Ockham, William of
OCKHAM, WILLIAM OF
(b. Ockham, near London, England, ca. 1285; d. Munich, Germany, 1349)
philosophy, theology, political theory.
Traditionally regarded as the initiator of the movement called nominalism, which dominated the universities of northern Europe in the fourteenth and fifteenth centuries and played a significant role in shaping the directions of modern thought, William of Ockham ranks, with Thomas Aquinas and Duns Scotus, as one of the three most influential Scholastic philosophers. Of his early life nothing is known; but it is supposed that he was born in the village of Ockham, Surrey, between 1280 and 1290 and that he became a Franciscan friar at an early age. He entered Oxford around 1310 as a student of theology and completed his formal requirements for the degree by lecturing on Peter Lombard’s Sentences in the years 1318–1319, thereby becoming a baccalaureus formatus, or inceptor. During the next four years, while awaiting the teaching license which would have made him a magister actu regens, or doctor of theology, Ockham took part in quodlibetal disputations, revised his lectures on the first book of the Sentences for public circulation, and wrote some philosophical and theological treatises.
In this period his teachings, recognized for their power and originality, became a center of controversy and aroused opposition from partisans of Duns Scotus, whose doctrines Ockham criticized, as well as from most of the Dominican masters and some of the secular teachers. In 1323 one of the latter, John Lutterell, went to the papal court at Avignon to press charges of heretical teaching against Ockham, who was summoned to Avignon to answer these accusations early in 1324. Because his academic career was cut short by these events, so that he never received his license to teach, he came to be known as “the venerable inceptor”—that is, candidate who never received the doctoral degree he had earned.
At Avignon, Ockham stayed at the Franciscan convent while awaiting the outcome of the process against him; and during this period he probably wrote several of his theological and philosophical works. A commission of six theologians was appointed by Pope John XXII to examine the charges against his teaching; and although this commission drew up two lists of suspect doctrines, no action appears to have been taken on the charges. Meanwhile Ockham became actively involved in the dispute then raging between Michael of Cesena, general of the Franciscan order, and Pope John XXII over the question of evangelical poverty; and he gave his support to Cesena.
When, in May 1328, it became apparent that the pope was about to issue an official condemnation of their position, Cesena, Ockham, and two other Franciscan leaders fled by night from Avignon and sought the protection of the German emperor, Louis of Bavaria. Louis, whose claim to the imperial crown was contested by Pope John, welcomed the support of Ockham in his cause, as well as that of Marsilius of Padua. The pope, enraged by this defection, excommunicated Ockham and his companions, not for heretical doctrines but for disobedience to his authority. During the ensuing years Ockham remained at Munich and devoted his energies to writing a series of treatises and polemical works directed against John XXII, some of which contained carefully argued discussions of the powers and functions of the papal office, the church, and the imperial or civil authority. When Louis of Bavaria died in 1347, the contest with the Avignon papacy became a lost cause; and there is some evidence that Ockham sought to reconcile himself with the Franciscan faction that had remained loyal to the pope. It is thought that he died in 1349, a victim of the Black Plague, and that he was buried in the Franciscan church at Munich.
Ockham’s writings, as preserved, fall into three main groups: philosophical, theological, and political. The philosophical works include commentaries and sets of questions on Aristotle’s Physics and commentaries on Porphyry’s Predicables and Aristotle’s Categoriae, De interpretatione, and De sophisticis elenchis. Ockham wrote an independent work on logic, entitled Summa logicae, that gave full expression to his own philosophy of language and logical doctrines. An incomplete treatise, published under the title Philosophia naturalis, dealt with the concepts of motion, place, and time in an original and independent manner. Of his theological writings the most important is the set of questions on book I of the Sentences, edited by Ockham for publication and therefore known as his ordinatio, along with the questions on the other three books, which are in the form of reportata(stenographic versions of the lectures as actually delivered). The Quodlibeta septem, containing 172 questions on theological and philosophical topics divided among seven quodlibetal disputations, are of great value as an expression of Ockham’s distinctive philosophical positions.
Of logical as well as theological interest are the treatise De praedestinatione et de praescientia dei et de futuris contingentibus and the work known as De sacramento altaris, which seems to consist of two distinct treatises and which is devoted chiefly to arguing that the doctrine of transubstantiation does not require the assumption that quantity is an entity distinct from substances or qualities. One other theological work, the authenticity of which has been questioned, is the Centiloquium theologicum, consisting of 100 conclusions directed mainly to showing that doctrines of natural theology cannot be proved by evident reason or experience.
The third group of Ockham’s writings is made up of the polemical and political works written in his Munich period. Many of these are of interest only in connection with the historical events of the time; but some of them contain important discussions of moral, legal, and political concepts and issues developed in connection with the controversies over the powers of pope and emperor, of church and state. Such are the lengthy Dialogus inter magistrum et discipulum de imperatorum et pontificum potestate, the Octo quaestiones super potestate et dignitate papali, and the shorter but eloquent Tractatus de imperatorum et pontificum potestate, written in 1347. Modern critical editions of the political works are well under way; but editions of the philosophical and theological writings are very much needed, since the early printed editions are both rare and not fully reliable, while some important works (those on Aristotle’s Physics) have never been printed at all.
Ockham was a thinker of profound originality, independence, and critical power. Although he had scarcely any acknowledged disciples, and did not found a school in the sense of having followers committed to defense of his teachings (as did Thomas Aquinas and Duns Scotus), the actual influence exerted by Ockham’s thought, in his own time and into the seventeenth century, was of a significance and breadth that may well have surpassed that of Aquinas or Scotus. This influence is clearly discernible in the empiricist doctrines of Locke and Hume, in the controversies concerning faith and merit associated with the Reformation, and in the political theories that found expression in the Conciliar Movement and in seventeenth-century constitutional liberalism. Although some historians have portrayed Ockham as an innovator who revolted against the traditional values and standards of medieval Christendom, it is nearer the truth to say that he was very much a product of the medieval culture and educational system, who sought to resolve problems that were generated by that culture and that had reached critical dimensions in his own time.
The condemnations of strict Aristotelianism that took place in 1277 were symptomatic of a crisis in the Scholastic effort to harmonize Greek metaphysics with the Christian creed; while the conflict between Philip the Fair and Boniface VIII, followed by the controversy between Louis of Bavaria and John XXII, brought to the surface issues concerning the sources of political and ecclesiastical authority that were becoming acute with the decline of the feudal system. It was to save the values threatened by these conflicts, rather than to destroy them, that Ockham subjected the prevailing Scholastic positions to criticism, and sought more adequate and powerful principles of analysis. His chief contributions to philosophy, lying in the areas of philosophy of language, metaphysics, and theory of knowledge, were the direct result of his effort, as a theologian, to meet the twofold commitment to reason and experience, on the one hand, and to the articles of the faith, on the other.
This dual commitment to faith and reason finds expression in two maxims that are constantly invoked in Ockham’s writings. The first is that God can bring about anything whose accomplishment does not involve a contradiction. Although this principle is accepted on the basis of the Christian creed, it is equivalent to the philosophical principle that whatever is not self-contradictory is possible, so that what is actually the case cannot be established on a priori grounds but must be ascertained by experience. The second maxim, known as Ockham’s Razor because of his frequent use of it, is the methodological principle of economy in explanation, frequently expressed in the formula “What can be accounted for by fewer assumptions is explained in vain by more.” Ockham often expressed it, however, in this longer form: “Nothing is to be assumed as evident, unless it is known per se, or is evident by experience, or is proved by the authority of Scripture” (Sentences I, d. 30, qu. 1).
These maxims are equivalent in force and constitute the unifying principle of Ockham’s doctrine, whether viewed in its theological or philosophical aspect. They determine a view of the universe as radically contingent in its being, a theory of knowledge that is thoroughly empiricist, and a rejection of all realist doctrines of common natures and necessary relations in things—all of which constitute what is called Ockham’s nominalism. They also eliminate every form of determinism in Ockham’s metaphysics and psychology, by associating the principle of divine omnipotence with that of divine liberty and freedom of choice and by making the liberty of the human will basic to moral and legal theory.
A first consequence of these principles is the elimination of various metaphysical “distinctions” that played a dominant role in late thirteenth-century Scholasticism and that derived in large measure from the interpretation of Aristotle made by the Islamic philosopher Ibn Sīnā. The real distinction between essence and existence, held to be a doctrine of St. Thomas Aquinas, supposed that in an existing thing its essence or nature, although not separable from its existence, is nevertheless really distinct from it. Ockham argued that if essence and existence are distinct realities, then it is not self-contradictory for one to exist without the other; but since it is self-contradictory to suppose that an essence exists without existence, it follows that there cannot be a real distinction between the two. By a similar argument it is shown that there cannot be a real distinction between individuals and their natures, as the theory of common natures existing in individuals supposes.
Ockham directed his main critique against the Scotist theory that the common nature differs from the individuating principle by a formal distinction that is less than a real distinction but more than a distinction of reason. To show that this involves a contradiction, Ockham argued as follows: Let the common nature be indicated by the letter a and the individuating difference by the letter b. Then, according to Duns Scotus, a is formally distinct from b. But Scotus must concede that a is not formally distinct from a. Yet, Ockham argued. wherever contradictory predicates are verified of two things, those two things must be really distinct. Hence b and a cannot be really identical if they are formally distinct, as Scotus claimed; and by the same argument it can be shown that if they are really identical, they cannot be formally distinct.
The notion of a common nature in individuals, really or formally distinct from them, is therefore self-contradictory; and it remains that universality is a property of terms, or of concepts expressed by general nouns, and is simply their capacity to be used to signify or denote many individuals. In denying that there is any universality in things, Ockham does not deny that the basis for universal predication of general terms is objectively present in individual things; he only denies that the fact that Socrates and Plato, for example, are similar in that each is a man entails that there is some entity common to both and distinct from each. Ockham’s nominalism is not to be construed as a doctrine that denies any foundation in things for the generality of terms, and his theory of human cognition rests squarely on the assumption that direct experience of existing things gives rise to concepts of universal character that directly signify things as they are or can be.
Since whatever exists is individual, Ockham holds that our knowledge of things is based on a direct and immediate awareness of what is present to our senses and intellect, which he calls intuitive cognition. He defines this type of awareness as one which enables us to form an evident judgment of contingent fact—that is, that the object apprehended exists, or that it is qualified in a certain way, or is next to another object, and so forth. Such cognition gives rise only to singular contingent propositions that are evident; hence it does not yield scientific knowledge in Aristotle’s sense, in which premises and conclusions must be of universal character. Every intuitive cognition, however, can give rise to an abstractive cognition of the same object, which Ockham defines as the cognition of an object which does not suffice for an evident judgment concerning the existence of the object or concerning a contingent fact about the object. Thus, while I am observing Socrates and hearing him talk, I can judge evidently that Socrates exists and that he is talking; but if I depart from the spot and then form the proposition that Socrates exists, or that he is talking. my statement is not evident and may in fact be false.
But Ockham insists that there is no distinction between intuitive and abstractive cognition with respect to objects cognized, but only with respect to their capacity to yield evident judgments of existence and contingent fact. In the natural course of events, every abstractive cognition presupposes an intuitive cognition of an object understood by it; but Ockham says that since the cognitions are distinct from each other and from their objects, it is logically possible for God to cause an intuitive cognition of an object which is not present or not presently existing. In such a case. Ockham says, the intuitive cognition will yield a judgment that the object is not present or that it does not exist; for it would be self-contradictory to hold that one can have an evident judgment that an object exists, if it does not exist.
The general propositions which serve as premises of scientific knowledge, in the strict sense, are established by inductive generalization from singular judgments evident by experience. But Ockham holds that such scientific statements, being formed from abstractive cognitions of their objects, cannot have absolute evidence, or necessary truth, as categorical propositions; they must be construed as necessary propositions concerning the possible, or as conditional statements. Except for premises of mathematics, which are known per se by the meanings of the terms, the principles of the natural sciences are held by Ockham to be evident by experience but not as necessary in the absolute sense, although they may be said to be necessary in the conditional sense of presupposing the common course of nature without divine interference.
Ockham’s empirical theory of knowledge and his nominalist doctrine of the relation of discourse to reality are reinforced by a remarkably original and thoroughgoing use of the logica moderna of the arts faculties, with its theory of the supposition of terms, which takes the form of a fully developed philosophy of language. Ockham’s Summa logicae gives the most complete expression to this semantically oriented logic.
Ockham’s treatment of theology is consistent with his treatment of philosophy and natural science, in the sense that absolute evidence for theological propositions cannot be had in this life and only a positive theology based on acceptance of the testimony of Christ and the saints is possible. The order established by God and revealed in the laws of the church, which Ockham ascribes to God’s potentia ordinata, is freely established by divine choice but is not necessary, since God, by his absolute power, could have ordained a different order. In moral and political philosophy Ockham applies these same criteria of divine freedom and omnipotence to refute the claims of pope and emperor alike to absolute power and dominion over members of the church or citizens of the state. The dignity of man is found in his freedom of choice; and Ockham reiterates that the law of God is a law of liberty, not to be degraded and corrupted into absolutism and coercive tyranny.
I. Original Works. Individual works include Quodlibeta septem (Paris, 1487; Strasbourg, 1491); Summa logicae (Paris-Bologna, 1498; Venice, 1508, 1522, 1591; Oxford, 1675), modern ed. of Pars prima and Pars IIa et tertiae prima, P. Boehner, ed., 2 vols. (St. Bonaventure, N.Y., 1951–1954); De sacramento altaris et De corpore christi (Strasbourg, 1491), with Quodlibeta, new ed. by T. B. Birch, with English trans., The De sacramento altaris of William of Ockham (Burlington, Iowa, 1930); Summulae in libros Physicorum (Bologna, 1494; Venice, 1506; Rome, 1637), also known as Philosophia naturalis; Super quatuor libros Sententiarum … quaestiones (Lyons, 1495), with Centiloquium theologicum, modern critical ed. of Sentences I, Prologus and Dist. I, Gedeon Gal, O.F.M., ed. (St. Bonaventure, N.Y., 1967); Expositio aurea…super artem verterem (Bologna, 1496), modern ed. of the Proemium and Expositio super librium Porphyrii, Ernest A. Moody, ed. (St. Bonaventure, N.Y., 1965); Tractatus de praedesitinatione et de praescientia Dei et de futuris contingentibus, P. Boehner, ed. (St. Bonaventure, N.Y., 1945), English trans. by Marilyn McCord Adams and Norman Kretzmann (New York, 1969); Dialogus inter magisitrum et discipulum (Lyons, 1495); and The De imperatorum et pontificum potestate of William of Ockham, C. K. Brampton, ed. (Oxford. 1927).
Collections are Guillelmi de Ockham Opera politica, vol. I, J. G. Sikes, ed. (Manchester, 1940), vol. III, H. S. Offler, ed. (Manchester, 1956), other vols. in preparation or in course of publication; and Ockham: Philosophical Writings, P. Boehner, ed. (Edinburgh, 1957), selections with English trans.
II. Secondary Literature. On Ockham and his work see Nicola Abbagnano, Guglielmo di Ockham (Lanciano, 1931); Léeon Baudry, Le Tractatus de principiis theologiae attribué à G. d’Occam (Paris, 1936); Guillaume d’Occam, I, L’homme et les oeuvers (Paris, 1950), with an excellent bibliography; and Lexique philosophique de Guillaume d’Occam (Paris, 1958); P. Boehner, Collected Articles on Ockham (St. Bonaventure, N.Y., 1956); Franz Federhofer, Die Erkenntnislehre des Wilhelm von Ockham (Munich, 1924); Martin Gottfried, Wilhelm von Ockham (Berlin, 1949); Robert Guelluy, Philosophie et théologie chez Guillaume d’Ockham (Louvain–Paris, 1947); Erich Hoch-stetter, Studien zur Metaphysik und Erkenntnislehre Wilhelms von Ockham, (Berlin, 1927); Georges de Lagarde, La naissance de l’esprit laīque au déclin du moyen áge, IV–VI (Paris, 1942–1946); Ernest A. Moody, The Logic of William of Ockham (New York-London, 1935); Simon Moser, Grundbegriffe der Naturphilosophie bei Wilhelm von Ockham (Innsbruck, 1932); Richard Scholz, Wilhelm von Ockham als politischer Denker und sein Breviloquium de principatu tyrannico (Leipzig, 1944); Herman Shapiro, Motion, Time and Place According to William Ockham (St. Bonaventure, N.Y., 1957); Cesare Vasoli, Guglielmo d’Occam (Florence, 1953), which contains a good bibliography; Paul Vignaux, Justification et prédestination au XIVe sièecle (Paris, 1934); Le nominalisme au XIVe siècle (Montreal, 1948); and “Nominalisme” and “Occam,” in Dictionnaire de théologie catholique, 15 vols. (Paris, 1903–1950), XI, cols. 733–789, 864–904; Damascene Webering, The Theory of Demonstration According to William Ockham (St. Bonaventure, N.Y., 1953); and Sytse Zuidema, De Philosophie van Occam in zijn Commentaar op de Sententien, 2 vols. (Hilversum, 1936).
Ernest A. Moody
"Ockham, William of." Complete Dictionary of Scientific Biography. . Encyclopedia.com. (May 23, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/ockham-william-0
"Ockham, William of." Complete Dictionary of Scientific Biography. . Retrieved May 23, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/ockham-william-0
Ockham, William of
OCKHAM, WILLIAM OF
b. Ockham, [later Woking], near London, England, c. 1285; d.Munich, Germany, 1347)
logic, philosophy, theology. For the original article on Ockham see DSB, vol. 10.
Ockham’s renown is due primarily to his contributions to logic and their impact on ontology, natural philosophy, and theology. He adopted a form of nominalism that is more accurately designated as conceptualism. This postscript focuses on revisions of his biography, contributions to natural philosophy, and influence.
Recent scholarship has revised Ockham’s biography on his likely residence at London before and after his period of study at Oxford, scholarly activity at Avignon, date of death and circumstances related to his death, and the location of his burial place in Munich. The completion of the Latin edition of his philosophical and theological works along with translations of several of them has contributed to a better understanding of Ockham’s relation to his predecessors and contemporaries, and of his influence on later authors. His conceptualism and account of connotative concepts continue to challenge scholars, and inform our understanding of his contribution to modern empiricism. Likewise, the projected completion of the edition of his political works will likely deepen our understanding of Ockham, making it clearer which ideas were traditional and which link him to modern liberalism.
Life Ockham entered the Franciscan order around the age of twelve as a novice probably at the London friary, and spent his early years studying the liberal arts and philosophy. In 1306 he was ordained subdeacon at South-wark, London, in the diocese of Winchester. In 1306 or 1307 he began his study of theology at Oxford, and completed the principal requirement of lecturing on the Sentences of Peter Lombard by 1319. He probably returned to London to wait for his teaching license. During the next four years he revised his commentary on the first book of the Sentences, participated in academic disputations, and wrote some of his major works on logic and natural philosophy.
Ockham’s controversial views provoked some to accuse him of heresy. The papacy summoned him to its court at Avignon in 1324. While he awaited the outcome of the investigation, he completed his last treatise on philosophical and theological questions. At the Franciscan friary where he resided, he met other Franciscans who challenged Pope John XXII’s views on evangelical poverty, the cornerstone of Franciscan spirituality. When it became clear that the pope was about to condemn even the moderate Franciscan view, Ockham fled with his associates, all of whom were excommunicated. As a result, he never received his doctorate, and eventually ended up in Munich where over the next twenty years he wrote polemical treatises against John XXII and his successors. Contrary to myth, Ockham died impenitent in 1347 probably before the Black Death reached Bavaria. He was buried in the Franciscan cemetery in Munich, which is now the site of the Bavarian National Theater. On the steps to the garage closest to the front entrance of the theater a plaque commemorates Ockham, Orlando di Lasso, and others.
The “Razor.” Aside from his extensive works on logic and relevant discussions in the Sentences commentary, he wrote several treatises on natural philosophy. Among these are a commentary on Aristotle’s Physics, a questions-commentary containing 151 questions and two shorter summaries. Although he intended to write commentaries on other organic treatises and on metaphysics, his focus on the Physics and his turn to political and moral questions diverted him from that project.
In logic his most important contributions are his so-called razor against superfluous entities and his reactions against philosophers who multiplied the number of existing things by speculating in ways that derive from inconsistencies and a careless use of language. By observing a few simple precautions, Ockham thought, such errors can be avoided. In applying his logical principles, he distinguished between absolute and connotative terms. Absolute terms are substance terms and abstract quality terms that can refer to real things. Connotative terms are concrete quality terms and terms in all of the Aristotelian categories other than substance that can refer to one real thing primarily and to another thing secondarily, but they do not signify things distinct from individual substances and inhering qualities. He applied this distinction extensively, particularly in the analysis of three of the most important topics in Aristotle’s Physics, motion, time, and place. Ockham did not deny that bodies really move, or that change takes time, or that bodies are in place and move from place to place. He treated all three as connotative terms, the result of which was the elimination of talk about them as individual things that exist independently of the things in motion, in time, and in place.
Natural Philosophy Ockham’s emphasis on eliminating superfluous entities contributed to a more empiricist and less inflationary ontology. Ockham remained an Aristotelian, however, in his acceptance of formal and material causes. He tended, though, to emphasize efficient causes over final causes in nature. Like other scholastics, he made distinctions in the analysis of place and the medium through which bodies move that imply a distinction between a description of motion and a causal analysis of motion. Contrary to Aristotle, Ockham, like Thomas Aquinas, accepted the theoretical possibility of the motion of a body through a vacuum. Because a body cannot exist in two places at the same time, its motion from one side of a postulated vacuum to the other side would require some lapse of time. This led Ockham to distinguish between the conditions of local motion and the causes of greater or lesser speed.
Ockham shared several ideas with other late medieval scholastics, but the clarity of his arguments led later authors to cite him occasionally as an inspiration. For example, several authors concluded that matter and form are not just abstract principles but really existing constituents of things. In Ockham’s version really existing physical things are composed of matter and a hierarchy of substantial forms. That doctrine along with his reduction of rarefaction and condensation to a function of the local motions of the parts of a thing inspired later authors to defend atomism. For example, Nicholas of Autrecourt, the German atomist Joachim Jungius, Kenelm Digby, and Thomas Hobbes appealed to Ockhamist doctrines in support of mechanistic analysis and atomism.
Another major consequence of Ockham’s doctrine of connotative terms is found in his analysis of mathematics. Where Aristotle prohibited transition from one genus or species to another in proofs to avoid ambiguity and thus fallacious arguments, Ockham tended to relax such prohibitions. Aristotle maintained that we should not compare circular and rectilinear motions, because the difference constitutes a specific difference, meaning that they belong to different species such that any comparison would be fallacious. Ockham’s theory of connotation, however, led him to reject Aristotle’s prohibition. In Ockham’s view circular and rectilinear do not stand for specifically different entities but express nominal definitions that can be predicated of motions in a way that permits comparison.
More generally, Ockham interpreted Aristotle as allowing for the subordination of a mathematical analysis to physical considerations, the subordination of a physical analysis to mathematical considerations, and even the partial subordination of one science to another. The consequence is that Ockham subdued the logical and ontological restrictions on mathematics, making it a suitable instrument for analyzing any problem that can be quantified or clarified logically by means of mathematics.
Even more startling was Ockham’s denial of the traditional doctrine of perceptual and cognitive species, a denial that led him to affirm action at a distance. This argument constitutes an example of Ockham’s more empiricist side. Ockham, however, followed the Aristotelian emphasis on efficient causes as deriving from potencies in things, even if his reductionistic tendencies led him to eliminate several speculatively generated entities.
Influence Ockham’s ideas influenced three philosophers at Merton College, Oxford, William Heytesbury, John Dumbleton, and Richard Swineshead, who developed a more mathematical approach that generated some interesting consequences for the mathematical description of change and motion. Among these consequences is the Merton mean-speed theorem, which provides a way of understanding the relation between a uniformly accelerated motion by comparison with a uniform motion over the same time and in the same distance. If a body moves from rest at a uniform rate of acceleration, it will cover the same distance in the same time as the same body moving uniformly at a constant velocity that is half the final velocity of the uniformly accelerated motion. It should be added, however, that medieval philosophers regarded such an analysis as useful for understanding all kinds of changes, including intension and remission of immaterial and incorporeal qualities.
Ockham’s influence on Parisian philosophers of the fourteenth century is more complex. Although his conceptualism and critique of inflationary metaphysics influenced Parisian thinkers, they tended to reject his more extreme conclusions by developing moderate interpretations consistent with high medieval scholastic Aristotelianism. For example, the views of John Buridan, Marsilius of Inghen, and Albert of Saxony tend to be more conservative. Nicole Oresme, however, shows how Ockham’s influence, even when moderated, contributed to the most original and challenging analysis of nature in the fourteenth century. Like Ockham, Oresme characterized terms such as motion as connotative. Oresme’s view was not as reductive as Ockham’s but he too followed Ockham’s critique in applying mathematics to problems of change and variation. He did not deny that motion is a real thing altogether, but affirmed it only as a mode of being. He denied the material or corporeal reality of species and their reality in the sensible world, allowing them only a spatial-temporal reference and thus rendering them intelligible in purely mathematical terms.
The influence of these ideas on later authors is difficult to trace. In general, they inspired more mechanistic thinking or greater emphasis by Aristotelians on mathematical analysis, but most historians consider Galileo Galilei’s innovations as surpassing by far the achievements of his predecessors and contemporaries.
WORKS BY OCKHAM
Opera Politica. 3 vols. Manchester, U.K.: Manchester University, 1940–1974.
Opera Philosophica et Theologica. 17 vols. St. Bonaventure, NY: Franciscan Institute, 1967–1988.
“William of Ockham’s Commentary on Porphyry.” Translated by Eike-Henner W. Kluge. Franciscan Studies 33 (1973): 171–254, and 34 (1974): 306–382. Translation of Expositio in libros artis logicae, prooemium et expositio in librum Porphyrii de Praedicabilibus, Opera Philosophica 2, 3–131.
Ockham’s Theory of Terms. Translated by Michael Loux. Notre Dame, IN: University of Notre Dame, 1974. Translation of Summa Logicae, Part 1, Opera Philosophica 1, 3–238.
Ockham’s Theory of Propositions. Translated by Alfred Freddoso and Henry Schuurman. Notre Dame, IN: University of Notre Dame, 1980. Translation of Summa Logicae, Part 2, Opera Philosophica 1, 239–356.
Ockham on Aristotle’s Physics. Translated by Julian Davies. St. Bonaventure, NY: Franciscan Institute, 1989. Translation of Brevis summa libri Physicorum, Opera Philosophica 6, 2–134.
Philosophical Writings: A Selection. Translated by Philotheus Boehner, revised by Stephen Brown. Indianapolis, IN: Hackett, 1990.
Quodlibetal Questions. 2 vols. Translated by Francis Kelley and Alfred Freddoso. New Haven, CT: Yale University, 1991. Translation of Quodlibeta Septem, Opera Theologica 9.
Opera Politica. Vol 4. Auctores Britannici Medii Aevi, Vol. 14. Oxford: Oxford University, 1997. The political works were edited by Hilary S. Offler, the last volume posthumously by a committee chaired by David Luscombe. John Kilcullen, George Knysh, Volker Leppin, John Scott, and Jan Ballweg are editing Ockham’s Dialogus for the British Academy. Drafts are available from http://www.britac.ac.uk/pubs/dialogus/ockdial.html.
Demonstration and Scientific Knowledge in William of Ockham. Translated by John Longeway. Notre Dame, IN: University of Notre Dame, 2007. Translation of Summa Logicae, Part 3, section 2, Opera Philosophica 1, pp. 503–584. The introduction characterizes Ockham as “the founder of European empiricism.”
Adams, Marilyn. William Ockham. 2 vols. 2nd ed. Notre Dame, IN: University of Notre Dame, 1989. The most comprehensive study in English.
Beckmann, Jan. Ockham-Bibliographie 1900–1999. Hamburg, Germany: Felix Meiner, 1992.
Boehner, Philotheus. Collected Ariticles on Ockham. Edited by Eligius Buytaert. St. Bonaventure, NY: Franciscan Institute, 1958. Fundamental articles by Ockham’s earliest twentieth-century editor.
Brown, Stephen. “A Modern Prologue to Ockham’s Natural Philosophy.” Sprache und Erkenntnis im Mittelalter, Miscellanea Mediaevalia 13, no. 1 (1981): 107–129. The most authoritative expert on Ockham’s physical treatises.
Courtenay, William. “Ockham, Chatton, and the London Studium: Observations on Recent Changes in Ockham’s Biography.” In Die Gegenwart Ockhams, edited by Wilhelm Vossenkuhl, Rolf Schönberger, and Otl Aicher, 327–337. Weinheim, Germany: VCH-Verlagsgesellschaft, 1990.
Etzkorn, Girard. “Ockham at Avignon: His Response to Critics.” Franciscan Studies 59 (2001): 9–19. The latest revision of Ockham’s biography.
Franciscan Studies. Commemorative Issues, Vols. 44 and 45, Annual 22–23, 1984–1985. Collection of papers from the celebration at the Franciscan Institute in 1985 of the seventh centenary of Ockham’s birth and of the completion of the critical edition. Volume 44 was predated to 1984.
Gál, Gedeon. “William of Ockham Died ‘Impenitent’ in April 1347.” Franciscan Studies 42 (1982): 90–95. Gál directed the modern critical edition of Ockham’s philosophical and theological works.
Goddu, André. The Physics of William of Ockham. Leiden, Netherlands: E.J. Brill, 1984.
_____. William of Ockham’s Arguments for Action at a Distance.” Franciscan Studies 44 (1984): 227–244.
_____. William of Ockham’s ‘Empiricism’ and Constructive Empiricism.” In Die Gegenwart Ockhams, edited by Wilhelm Vossenkuhl, Rolf Schönberger, and Otl Aicher, 208–231. Weinheim, Germany: VCH-Verlagsgesellschaft, 1990.
_____. Connotative Concepts and Mathematics in Ockham’s Natural Philosophy.” Vivarium 31 (1993): 106–139.
_____. Ockham’s Philosophy of Nature.” In The Cambridge Companion to Ockham, edited by Paul Spade, 143–167. Cambridge, U.K.: Cambridge University Press, 1999.
_____. The Impact of Ockham’s Reading of the Physics on the Mertonians and Parisian Terminists.” Early Science and Medicine 6 (2001): 204–237.
Karger, Elizabeth. “Ockham’s Misunderstood Theory of Intuitive and Abstractive Cognition.” In The Cambridge Companion to Ockham, edited by Paul Spade, 204–226. Cambridge, U.K.: Cambridge University Press, 1999. The clearest analysis of Ockham’s theory.
Lang, Helen. Aristotle’s Physics and its Medieval Varieties. Albany: State University of New York, 1992. Indispensable evaluation of medieval interpretations of Aristotle.
Livesey, Steven. “William of Ockham, the Subalternate Sciences, and Aristotle’s Prohibition of metabasis.” British Journal for the History of Science 18 (1985): 127–145. Groundbreaking study.
Maurer, Armand. The Philosophy of William of Ockham in the Light of Its Principles. Toronto: Pontifical Institute of Mediaeval Studies, 1999. This is the most accessible book-length study in English.
Miethke, Jürgen. Ockhams Weg zur Sozialphilosophie. Berlin: Walter de Gruyter, 1969. The most comprehensive study of Ockham in any language.
Moody, Ernest. The Logic of William of Ockham. Reprinted. New York: Russell and Russell, 1965.
_____. Ockham and Aegidius of Rome.” In Studies in Medieval Philosophy, Science, and Logic, edited by Ernest Moody, 161–188. Berkeley: University of California, 1975. The most influential article on Ockham’s account of motion through a void.
Murdoch, John. “Scientia mediantibus vocibus: Metalinguistic Analysis in Late Medieval Natural Philosophy.” Sprache und Erkenntnis im Mittelalter, Miscellanea Mediaevalia 13, no. 1 (1981): 73–106. The best analysis of the logical context of fourteenth-century natural philosophy.
Panaccio, Claude. “Semantics and Mental Language.” In The Cambridge Companion to Ockham, edited by Paul Spade, 53–75. Cambridge, U.K.: Cambridge University Press, 1999. Best brief study of Ockham’s conceptualism and doctrine of connotative terms.
Spade, Paul. “Ockham’s Distinctions between Absolute and Connotative Terms.” Vivarium 13 (1975): 55–76. Reprinted in Lies, Language and Logic in the Late Middle Ages, by Paul Spade. London: Variorum Reprints, 1988. Foundational article challenging the coherence and completeness of Ockham’s account.
—_____. Lies, Language and Logic in the Late Middle Ages. London: Variorum Reprints, 1988.
_____. Three Versions of Ockham’s Reductionist Program.” Franciscan Studies 56 (1998): 335–346.
_____. —, ed. The Cambridge Companion to Ockham. Cambridge, U.K.: Cambridge University Press, 1999. Now standard collection of articles in English.
"Ockham, William of." Complete Dictionary of Scientific Biography. . Encyclopedia.com. (May 23, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/ockham-william
"Ockham, William of." Complete Dictionary of Scientific Biography. . Retrieved May 23, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/ockham-william
William of Ockham
William of Ockham
The English philosopher and theologian William of Ockham (ca. 1284-1347) was the most important intellectual figure in the 14th century and one of the major figures in the history of philosophy.
The first half of the 14th century was one of the most active, creative periods in medieval thought. Building on the solid foundation of the 13th-century achievements in science, logic, metaphysics, and epistemology, William of Ockham and his immediate followers developed an approach to philosophy and theology that became known as nominalism. This school of thought, alongside the humanist movement, aided in the transition from the medieval to the modern world.
William was born in the village of Ockham in Surrey. Having received his early education in Latin grammar and the liberal arts, possibly at the nearby monastic house of Augustinian canons at Newark, he joined the Franciscan order and studied arts and philosophy at their convent in London. In February 1306 he was ordained a subdeacon at the church of St. Saviour at Southwark in London, where Southwark Cathedral now stands. The following fall Ockham began his 13 years of theological study at Oxford.
During the years 1317 to 1320 Ockham lectured on the Sentences of Peter Lombard, the standard theological textbook from the 12th to the 16th centuries. After the completion of his theological studies, he became lecturer at the Franciscan convent in Reading, where he taught off and on until 1324. There he revised the first book of his commentary on the Sentences, lectured on logic and Aristotle's Physics, and engaged in quodlibetic disputes with other theologians.
In these various works Ockham set forth ideas which, within 20 years, earned him an international reputation and placed him alongside Thomas Aquinas and John Duns Scotus as one of the most significant minds of the age. Like Thomas and Scotus, the different areas of Ockham's thought are closely interrelated and marked by distinctive features that give his thought a special character. Ockham's ideas should not, however, be seen as a rejection or destruction of 13th century thought. He borrowed from the past and perfected constructive tendencies already present in the previous period.
Epistemology and Empiricism
The 13th-century tendency to base scientific knowledge, knowledge of the physical world, on sense experience was accepted and extended by Ockham. In place of the Aristotelian description of how man comes to know (a description that sees the human mind primarily as a passive receptacle that abstracts the universal form or concept from particular things that are experienced and transmitted through a multistage process), Ockham described the mind as an active agent that knows the particular immediately and directly through intuitive cognition. Intuitive cognition is the direct apprehension by the mind of a particular, existing thing according to which the mind forms a judgment that such a thing exists and apprehends those facts contingent upon its existence, such as size, shape, color, and so on. In addition to intuitive cognition, which is the initial and primary means of knowledge, there is abstractive cognition, closely related to memory, which can reflect on an object but does not convey any knowledge of whether the object presently exists.
This direct apprehension of the existing particular thing by means of intuitive cognition increased the empirical quality of medieval thought at the expense of the Platonic reliance on forms or ideas. It also meant that man initially and primarily knows the particular, and only on the basis of that and similar experiences does he begin to form a more general concept known as the universal.
It is because of Ockham's rejection of the "realistic" interpretation of the universal or general concept that the term "nominalist" is applied to him. Ockham rejected the idea that there is similarity among things of the same species because there exists a "common nature," prior to existing individual things, which inheres in the latter and makes them similar. While recognizing similarities among things in nature, Ockham saw that similarity as the result of a generic relationship that does not endanger the peculiar individuality of each object. The concept is formed when several individuals of the same species are considered at the same time, and when one forms a composite in the mind of those features they have in common. One of the results of this approach, with its stress on the priority and importance of knowledge of the particular, was to give added impulse to the scientific tradition of the 13th and 14th centuries by stressing both empiricism and an inductive method.
Theology and Ethics
By restricting the objects of scientific knowledge to those individuals known directly through sense experience and by rejecting the idea of a common nature prior to and inherent in the things experienced, Ockham limited the kind of things man could know by reason apart from revelation, and he thus changed the character of metaphysical discussion. In much the same way, Ockham limited the number of truths in theology that can be established by reason alone, thus making theological propositions depend much more on revelation and the teaching of the Church than would be true for earlier scholastic theologians from Anselm to Aquinas. Most "truths" of natural theology are, for Ockham, learned by way of revelation.
Because most theological propositions are known only through revelation, this does not make them any the less certain for Ockham, who saw certainty as the result of different types of evidence. Scientific knowledge produces a certainty based on belief in the way man's mind operates and in the validity of human sense experience. For Ockham this form of knowledge is so compelling that it is impossible not to acknowledge its certainty. The certainty of theological knowledge is based on belief that what God has revealed through Scripture and the Church cannot be in error. Such "knowledge" is compelling only for the Christian and is not of the same order as scientific knowledge.
The overriding conception of Ockham's theology is the freedom and omnipotence of God, an idea that shapes much of his philosophy as well. The realm of God's choice is limited only by the principle of contradiction, namely, that God cannot do that which is logically impossible. Since God wills from eternity and not within time, the choices made by God have become the reliable principles upon which the human world depends. The uniformity in nature which Ockham continually asserted is basically a uniformity in God's will, which can never be arbitrary because it is one with His intellect and wisdom. By His initial choices God has freely bound Himself to act in reliable, definable ways, both within the physical world and within the Church.
The contingency of the universe and the theological order upon the will of God includes the ethical system according to which God rewards and punishes. Good deeds are defined by their conformity to God's revealed law, and although God retains his freedom to reject as meritorious those good deeds done in a state of grace, he has in fact committed himself to accept them as meritorious of eternal life.
In 1324 Ockham was called to Avignon to answer charges of heretical doctrine in his writings. Two lists of suspect opinions were drawn up, but neither resulted in a formal condemnation.
While living in Avignon near the papal court awaiting the results of the investigation, Ockham wrote a defense of his theories on the Eucharist, which was one of the major areas of his thought under attack. In addition, at the urging of the head of the Franciscan order, Michael of Cesena, Ockham undertook a study of the concept of apostolic poverty, a concept basic to the Franciscan ideal and one under attack by Pope John XXII. When in 1328, Ockham came to the conclusion that John XXII was incorrect on the issue of apostolic poverty and perhaps even heretical—and when it appeared that the Pope was about to deliver a pronouncement on the issue that would make the Franciscan position appear heretical—Ockham, Cesena, and several others fled Avignon on the night of May 26 toward Italy, and they sought and received the protection of John's major enemy, Emperor Louis of Bavaria.
The remainder of Ockham's life was spent at the Franciscan convent in Munich, where he wrote political treatises against the positions of John XXII and his successors. In these treatises Ockham argued that Scripture and the established theological tradition of the Church are the two sources for authority in doctrine. Neither the papacy nor secular political powers have the authority to proclaim doctrines that go against Scripture or tradition. Ockham agreed with Marsilius of Padua that Christ did not establish the papacy, and one can find in Ockham a strong defense of the authority of a general Church council. However, unlike Marsilius, Ockham believed that the pope did possess administrative authority within the Church, and as long as he did not fall into heresy he should not have his administrative or judicial power questioned.
The best introduction in English to Ockham's thought is The Collected Articles on Ockham (1958) by Philotheus Böehner, who, more than anyone else, was responsible for the revised understanding of Ockham. Particular aspects of Ockham's thought are examined in Ernest A. Moody, The Logic of William of Ockham (1935); Damascene Webering, The Theory of Demonstration according to William Ockham (1953); and Herman Shapiro, Motion, Time and Place according to William Ockham (1957). For background see Philotheus Böehner, Medieval Logic: An Outline of Its Development from 1250 to c. 1400 (1952); Gordon Leff, Medieval Thought: St. Augustine to Ockham (1958) and Paris and Oxford Universities in the 13th and 14th Centuries (1968); David Knowles, The Evolution of Medieval Thought (1962); and Arthur Hyman and James J. Walsh, eds., Philosophy in the Middle Ages: The Christian, Islamic and Jewish Traditions (1967).
Adams, Marilyn McCord, William Ockham, Notre Dame, Ind.: University of Notre Dame Press, 1987. □
"William of Ockham." Encyclopedia of World Biography. . Encyclopedia.com. (May 23, 2017). http://www.encyclopedia.com/history/encyclopedias-almanacs-transcripts-and-maps/william-ockham
"William of Ockham." Encyclopedia of World Biography. . Retrieved May 23, 2017 from Encyclopedia.com: http://www.encyclopedia.com/history/encyclopedias-almanacs-transcripts-and-maps/william-ockham
Ockham, William Of
Ockham, William Of
William of Ockham, political theorist and philosopher of science, was born about 1280, probably at Ockham, a village in the county of Surrey, near London. He entered the Franciscan order, studying and lecturing at Oxford University from about 1309 to 1323. In 1324 he was summoned to Avignon by Pope John XXII to answer charges of having expounded heretical doctrines. It appears, however, that the commission appointed to investigate the charges against him reached no final agreement concerning the heretical character of his teachings.
Ockham was still in detention in Avignon in 1327, the year that Michael of Cesena, the general of the Franciscan order, arrived there to answer for his attacks upon the papal position on evangelical poverty. Ockham became involved in the issue, siding with his general against the pope. In May 1328, evidently fearing the worst, Ockham, along with Michael and several others, fled for protection to the court of the pope’s political enemy, Louis of Bavaria, and the pope promptly excommunicated them. Ockham retaliated with the pen: during the next twenty-odd years he directed a series of bitter polemics at successive popes and their exalted claims of power.
With the death of Louis of Bavaria in 1347, Ockham’s position became hopeless, and he appears to have taken steps to reconcile himself with the church. A formula of submission was drawn up, but it is not known whether Ockham actually signed it. He died in Munich about 1349, probably a victim of the Black Death.
Political thought. Despite their polemical tone, Ockham’s political writings are essentially conservative in outlook. In general he favored moderate opinions in regard to the hotly contested political issues of his time. He appears to have been interested not in political theory as such but rather in the special problem of the relation between church and state. Ultimately, his position, which remained rooted in the traditionally established separation between the two powers, contributed little to the solution of the knotty problem of precise definition.
Specifically, Ockham maintained that the spiritual power is autonomous because of its divine origin. Within its own realm it retains absolute independence, subject only to divine law. Neither the emperor, then, nor any other representative of the secular arm, has the right to interfere in church affairs, except in the instance of some evident breach of divine law—as, for example, when a heretic occupies the papal seat.
Similarly, the secular power is derived from God through the consent of the people. It too retains absolute autonomy within its proper sphere, subject only to natural law. Neither the church, then, nor the people, can divest the emperor of his power, except in the instance of an evident breach of natural law—as, for example, when he proves dangerous to the general welfare.
Philosophy of science. Ockham was enormously influential in shaping and giving impetus to the empirical trend which came to dominate thought in the late Middle Ages. Science, for Ockham, consists in a body of statements about natural entities and occasions. In all cases, the ultimate ground for the truth of a stated fact is the actual being of the things about which the fact is true. The scientific proposition, that is, is itself related to matters of physical fact as sign is to significatum; hence, it is objective circumstance alone that lends verity to a scientific statement. Truth, then, and falsity, when predicated of a proposition, mean that there obtains or does not obtain agreement between the proposition as formulated and the fact as given.
Clearly, in the light of the possibility of empirical verification as thus envisioned by Ockham, there is a great disparity between such statements as “Socrates is walking” and “Time is composed of instants.” In the former case, verification is relatively simple. In the latter, however, verification is not so simple: where and how does one seek out and encounter “time”? How does one demonstrate that its structural components are “instants”? Still, if Ockham’s notion of the relation obtaining between truth, scientific assertion, and empirical fact is to avoid a breakdown, such verification must, in some way, be possible. It was with this problem in mind that Ockham noted the distinction between absolute terms (nomina absoluta) and connotative terms (nomina connotativa).
Absolute terms, for Ockham, have real definitions, while connotative terms are nominally defined. Thus, when the elements entering into the definition of a term signify only the individual entities for which the defined term can stand, the term is absolute. When, on the other hand, the elements entering into the definition of a term do not all signify the same individual entities for which the definiens is a sign, the term is connotative.
As Ockham saw it, the physical universe admits of but two varieties of actual existent: substance and quality. Hence, there are but two kinds of absolute terms: terms properly ascribed to the category of substance (concrete absolute terms) and terms properly ordered under the category of quality (abstract absolute terms). Neither class of actual existent, however, is ever experienced in abstraction from contingent circumstance. Substances, that is, are never apprehended per se apart from their accidental determinations, any more than qualities are ever experienced apart from change; and since the written, spoken, or conceived expression of these contingent circumstances is invariably couched in connotative terms, it is the connotative term which is first in the order of “coming-to-know.” But all such terms, according to Ockham, are susceptible of resolution into functions of absolute terms.
The significance of the distinction and ultimate relationship between absolute and connotative terms for Ockham’s theory of empirical verification is quite clear. Unless there is some way of exhibiting connotative terms as functions of absolute terms whose significata, in turn, can be sought out and confronted in the physical realm of substances and qualities, definition as well as demonstration would involve circularity, or infinite regress, and the possibility of empirical verification of scientific statements as conceived by Ockham would be vitiated.
In sum, Ockham’s approach provides the philosophic basis for the formulation of two regulative questions to which he would submit all physical descriptions, laws, and hypotheses: (1) What do the terms that we use in these physical explanations actually mean? and (2) How can we be assured of the truth of that which is asserted? In the last analysis, Ockham allowed as meaningful only those assertions that are reducible to statements whose elements designate observable entities, and as true only those that are satisfied by an existing state of affairs.
[Other relevant material may be found inScientific Explanation.]
Guillelmi de Ockham opera politica. Vols. 1-3. Edited by J. G. Sikes et al. Manchester (England) Univ. Press, 1940-1963. -→ The first three volumes of the critical edition of Ockham’s political writings.
Gulielmi Ockham opera omnia philosophica et theologica.Volume 1: Expositionis in libros artis logicae prooemium et expositio in librum Porphyrii de praedicabilibus. Edited by E. A. Moody. St. Bonaventure, N.Y. Franciscan Institute, 1965. -→ The first volume of a critical edition of Ockham’s nonpolitical writings.
Philosophical Writings. Edited and translated by Philotheus Boehner. New York and London: Nelson, 1957.
Summa logicae. Edited by Philotheus Boehner. St. Bonaventure, N.Y.: Franciscan Institute, 1951-1954. -→Parts 1 and 2 have been published to date.
Baudry, LÉon 1949 Guillaume d’Occam: Sa vie, ses oeuvres, ses idees sociales et politiques. Paris: Vrin. -→ A good source on Ockham’s life and works, and a bibliography of publications about him.
Jacob, Ernest F. (1943) 1963 Essays in the Conciliar Epoch. 2d ed., rev. Univ. of Notre Dame (Ind.) Press.→ See especially Chapter 5, pages 85-105 on “Ockham as a Political Thinker.”
Moody, Ernest A. (1935) 1965 The Logic of William of Ockham. New York: Russell. → The best single work on Ockham’s logic and methodology.
Morrall, John B. 1949 Some Notes on a Recent Interpretation of William of Ockham’s Political Philosophy. Franciscan Studies 9:335-369.
Shapiro, HermanL. 1957 Motion, Time and Place According to William Ockham. St. Bonaventure, N.Y.:Franciscan Institute. → A study of Ockham’s philosophy of science.
"Ockham, William Of." International Encyclopedia of the Social Sciences. . Encyclopedia.com. (May 23, 2017). http://www.encyclopedia.com/social-sciences/applied-and-social-sciences-magazines/ockham-william
"Ockham, William Of." International Encyclopedia of the Social Sciences. . Retrieved May 23, 2017 from Encyclopedia.com: http://www.encyclopedia.com/social-sciences/applied-and-social-sciences-magazines/ockham-william
William of Ockham
"William of Ockham." The Concise Oxford Dictionary of World Religions. . Encyclopedia.com. (May 23, 2017). http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/william-ockham
"William of Ockham." The Concise Oxford Dictionary of World Religions. . Retrieved May 23, 2017 from Encyclopedia.com: http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/william-ockham
Ockham, William of
William of Ockham: see William of Occam.
"Ockham, William of." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (May 23, 2017). http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/ockham-william
"Ockham, William of." The Columbia Encyclopedia, 6th ed.. . Retrieved May 23, 2017 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/ockham-william