OCCAM, WILLIAM OF (d. c. 1349), English schoolman, known as Doctor invincibilis and Venerabilis inceptor, was born in the village of Ockham, Surrey, towards the end of the 13th century. Unattested tradition says that the Franciscans persuaded him while yet a boy to enter their order, sent him to Merton College, Oxford (see G. C. Brodrick, Memorials of Merton College, p. 194), and to Paris, where he was first the pupil, afterwards the successful rival, of Duns Scotus. He probably left France about 1314, and there are obscure traces of his presence in Germany, in Italy, and in England during the following seven years. It has generally been held that in 1322 he appeared as the provincial of England at the celebrated assembly of the Franciscan order at Perugia, and that there he headed the revolt of the Franciscans against Pope John XXII.; but, according to Little (English Historical Review, vi. 747), the provincial minister on this occasion was William of Not tingham. Probably, however, Occam was present at the assembly. His share in this revolt resulted in his imprisonment, on the charge of heresy, for seventeen weeks in the dungeons of the papal palace at Avignon. He and his companions - Michael of Cesena, general of the order, and Bonagratiamanaged to escape, and found their way to Munich, where they aided Louis IV. or V. (q.v.) of Bavaria in his long contest with the papal curia. It was for Occam's share in this controversy that he was best known in his lifetime. Michael of Cesena died in 1342, and Occam, who had received from him the official seal of the order, was recognized as general by his party. The date of his death and the place of his burial are both uncertain. He probably died at Munich in 1349.
William of Occam was the most prominent intellectual leader in an age which witnessed the disintegration of the old scholastic realism, the rise of the theological scepticism of the later middle ages, the great contest between pope and emperor which laid the foundations of modern theories of government, and the quarrel between the Roman curia and the Franciscans which showed the long-concealed antagonism between the theories of Hildebrand and Francis of Assisi; and he shared in all these movements.
The common account of his philosophical position, that he reintroduced nominalism, which had been in decadence since the days of Roscellinus and Abelard, by teaching that universals were only flatus vocis, is scarcely correct. The expression is nowhere found in his writings. He revived nominalism by collecting and uniting isolated opinions upon the meaning of universals into a compact system, and popularized his views by associating them with the logical principles which were in his day commonly taught in the universities, He linked the doctrines of nominalism on to the principles of the logic of Psellus, which had been introduced into the West in the Summulae of Peter of Spain, and made them intelligible to common understandings. The fundamental principles of his system (see Scholasticism) are that "Essentia non sunt multiplicanda praeter necessitatem" ("Occam's Razor"), that nouns, like algebraical symbols, are merely denotative terms whose meaning is conventionally agreed upon (suppositio), and that the destructive effect of these principles in theological matters does not in any way destroy faith (see the Centilogium Theologicum, Lyons, 1495, and Tractatus de Sacramento Altaris).
In the Opus nonaginta dierum (1330) (written in reply to John XXII.'s libellus against Michael of Cesena), and in its successors, the Tractatus de dogmatibus Johannis XXII. papae (1333-1334), the Compendium errorum Johannis XXII. papae (1335-1338) and in the Defensorium contra errores Johannis XXII. papae (1335-1339), Occam only incidentally expounds his views as a publicist; the books are mainly, some of them entirely, theological, but they served the purpose of the emperor and of his party, because they cut at the root of the spiritual as well as of the temporal supremacy of the pope. In his writing Super potestate summi pontificis octo quaestionum decisions (1339-1342) Occam attacks the temporal supremacy of the pope, insists on the independence of kingly authority, which he maintains is as much an ordinance of. God as is spiritual rule, and discusses what is meant by the state. His views on the independence of civil rule were even more decidedly expressed in the Tractatus de jurisdictione imperatoris in causis matrimonialibus, in which, in spite of the medieval idea that matrimony is a sacrament, he demands that it belongs to the civil power to decide cases of affinity and to state the prohibited degrees. By 1343 there was in circulation his great work the Dialogus (see Goldast ii. 398-957), in which he attempted to present his views in a complete summary. It consists of three parts. The first is the De fautoribus hereticorum, and deals with the pope as arbiter in the matter of heresy. The second part is the refutation of the doctrines of John XXII. (see above treatises). The third was to be in nine sections, of which the first and second sections alone remain to us. It is probable that the Opus nonaginta dierum and the Compendium errorum were intended to form part of the work. His last work, De Electione Caroli IV., restates his opinions upon temporal authority and adds little that is new.
In all his writings against Pope John XXII. (q.v.), Occam inveighs against the pope's opinions and decisions on the value of the life of poverty. The Compendium errorum selects four papal constitutions which involved a declaration against evangelical poverty, and insists that they are full of heresy. Occam was a sincere Franciscan, and believed with his master that salvation was won through rigid imitation of Jesus in His poverty and obedience, and up to his days it had always been possible for Franciscans to follow the rules of their founder within his order.' John XXII., however, condemned the doctrine and excommunicated its supporters, some of whom were so convinced of the necessity of evangelical poverty for a truly Christian life that they denounced the pope when he refused them leave to practise it as Antichrist. After Occam's days the opinions of Francis prevailed in many quarters, but the genuine Franciscans had no place within the church. They were Fraticelli, Beghards, Lollards or other confraternities unrecognized by the church and in steady opposition to her government.
Beside the theological and political works above quoted, Occam wrote Summa Logices (Paris, 1488, Oxford, 1675) commentaries on Porphyry's Isagoge, on the Categoriae, De Interpretatione and Elenchi of Aristotle. These latter were printed in 1496 at Bologna, and entitled Expositio Aurea super totam artemveterem; Quaestiones in quattuor libros sententiarum (Lyons, 1495).
There is no good monograph on Occam. For an account of his logic, see Prantl, Geschichte der Logik (1855-1870); for his philosophy, see Stockl, Geschichte der Philosophie des Mittelalters (1864-1866), vol. ii., for his publicist writings, see Riezler, Die literarischen Widersacher der Piipste zur Zeit Ludwig des Baiers (1874). See also T. M Lindsay's article on "Occam and his connexion with the Reformation," in the Brit. Quart. Review (July, 1872). Among ancient documents consult Denifle and Chatelain's Chartularium Universitatis Parisiensis, vol. ii. pt. i. (Paris, 1887); Wadding's Annales Minorum (ed. Fonseca, vols. 7 and 8, Rome, 1733). For a list of Occam's works, see Little's Grey Friars, pp. 225-234.
(T. M. L.)