bluuebunny/crossref_metadata_2025 huggingface dataset:
Technē
Authors: Brennan Tad
Published: September 2018

Technē (plural technai) is the ancient Greek term for an art or craft; examples include carpentry, sculpting and medicine. Philosophical interest in the technai stems from their use as a model and metaphor for all aspects of practical rationality, including its perfection in philosophy (the ‘art of living’). From Socrates onwards, the notion of technē is employed for thinking about the connections between reason, ends and action. Technai are held to possess epistemological virtues (such as coherence and explanatory power) and practical virtues (their delivering of detailed instructions for action) against which other bodies of belief or practical systems can be studied and judged.
Ailly, Pierre d’ (1350–1420)
Authors: Pluta Olaf
Published: September 2018

D’Ailly was a prolific writer on a number of subjects. His best known philosophical works concentrate on logic and on faith and reason, with strong influences from Ockham in particular. He also wrote influential works on the nature of the soul. He was one of the most eminent partisans of the late medieval nominalist movement and was numbered among the foremost doctores renovatores by King Louis XI in his decree against the nominalists. His works continued to be highly influential as late as the Reformation period.
Averroism
Authors: Ebbesen Sten
Published: September 2018

‘Averroism’, ‘radical Aristotelianism’ and ‘heterodox Aristotelianism’ are nineteenth- and twentieth-century labels for a late thirteenth-century movement among Parisian philosophers whose views were not easily reconcilable with Christian doctrine. The three most important points of difference were the individual immortality of human intellectual souls, the attainability of happiness in this life and the eternity of the world. An ‘Averroist’ or ‘Radical Aristotelian’ would hold that philosophy leads to the conclusions that there is only one intellect shared by all humans, that happiness is attainable in earthly life and that the world has no temporal beginning or end. Averroists have generally been credited with a ‘theory of double truth’, according to which there is an irreconcilable clash between truths of faith and truths arrived at by means of reason. Averroism has often been assigned the role of a dangerous line of thought, against which Thomas Aquinas opposed his synthesis of faith and reason. The term ‘Averroism’ is also used more broadly to characterize Western thought from the thirteenth through sixteenth centuries which was influenced by Averroes, and/or some philosophers’ self-proclaimed allegiance to Averroes.
Bernard of Tours (fl. 1147, d. before 1178)
Authors: Wetherbee Winthrop
Published: September 2018

Bernard of Tours, better known as Bernardus Silvestris, was closely acquainted with the major developments in science and theology which took place in the mid-twelfth century. His major work, the Cosmographia, an allegorical account of the creation of the universe and humankind, is dedicated to the philosopher-theologian Thierry of Chartres, who was probably also his teacher. However, Bernard himself was best known as a poet, and he seems to have made his living primarily as a teacher of grammar and rhetoric. His career perhaps reflects the fragmentation of the liberal arts curriculum in his day, including the segregation of literary studies from the increasingly specialized pursuit of the sciences.
Brinkley, Richard (fl. 1350–73)
Authors: Andrews Robert
Published: September 2018

Richard Brinkley was a Franciscan theologian at the University of Oxford in the latter half of the fourteenth century. Probably at the request of his superiors, he undertook an attack on nominalism and conceptualism, resulting in his best-known work, Summa logicae (Synopsis of Logic). Other works include a commentary on Peter Lombard’s Sentences, which survives only fragmentarily and in a student’s shortened version. Brinkley had a significant influence on several generations of Oxford logicians and Parisian theologians.
Buridan, John (c.1300–after 1358)
Authors: Zupko Jack
Published: September 2018

Unlike most other important philosophers of the scholastic period, John Buridan never entered the theology faculty but spent his entire career as an arts master at the University of Paris. There he distinguished himself primarily as a logician who made numerous additions and refinements to the Parisian tradition of propositional logic. These included the development of a genuinely nominalist semantics, as well as techniques for analyzing propositions containing intentional verbs and paradoxes of self-reference. Even in his writings on metaphysics and natural philosophy, logic is Buridan’s preferred vehicle for his nominalistic and naturalistic vision.

Buridan’s nominalism is concerned not merely with denying the existence of real universals, but with a commitment to economize on entities, of which real universals are but one superfluous type. Likewise, his representationalist epistemology accounts for the difference between universal and singular cognition by focusing on how the intellect cognizes its object, rather than by looking for some difference in the objects themselves. He differs from other nominalists of the period, however, in his willingness to embrace realism about modes of things to explain certain kinds of physical change.

Underlying Buridan’s natural philosophy is his confidence that the world is knowable by us (although not with absolute certainty). His approach to natural science is empirical in the sense that it emphasizes the evidentness of appearances, the reliability of a posteriori modes of reasoning and the application of certain naturalistic models of explanation to a wide range of phenomena. In similar fashion, he locates the will’s freedom in our evident ability to defer choice in the face of alternatives whose goodness appears dubious or uncertain.
Byzantine philosophy
Authors: Benakis Phil Linos
Published: September 2018

In Byzantium from the ninth century through to the fifteenth century, philosophy as a discipline remained the science of fundamental truths concerning human beings and the world. Philosophy, the ‘wisdom from without’, was invariably contrasted with the ‘philosophy from within’, namely theology. The view that philosophy is ‘the handmaiden of theology’, which the Greek Church Fathers derived from Philo and the Alexandrian school of theology, was not the dominant position in Byzantium as it was in the West; philosophy, and logic in particular, was never treated as a mere background to, or tool of, theology. By the same token, theology in Byzantium never developed into a systematic method of dialectical inquiry into Christian truths, or a science. Thus the initial distinction between philosophy and theology remained intact.

In terms of institutional practice, theological schools and studies did not exist in Byzantium and the main purpose of higher studies was to train state functionaries. This instruction, based on philosophy and the quadrivium, was mainly private, but it received support from the emperor and the church and we do hear of occasional interference by the secular or ecclesiastical authorities, perhaps because of professional or personal rivalries among the philosophy teachers. Furthermore, Byzantium had no independent universities or centers of study instituted by monastic orders as there were in the West, where social and political conditions were different.

Philosophy in Byzantium also steered clear of involvement in the theological controversies that arose from time to time. The prevalent model of the thinker in Byzantium was a sort of encyclopedic teacher of philosophy, an erudite scholar who kept in touch with the sciences of the quadrivium (arithmetic, geometry, astronomy and music) and other disciplines and set the philosophical tone of the scientific curricula. The development of philosophy in Byzantium was thus very different from that of Western scholasticism.
Carolingian renaissance
Authors: Marenbon John
Published: September 2018

The ‘Carolingian renaissance’ is the name given to the cultural revival in northern Europe during the late eighth and ninth centuries, instigated by Charlemagne and his court scholars. Carolingian intellectual life centred around the recovery of classical Latin texts and learning, though in a strictly Christian setting. The only celebrated philosopher of the time is Johannes Scottus Eriugena, but the daring Neoplatonic speculations of his masterpiece, the Periphyseon (On the Division of Nature) are not at all characteristic of the time and are based on Greek sources (Pseudo-Dionysius, Gregory of Nyssa, Maximus the Confessor) generally unknown to his contemporaries. The mainstream of Carolingian thought is important for the history of philosophy in three particular ways. First, it was at this time that logic first started to take the fundamental role it would have throughout the Middle Ages. Second, scholars began to consider how ideas they found in late antique Latin Neoplatonic texts could be interpreted in a way compatible with Christianity. Third (as would so often again be the case in the Middle Ages), controversies over Christian doctrine led thinkers to analyse some of the concepts they involved: for instance, the dispute in the mid-ninth century over predestination led to discussion about free will and punishment.
Clarembald of Arras (1110/20–c.1187)
Authors: Brown Stephen F.
Published: September 2018

A teacher of philosophy at Laon and commentator on Boethius, Clarembald was a product of the School of Chartres. His principal philosophical work, the Tractatulus (Short Treatise on Genesis), is an attempt to link Platonic theories of creation with the account given in Scripture, and includes a discussion of the nature of form and matter.
Damian, Peter (1007–72)
Authors: Mann William E.
Published: September 2018

Peter Damian is noted for his asceticism, contributions to church reform and literary style, the latter in writings that are primarily religious in character. Because of his hostility to the unbridled use of the disciplines of grammar and dialectic in religious matters, Damian is sometimes depicted as an opponent of philosophy. A more accurate assessment of his attitude is that the liberal arts, including philosophy, must remain subservient to religion. Damian’s major work De divina omnipotentia (On Divine Omnipotence) shows that he was willing and able to use philosophical argument in theology.
Alighieri, Dante (1265–1321)
Authors: Perler Dominik
Published: September 2018

Although Dante never received a systematic training in philosophy, he tackled some of the most controversial philosophical problems of his time. In his theory of science, he asked how we are to explain the fact that science is a unified, strictly ordered system of knowledge. He answered by comparing the scientific disciplines with the celestial spheres, claiming that the system of knowledge mirrors the cosmological order. In his political philosophy, he asked why all humans want to live in a peaceful society. All humans seek full use of their cognitive capacity, was his answer, and they can achieve it only if they interact socially. In his philosophy of nature, Dante asked what brings about the order of the elements, and suggested that the elements obey the laws of a universal nature in a strictly ordered cosmos. He elaborated all his answers in a scholastic framework that made use of both Aristotelian and Neoplatonic traditions.
Eternity of the world, medieval views of
Authors: Thijssen J.M.M.H.
Published: September 2018

The problem of the eternity of the world was much debated in Western philosophy from the twelfth through the fourteenth centuries, but its history goes back as far as Philo of Alexandria and the Church Fathers. The principal topic of controversy was the possibility of a beginningless and yet created world. The arguments that fashioned the medieval discussion rested upon assumptions concerning the concepts of eternity and creation. In addition, the issue of eternity intertwined with discussions of the relationship of God to creation, with proofs of the existence of God, with the nature of the material universe and with the nature of infinity. Some of the most ingenious ideas in these debates were obtained from pagan Greek, Islamic and Jewish traditions.
Francis of Meyronnes (d. after 1325)
Authors: Hause Jeffrey
Published: September 2018

Francis of Meyronnes, the doctor illuminatus (Enlightened Doctor), was called the ‘Prince of the Scotists’ for his work in systematizing and propagating the philosophy of Duns Scotus in the fourteenth century. His work in metaphysics and theology, while heavily dependent on Scotus, shows originality and independence of mind, and is characterized by his dedication to finding rational defences of Catholic doctrine. His discussion of Ideas includes a critique of Aristotelian metaphysics, and he argues instead for a position based on his conception of Platonism.
Godfrey of Fontaines (c.1250–c.1306/9)
Authors: Wippel John F.
Published: September 2018

Godfrey of Fontaines studied philosophy and theology at the University of Paris and subsequently taught theology there. A theologian by profession, he developed a highly interesting philosophy, especially a metaphysics. For Godfrey, metaphysics studies being as being. Being itself is divided into cognitive being and real being, and real being is divided into being in act and being in potency. In finite beings, essence and existence are neither really distinct nor intentionally distinct; they are identical. Human reason can prove that God exists, and reach some imperfect knowledge concerning what God is, but cannot prove that the world began to be. For Godfrey, corporeal entities in this world are composed of matter and form, but heavenly bodies probably lack prime matter. On philosophical grounds, he favours the theory that there is only one substantial form in human beings – the intellective soul – but for theological reasons leaves this question open. His philosophy is somewhat more Aristotelian and less Neoplatonic than that of most of his contemporaries.
Henry of Ghent (early 13th century–1293)
Authors: Marrone Steven P.
Published: September 2018

Perhaps the most influential theologian between Thomas Aquinas and Bonaventure in the third quarter of the thirteenth century and John Duns Scotus at the beginning of the fourteenth century, Henry of Ghent stands at a turning point in scholastic philosophy. He was a defender of traditional Neoplatonic positions and has often been seen as the epitome of thirteenth-century Augustinianism. Yet his convoluted metaphysics and a theory of knowledge weaving together Neoplatonic and Aristotelian strands inspired novel philosophical trends in the fourteenth century, particularly among Franciscan thinkers. His work thus constituted the point of departure for scholastic giants like Duns Scotus and William of Ockham, who not only used him as a foil against which to articulate their own system of thought but also absorbed much of his fundamental philosophical outlook and terminology.

Characteristic of Henry’s metaphysics was an essentialism so pronounced that critics accused him of positing a realm of essences separate from worldly actuality. In his defence, Henry insisted that essences, though prior to actual existence, were separate only as grounded in the divine exemplars of things, but the Platonism of his approach struck his contemporaries as extraordinary nonetheless. Ironically, Henry’s understanding of essence as congruent with intellectual coherence provided an opening for a more logic-based analysis of modality, especially possibility, in succeeding thinkers such as Duns Scotus.

The emphasis on essence re-emerged in Henry’s theory of knowledge, and at least in his early writings he offered a vision of knowing truth through divine illumination often taken as paradigmatic of medieval Augustinianism. Even his later attempts to cast epistemology in a more Aristotelian light retained the insistence that true knowledge somehow entails access to the exemplary essences in God’s mind. The same essentialism led Henry to formulate what he called an a priori proof for God’s existence, best approximation in the thirteenth century to Anselm’s ontological argument. Again, however, Henry’s Augustinianism provided an unintended springboard for innovation, leading to Duns Scotus’ theory of the univocity of being and metaphysical proof of God’s existence.
Henry of Harclay (c.1270–1317)
Authors: Molland George
Published: September 2018

An English philosopher of the early fourteenth century, Harclay moved away from the position of Duns Scotus on the extramental existence of universals and towards the more conceptualist or nominalist stance of William of Ockham. On questions of infinity and continuity, Henry was strongly anti-Aristotelian, holding that there were numbers that were actually infinite and not all equal to each other, and that a continuum was composed of an actual infinity of indivisibles, by which it was properly measured. His position came under powerful mathematical attack.
Joachim of Fiore (c.1135–1202)
Authors: Murphy Sean Eisen
Published: September 2018

Joachim was a charismatic monastic reformer and inventive scriptural exegete whose study of the Bible led him to propound complex theories of history. Especially interested in the Apocalypse as a guide to history, he believed that the advent of the Antichrist and a violent end of the age were imminent. Contemporaries considered him a prophet, and this reputation – furthered by spurious works attributed to him – endured for four centuries. His theology, however, was widely criticized by such authoritative thinkers as Aquinas, Bonaventure and Bradwardine.
John of La Rochelle (d.1245)
Authors: Jordan Mark D.
Published: September 2018

John of La Rochelle was one of the first generation of Franciscan theologians at the University of Paris. What little is known of his life places him as a close partner to the greatest of the early Franciscan teachers, Alexander of Hales. John collaborated with Alexander not only in steering the Franciscan order towards some sort of institutional equilibrium, but also in the elaboration of the first synthesis of Franciscan theology, the Summa Fratris Alexandri (Summa of Brother Alexander). Whole sections of the Summa were written by John, most notably the treatment of moral law. John wrote in his own voice a number of theological works and two books on the soul, the Tractatus de divisione multiplici potentiarum animae (Treatise on the Multiple Division of the Soul’s Power) and the Summa de anima (Summa on the Soul).
John of Mirecourt (fl. c.1345)
Authors: Somerset Fiona
Published: September 2018

The traditional view that John of Mirecourt was condemned because he was a radical sceptic has been brought into question by more extensive research on his writings. For example, it appears that he did not doubt the existence of God as he was accused of doing. John was, however, greatly interested in describing as accurately as possible the kinds of evidence that lead to knowledge and the means by which they are produced.
John of Paris (c.1260–1306)
Authors: Jordan Mark D.
Published: September 2018

John of Paris was a prominent Dominican theologian at Paris at the end of thirteenth century. He began his career with polemical works in defense of Thomist positions. In them, he asserts the distinction between essence and existence, the unity of substantial form and the function of matter as principle of bodily individuation. John later took part in wider controversies, including those between the French crown and the papacy. His best known work is a treatise on the mutual independence of secular and spiritual authority.
Kilwardby, Robert (d. 1279)
Authors: Conti Alessandro D.
Published: September 2018

Robert Kilwardby is one of the most remarkable thinkers of the thirteenth century. He is the champion of the traditional approach to philosophy and theology, which developed the body of doctrines worked out by Augustine. His activity is set in the very crucial period of middle scholasticism, when the diffusion of Aristotle’s philosophical system and its utilization for Christian theology caused a sharp conflict between the followers of the Patristic tradition, such as Kilwardby or the members of the Franciscan school, and the new theologians, such as Thomas Aquinas, who tried to express the contents of divine revelation within the Aristotelian paradigm. Kilwardby used all of his intellectual resources and ecclesiastical authority in fighting against this new trend and in defending Augustinianism, whose main theses (for example, a plurality of substantial forms in composite substances, the presence of seminal reasons in matter, universal hylomorphism, individuation by matter and form, a conceptual distinction between the soul and its faculties, and the necessity of divine illumination in order to grasp the eternal truths) he supports in his writings.
Liber de causis
Authors: Jarka-sellers Hannes
Published: September 2018

The Liber de causis (Book of Causes) is a short treatise on Neoplatonist metaphysics, composed in Arabic by an unknown author probably in the ninth century in Baghdad. Through its twelfth-century Latin translation, it greatly influenced mature medieval philosophy in the West.

Drawing heavily on the Greek Neoplatonist Proclus, the Liber de causis represents a development of late Neoplatonism along two lines. On the one hand, the author modifies and simplifies Proclus’ theory of causes to accord more closely with the three-part division of ultimate causes advanced by the founder of Neoplatonism, Plotinus. On the other hand, the author introduces some of the metaphysical principles of Qu’ranic or biblical monotheism. The result is a metaphysically provocative reinterpretation of Neoplatonist thought which, because it seemed to accommodate Platonist philosophy to the medieval worldview, made the Liber de causis a natural source text for medieval philosophers.
Lombard, Peter (1095/1100–1160)
Authors: Colish Marcia L.
Published: September 2018

Peter Lombard’s philosophical views are important given the formative role his Sententiae in IV libris distinctae (Four Books of Sentences) played in the education of university theologians in the high Middle Ages, many of whom were also philosophers. Peter staunchly opposes theologies, cosmologies and anthropologies of a Platonic or Neoplatonic type. While conversant with new trends in logic in his day, he is disinclined to treat theological issues as illustrations of the rules of formal logic or natural philosophy, preferring to view them from a metaphysical perspective. In his doctrine of God he deliberately eschews terminology associated with any one philosophical school. In his anthropology and sacramental theology he shows a marked preference for Aristotelianism. The hospitability of his theology to Aristotelianism and to a philosophical treatment of a range of theological questions made his Sentences elastic enough to accommodate the reception of Greco-Arabic thought and to serve as a pedagogical framework usable by philosophers of every persuasion during the succeeding three centuries.
Llull, Ramon (1232–1316)
Authors: Johnston Mark D.
Published: September 2018

One of the most extraordinary figures of thirteenth-century Europe, Llull was a self-taught lay theologian and philosopher, chiefly concerned with reforming Christian society and converting unbelievers. Details of his life remain obscure, but over 200 of his writings survive. Most of these expound his personal dialectical system, the Great Universal Art of Finding Truth, an encyclopedic collation of commonplace doctrines that attempts to show how all human knowledge conforms to divine truth. Largely ignored during Llull’s lifetime and denounced as heretical in the later Middle Ages, the Great Art became very popular in the Renaissance as a programme of universal knowledge.
Marius Victorinus (fl. 4th century AD)
Authors: Kenney John Peter
Published: September 2018

Gaius Marius Victorinus was a rhetorician active in Rome in the fourth century ad. Classically educated and with an interest in philosophy, he converted to Christianity late in life and transferred his philosophical interests to Christian works. Strongly influenced by Neoplatonism, particularly by the works of Plotinus and Porphyry, he sought to articulate Christian concepts such as the Trinity in Neoplatonic terms. His writings on the Trinity and the soul influenced Augustine and other patristic philosophers.
Marsilius of Inghen (1330–96)
Authors: Bos E.P.
Published: September 2018

The theological and philosophical works of Marsilius of Inghen are characterized by a logico-semantical approach in which he followed John Buridan, combined with an eclectic use of older theories, often dating from the thirteenth century. These were sometimes more Aristotelian and sometimes more Neoplatonist. The label ‘Ockhamist’, which is often applied to Marsilius, has therefore limited value. He was influential on Central European philosophy of later centuries, both through his own philosophy and by the way he stimulated reform of university programmes. In the sixteenth century there were still references to a ‘Marsilian way’ in logic and physics.
Marsilius of Padua (1275/80–1342/3)
Authors: McGrade A.S.
Published: September 2018

Marsilius of Padua’s Defensor pacis (Defender of Peace), written in 1324, is the most revolutionary political treatise of the later Middle Ages. Discourse One of the Defensor pacis can plausibly be read as a complete theory of the secular state. In a much longer second discourse, Marsilius attacks papal and priestly political power, which, especially in the claims to ‘fullness of power’ (plenitudo potestatis) sometimes made for the papacy, he presents as a major threat to civic tranquillity. The distinctive features of Marsilian theory are (a) its emphasis on broad participation in the legislative process as a guarantee of sound law, and (b) its insistence that supreme coercive power in any community must be held by a single, secular, popularly authorized ‘ruling part’ (pars principans).
Oxford Calculators
Authors: Sylla Edith Dudley
Published: September 2018

‘Oxford Calculators’ is a modern label for a group of thinkers at Oxford in the mid-fourteenth century, whose approach to problems was noticed in the immediately succeeding centuries because of their tendency to solve by ‘calculations’ all sorts of problems previously addressed by other methods. If for example the question was, what must a monk do to obey the precept of his abbot to pray night and day, a ‘calculator’ might immediately rephrase the question to ask whether there is a minimum time spent in prayer that would be sufficient to fulfil the abbot’s precept, or a maximum time spent that would be insufficient to fulfil the precept. Or, if grace was supposed to be both what enables a Christian to act meritoriously and a reward for having so acted, then a calculator might ask whether the degree of grace correlated with a meritorious act occurs at the moment of the meritorious act, before the act when the decision to act is being made, or after the act when the reward of increased grace is given. If a body was hot at one end but cold at the other, then a calculator might ask not whether it is to be labelled hot or cold, but how hot it is as a whole. Finally, if it was asked whether a heavy body acts as a whole or as the sum of its parts, then a calculator might take the case of a long thin rod falling through a tunnel pierced through the centre of the earth and attempt to calculate how the rod’s velocity would decrease as parts of the rod passed the center of the cosmos, if it acted as the sum of its parts.

Of these four questions, the last two were asked by Richard Swineshead, a mid-fourteenth century fellow of Merton College, Oxford, whose Liber calculationum (Book of Calculations) led to his being given the name ‘Calculator’. By association with Richard Swineshead, other Oxford masters including Thomas Bradwardine, Richard Kilvington, William Heytesbury, Roger Swineshead and John Dumbleton have been labelled the ‘Oxford Calculators’. Their work contains a distinctive combination of logical and quantitative techniques, which results from the fact that it was often utilized in disputations on sophismata (de sophismatibus). This same group of thinkers, with emphasis on their mathematical rather than logical work, has been called the ‘Merton School’, because many but not all of the Calculators were associated with Merton College, Oxford. Besides calculatory works, the same authors wrote works in which calculatory techniques are not so prominent, including commentaries on Aristotle, mathematical compendia and commentaries on Peter Lombard’s Sentences.
Philip the Chancellor (1160/85–1236)
Authors: MacDonald Scott
Published: September 2018

Philip occupies a pivotal place in the development of medieval philosophy. He is among the very first in the Latin West to have a fairly complete picture of both the newly available natural philosophy and metaphysics of Aristotle and the work of the great Muslim thinkers, Avicenna and Averroes. His Summa de bono, composed sometime between 1225 and 1236, shows the broadening of philosophical interests and the growth of philosophical sophistication that accompanied reflection on these new materials. Philip’s Summa had a major impact on subsequent thirteenth-century thinkers, particularly Albert the Great, whose own Summa de bono is closely modelled on that of Philip.
Platonism, medieval
Authors: Moran Dermot
Published: September 2018

Medieval Platonism includes the medieval biographical tradition, the transmission of the dialogues, a general outlook spanning commitment to extramental ideas, intellectualism in cognition, emphasis on self-knowledge as the source of philosophizing, and employment of the dialogue form. Platonism permeated the philosophy of the Church Fathers, the writings of Anselm and Abelard, the twelfth-century renaissance, the Italian Renaissance and the northern renaissance. Indeed the mathematical treatment of nature, which inspired the birth of modern science in the works of Kepler and Galileo, stems in part from late medieval Pythagorean Platonism.

The term ‘Platonism’ is of seventeenth-century origin. Medieval authors spoke not of Platonism but rather of Plato and of Platonists (platonici), applying the term ‘Platonist’ to an extreme extramental realism about universals, or a commitment to the extramental existence of the Ideas. Thus John of Salisbury characterized Bernard of Chartres as ‘the foremost Platonist of our time’ in regard to his theory of ideas. For Aquinas, Platonists hold an overly intellectualist account of human knowledge, ignoring the mediation of the senses. In general, medieval writers agreed with Cassiodorus’ maxim, Plato theologus, Aristoteles logicus. Plato was primarily a theologian, an expert on the divine, eternal, immaterial and intelligible realm, a classifier of the orders of angelic and demonic beings, whereas Aristotle was primarily a logician and classifier of the forms of argument.

Medieval Platonism combines elements drawn from Middle Platonism and Neoplatonism. It generally assumes a dualistic opposition of the divine and temporal worlds, with the sensible world patterned on unchanging immaterial forms, often expressed as numbers. It also affirms the soul’s immortality and direct knowledge of intelligible truths, combined with a suspicion of the mortal body and a distrust of the evidence of the senses. Neoplatonists sympathized with Porphyry’s aim (in his lost De harmonia Platonis et Aristotelis) of harmonizing Plato with Aristotle. A Platonic outlook (largely inspired by the Timaeus) dominates the early Middle Ages from the sixth to twelfth centuries, whereas the thirteenth and fourteenth centuries, the age of scholasticism, witnessed an explosion in the knowledge of Aristotelian texts, often transmitted through Arabic intermediaries. The new interest in Aristotle was such that, although the Timaeus was widely lectured on during the twelfth and early thirteenth centuries, by 1255 it was no longer required reading at the University of Paris. Interest in Plato re-emerged in the Italian Renaissance with the availability of genuine works of Plato, Plotinus and Proclus. Nevertheless, through Pseudo-Dionysius in particular, Platonism reverberates in many thirteenth-century authors, especially in theology.
Pseudo-Dionysius (fl. c. AD 500)
Authors: Jarka-Sellers Hannes
Published: September 2018

‘Pseudo-Dionysius’ was a Christian Neoplatonist who wrote in the late fifth or early sixth century and who presented himself as Dionysius the Areopagite, an Athenian converted by St Paul. This pretence – or literary device – was so convincing that Pseudo-Dionysius acquired something close to apostolic authority, giving his writings tremendous influence throughout the Middle Ages and into the Renaissance.

The extant four treatises and ten letters articulate a metaphysical view of the cosmos, as well as a religious path of purification and perfection, that are grounded in the Neoplatonism developed in the Platonic Academy in Athens. Although this strand of Neoplatonist thought, in contrast to that developed at the school in Alexandria, was deliberately pagan in its religious orientation, Pseudo-Dionysius used its conceptual resources (drawing especially on Proclus) to give precision and depth to the philosophical principles of a Christian world view. Cardinal points of Pseudo-Dionysius’ thought are the transcendence of a first cause of the universe, the immediacy of divine causality in the world and a hierarchically ordered cosmos.
Roscelin of Compiègne (c.1050–after 1120)
Authors: Tweedale Martin M.
Published: September 2018

Roscelin of Compiègne was one of a group of logicians in late eleventh and early twelfth-century Europe who, in defiance of most of their predecessors in the field, treated logic as dealing with the concrete physical things that serve as verbal signs of realities rather than the realities those signs signified. This meant that although the things logic talks about are part of the physical world, it talks about them not as things referred to by language but as parts of language itself. All the technical notions of Aristotelian logic, for example ‘universal’, ‘individual’, ‘category’, ‘genus’ and ‘species’, apply only to those linguistic signs themselves qua signs.
Suso, Henry (c.1295–1366)
Authors: Bussanich John
Published: September 2018

Suso was a Dominican friar and mystic and, with his friend John Tauler, a student of Master Eckhart. The three form the nucleus of the Rhineland school of mysticism. As a lyric poet and troubadour of divine wisdom, Suso explored with psychological intensity the spiritual truths of Eckhart’s mystical philosophy. His devotional works were extremely popular in the later Middle Ages.
Tauler, John (c.1300–1361)
Authors: Bussanich John
Published: September 2018

Tauler was a Dominican preacher and mystic, the author of seventy-nine vernacular sermons which presented the Neoplatonic speculative mysticism of his teacher Eckhart in more personal and concrete terms. Tauler greatly influenced late medieval mendicant spirituality, Luther, and the German pietists and romantics. His primary aims were to inculcate the spiritual virtues and devotion to God.
Thierry of Chartres (fl. c.1130–50)
Authors: Marenbon John
Published: September 2018

Thierry of Chartres, who taught at Paris and Chartres in the mid-twelfth century, was a polymath and a Platonist. The Heptateuchon, a large and ambitious collection of texts for teaching the liberal arts, testifies to the range of his interests from grammar, logic and rhetoric to mathematics and astronomy; they also stretched to theology. To Thierry is attributed an explanation of the account of creation in Genesis, after God’s initial action, in physical terms. He also used arithmetical analogies to illustrate the Trinity and, drawing on a variety of Platonic and Neoplatonic sources, analysed the relationship between God and his creation.
Translators
Authors: Brams Jozef
Published: September 2018

Translators played a crucial role in the history of medieval philosophy. Since multilingualism was generally restricted to places in which a direct contact between different languages was possible, such as Byzantium, the Near East, southern Italy or Spain, the dissemination of knowledge into foreign cultures was mainly brought about by means of translation. In this conversion process various kinds of writings were involved, including the Bible, the Qur’an and liturgical and hagiographic works as well as literary and historiographic texts.
William of Sherwood (c.1200/5–c.1266/75)
Authors: Longeway John
Published: September 2018

William of Sherwood, an English logician of the mid-thirteenth century, is most noted for his theories of supposition and syncategorematic terms. In application, these theories enable us to express the true logical form of sentences with misleading grammatical forms. William’s Insolubilia (Insolubles) deals with paradoxes of self-reference, such as ‘I am now uttering a falsehood’.
Wodeham, Adam (c.1298–1358)
Authors: Wood Rega
Published: September 2018

An English Franciscan theologian, Wodeham was preoccupied with logical and semantic questions. He lectured for about a decade on Peter Lombard’s Sentences, first at London, then at Norwich and finally at Oxford. His lectures emphasized the dependence of the created world on God and the contingency of nature and salvation.

John Duns Scotus and William of Ockham exerted the most important influences on Wodeham. He regarded Scotus as a vigorous thinker and respected him enough to accept his opinion in case of doubt. Proud to have learned logic from Ockham, Wodeham devoted considerable time to defending Ockham’s views from Walter Chatton, whom he saw as someone whose errors in logic arose from malice as well as ignorance. However, despite Wodeham’s reservations about Chatton, he was considerably influenced by him. Similarly, Wodeham modified his own opinion about sensory illusions in response to Peter Aureol, whom he saw as skilled and prudent but often mistaken, sometimes as a result of faulty logic.
Wyclif, John (c.1330–84)
Authors: Catto Jeremy
Published: September 2018

John Wyclif was a logician, theologian and religious reformer. A Yorkshireman educated at Oxford, he was first prominent as a logician; he developed some technical notions of the Oxford Calculators, but reacted against their logic of terms to embrace with fervour the idea of the real existence of universal ideas. He expounded his view as a theologian, rejecting the notion of the annihilation of substance (including the eucharistic elements) and treating time as merely contingent. The proper understanding of universals became his touchstone of moral progress; treating scripture as a universal idea, he measured the value of human institutions, including the Church and its temporal property, by their conformity with its absolute truth. These views, though temporarily favoured by King Edward III, were condemned by Pope Gregory XI in 1377 and by the English ecclesiastical hierarchy in 1382, forcing him into retirement but leaving him the inspirer of a clandestine group of scholarly reformers, the Lollards.
Denys the Carthusian (1402/3–71)
Authors: Emery Kent
Published: September 2018

Denys de Leeuwis was born in the village of Rijkel, in modern Belgium. In 1421 he matriculated at the University of Cologne, where he received the Master of Arts degree in 1424. There he followed ‘the way of Thomas Aquinas’, whom he calls his ‘patron’ in his early works. Later Denys adopted ‘Albertist’ against ‘Thomist’ positions on a number of philosophical issues. After leaving the University, he entered the Carthusian monastery in Roermond, where, save for brief periods, he spent the rest of his life. He corresponded with Nicholas of Cusa and dedicated two or three works to him. Denys was a voracious reader of the ancient and medieval philosophers whose writings were available in Latin, and of scholastic theologians. Because of his extensive references to authorities, historians often call him ‘eclectic’. Yet from his sources he educes his own distinctive philosophy. Like Albert the Great, Denys practised philosophy and theology by paraphrasing and analysing their histories.
Agrippa von Nettesheim, Henricus Cornelius (1486–1535)
Authors: Keefer Michael H.
Published: September 2018

Famous in the sixteenth century for writings in which he steps forward variously as magician, occultist, evangelical humanist and philosopher, Agrippa shared with other humanist writers a thoroughgoing contempt for the philosophy of the scholastics. In his more evangelical moods Agrippa could be taken for a radical exponent of the philosophia Christi of his older contemporary Erasmus, or mistaken for a follower of Luther, whose early writings he actively disseminated in humanist circles. However, his deepest affinities are with magically inflected philosophies: the Neoplatonism and Hermetism of Marsilio Ficino, and the syncretic Christian Kabbalah of Giovanni Pico della Mirandola, Johannes Reuchlin and Johannes Trithemius.

As well as expounding an influential magical view of language, Agrippa contributed to the sixteenth-century revival of scepticism, denounced the ‘tyranny’ of those who obstructed a free search for truth, criticized the subjection of women and (with a courage unusual in his time) resisted and mocked the instigators of the witch-craze. Finding in Hermetic–Kabbalistic doctrines the inner truth both of religion and of philosophy, Agrippa was also aware of parallels between these magical doctrines and the Gnostic heresies. His heterodoxy made him a target for pious slanders: within several decades of his death he became the protagonist of demonological fictions which were soon absorbed into the legend of Dr Faustus.
Bruno, Giordano (1548–1600)
Authors: Ashworth E.J.
Published: September 2018

Giordano Bruno was an Italian philosopher of nature and proponent of artificial memory systems who abandoned the Dominican Order and, after a turbulent career in many parts of Europe, was burned to death as a heretic in 1600. Because of his unhappy end, his support for the Copernican heliocentric hypothesis, and his pronounced anti-Aristotelianism, Bruno has often been hailed as the proponent of a scientific worldview against supposed medieval obscurantism. In fact, he is better interpreted in terms of Neoplatonism and, to a lesser extent, Hermeticism (also called Hermetism). Several of Bruno’s later works were devoted to magic; and magic may play some role in his many books on the art of memory. His best-known works are the Italian dialogues he wrote while in England. In these Bruno describes the universe as an animate and infinitely extended unity containing innumerable worlds, each like a great animal with a life of its own. His support of Copernicus in La Cena de le ceneri (The Ash Wednesday Supper) was related to his belief that a living earth must move, and he specifically rejected any appeal to mere mathematics to prove cosmological hypotheses. His view that the physical world was a union of two substances, Matter and Form, had the consequence that apparent individuals were merely collections of accidents. He identified Form with the World-Soul, but although he saw the universe as permeated by divinity, he also believed in a transcendent God, inaccessible to the human mind. Despite some obvious parallels with both Spinoza and Leibniz, Bruno seems not to have had much direct influence on seventeenth-century thinkers.
Cajetan (Thomas de Vio) (1468–1534)
Authors: Mahoney Edward P.
Published: September 2018

Thomas de Vio, better known as Cajetan, has long been considered to be the outstanding commentator on the philosophical thought of Thomas Aquinas. He has had a great influence not only on discussions about Aquinas’ theory of analogical predication regarding God and creatures but also on discussions about Aquinas’ fundamental notions of essence and existence. On both counts his interpretations are at variance with Aquinas himself. He also set himself in opposition to Aquinas when he denied in his later writings that the immortality of the human soul could be demonstrated, arguing that it is a doctrine that must be accepted simply on faith, like the doctrines of the Trinity and the Incarnation. His explication of Aquinas’ cognitive psychology is an interesting development that goes beyond Aquinas.
Campanella, Tommaso (1568–1639)
Authors: Headley John M.
Published: September 2018

Tommaso Campanella was a Counter-Reformation theologian, a Renaissance magus, a prophet, a poet and an astrologer, as well as a philosopher whose speculations assumed encyclopedic proportions. As a late Renaissance philosopher of nature, Campanella is notable for his early, and continuous, opposition to Aristotle. He rejected the fundamental Aristotelian principle of hylomorphism, namely the understanding of all physical substance in terms of form and matter. In its place he appropriated Telesio’s understanding of reality in terms of the dialectical principles of heat and cold; and he adopted a form of empiricism found in Telesio’s work that included pansensism, the doctrine that all things in nature are endowed with sense. Especially after 1602, Campanella’s exposure to Renaissance Platonism also involved him in panpsychism, the view that all reality has a mental aspect. Thus his empiricism came to show a distinctly metaphysical and spiritualistic dimension that transformed his philosophy. At the same time his epistemology embraced a universal doubt and an emphasis on individual self-consciousness that are suggestive of Descartes’ views.

Campanella’s career as a religious dissident, radical reformer and leader of an apocalyptic movement presents a political radicalism that was oddly associated with more traditional notions of universal monarchy and the need for theocracy. The only one of his numerous writings that receives attention today, La Città del Sole (The City of the Sun) (composed 1602, but not published until 1623), has come to occupy a prominent place in the literature of utopias though Campanella himself seems to have expected some form of astronomical/apocalyptic realization.

Campanella’s naturalism, especially its pansensism and panpsychism, enjoyed some currency in Germany and France during the 1620s, but in the last five years of his life it was emphatically rejected by the intellectual communities headed by Mersenne and Descartes, as well as by Galileo.
Capreolus, Johannes (c.1380–1444)
Authors: Tavuzzi Michael
Published: September 2018

Thomist philosopher and theologian, Capreolus composed a lengthy commentary on Aquinas’ work on Peter Lombard’s Sentences, known as Defensiones theologiae divi Thomae Aquinatis (Defences of the Theology of Thomas Aquinas) (first printed in 1483–4). He sought to refute the criticisms of Thomism by competing scholastic traditions during the fourteenth century. The Thomistic school was so impressed with Capreolus’ achievement that it came to refer to him as Princeps Thomistarum (leader of the Thomists). Twentieth-century Thomists have, generally, considered him more faithful to the teachings of Aquinas than later commentators such as Cajetan. His philosophical opinions which have received most attention concern analogy, the formal ontological constituent of the person and the individuation of material substances.