Pergula, who wrote on Ralph Strode's Consequentiae as well as producing his own Logica; and Gaetano di Thiene, who wrote on Strode, William Heytesbury, and Richard Ferrybridge.

Aristotle, Porphyry, and the old logic

Prominent among the antecedents of medieval philosophy, particularly of logic and philosophy of language, are two logical works of Aristotle's. His De interpretatione and Categories, as transmitted by Boethius and coloured by Porphyry's introduction (Isagoge) to the Categories, endowed the logica vetus with a substantial inheritance of technical terms and the metaphysical puzzles that go with them. An explanation of this inheritance requires a brief excursion into the history of the terminology central to the Isagoge and the Categories.

The terminology of the Isagoge and the Categories

Aristotle developed two loosely linked doctrines regarding the structure of propositions; one is that of the predicables, the other that of the categories (or predicaments). Chapters 4, 5, and 8 of Book I of Aristotle's Topics contain an account of the predicables definition, property, genus, differentia, and accident. A definition is a phrase signifying a thing's essence. A property is a predicate not indicating a thing's essence but predicable convertibly of it since it belongs to that thing alone; e.g., the capacity for literacy belongs exclusively to man, so that anything that has that capacity is a man, and only a man has that capacity. A genus is predicated essentially of diverse sorts of things; e.g., animal of man, ox, horse, and so forth. A differentia in combination with the genus produces the definition, as when mortal rational is added to animal to produce the definition of man.

Thirteenth-century criticism of Aquinas' Aristotelianism

Strong reaction among traditional theologians in Paris and Oxford against the massive introduction of new Aristotelian ideas was still growing at the time Albert, Thomas, and Siger taught and wrote. It culminated in the formal act of condemnation by Bishop Tempier in 1277. For a while the Averroistic trend was halted, and the main target of criticism was Thomas Aquinas. A conception of the soul too closely connected to the body, too near to matter was an offense against the entire Christian tradition, which derived so much from Platonism and Augustine. The criticism also attacked the concept of the potential and agent intellect. It rejected the potential nature of the intellect which received and did not produce cognition, it rejected the effect of sensible species on the intellect, and the independence attributed to human cognition, unassisted by divine illumination.

Reactions to the criticism

Even Thomas' pupils and defenders stepped back in the face of this overwhelming pressure. Giles of Rome, although he basically agreed with Thomas' conception of the potential and agent intellect, described the agent intellect also as a quasi-Avicennian storehouse of pre-empirical knowledge and rules of understanding, conceived of as complete potential knowledge. Godfrey of Fontaines defended Thomas in his Quodlibeta, written between 1285 and 1297, and gave his conception of the soul an even firmer Aristotelian character, but he denied the possibility that phantasmata can be turned into intelligible species by the agent intellect, and indeed eliminated intelligible species altogether as an element of intellective cognition.