GILBERT DE LA PORREE (Gilbertus Porretanus or Pictaviensis), an eminent scholastic logician and theologian of the 12th century, was born at Poitiers. He was educated under Bernard de Chartres and Auselm of Lion, and after completing his studies remained attached as teacher to the church at Chartres. In 1135 he is recorded as discharging these functions, but he seems soon after to have repaired to Paris and opened public courses on dialectics and theology. His fame caused him to be called to his native town, where in 1141 he was elected bishop. The heterodox opinions he was led to express regarding the doctrine of the Trinity drew upon his works the condemnation of the church. Thc synod of Rheims in 1148 procured papal sanction for four propositions opposed to certain tenets of Gilbert's, and the works of the latter were condemned until they should be corrected in accordance with the principles of the church. Gilbert seems to have submitted quietly to this judgment ; he yielded assent to the four propositions, and remained on friendly terms with his antagonists till his death in 1154. Gilbert is almost the solitary logician of the 12th century who is quoted by the greater scholastics of the succeeding age. His chief logical work, the treatise De Sea. Principi was regarded with a reverence almost equal to that given to Aristotle, and furnished matter for numerous commentaries. Albertus Magnus did not disdain to commtnt upon this work of an earlier logician. The treatise itself is an elaborate discussion of the Aristotelian categories, specially of the six subordinate modes. Gilbert distinguishes in the ten categories two classes, one essential, the other derivative. Essential or inhering (f)rnict inhwrentes) in the objects themselves are only substance, quantity, quality, and relation in the stricter sense of that term. The remaining six, when, where, action, passion, position, and habit, are relative and subordinate (forma? assistenies). This suggestion has wine interest, but it cannot be said to have great value, either in logic or in the theory of knowledge. More important in the history of scholasticism are the theological consequences to which Gilbert's realism led him. In the commentary on the treatise De Trinitate, erroneonsly supposed to be by Boetius, he proceeds from the metaphysical notion that pure or abstract being is prior in nature to that which is. This pure being is God, and must be distinguished from the triune God as known to us. God is incomprehensible, and,the categories cannot be applied to determine his existence. In God there is no distinction or difference, whereas in all substances or things there is duality, arising front the element of matter. Between pure being and substances stand the ideas or forms, which subsist though they are not substances. These forms, when materialized, are called formw substantiates or natirty ; they are the essences of things, and in themselves have no relation to the accidents of things. Things are temporal, the ideas perpetual, God eternal. The pure form of existence, that by which God is God, must be distinguished from the three persons who are God by participation in this form. The form or essence is one, the persons or substances three. It was this distinction between Deitas or Divinitas and Deus that led to the condemnation of Gilbert's doctrine.

See Ritter, Gesela. d. Phil., vii. 437-74: Ifriur6au, Phil. Seelastique, 2i1 ed., i. 447-78 ; StkW, Phil. d. 272-88.