The twelfth century saw the flourishing of competing and self-consciously different schools of liberal arts, mainly dialectic and logic, probably all based in Paris, a city which underwent at the time a period of very rapid growth. This multiplication can be explained by a historical process, which Richard Southern called the deinstitutionalization of the schola, that is, the fact that teaching became detached from the corporate schools of the past and attached to an individual master who taught wherever he could find a place to teach. While cathedral schools only admitted one master, in Paris it was possible to buy a licentia docenti by paying a fee to the cathedral authorities and to open a school and settle as a master. These masters received money from their students in response to a new and growing interest of students who sought new skills and knowledge which traditional institutional schools were, by their nature and function, not well adapted to provide. The success of this new type of teaching was such that, according to Southern, there were at least 25 well-known schools within a hundred miles of Paris. These schools, also called sectae, were of various size and nature.
With Peter Abelard’s The Story of My Misfortunes and John of Salisbury’s Metalogicon, we have kept two lively descriptions of the twelfth-century schools.
These various schools produced introductions to logic, logical treatises, and commentaries, for example,
To the Categories, to Aristotle’s De interpretatione, or to
Porphyry’s Isagoge.
The main ones are the following:
1. The Nominales. This is the name given to the followers of Peter Abelard. A good testimony of the work done in this school was the Summa dialectice artis of William of Lucca, a thinker who was also very open to the ideas of Gilbert of Poitiers. Nominalism about universals (genera and species are vocabula or voces) is an important thesis of the school; however, the teaching of the school went further, covering theses such as, topical loci are not required (apti) for syllogisms; one may not infer a negative claim from an affirmative.
2. The Porretani. Gilbert of Poitiers had a posterity and influence unequalled in the twelfth century. He had disciples and enthusiastic defenders of his theological thought. An excellent testimony of the reflection produced by the Porretan movement is the Compendium logicae porretanum. This text develops one of the main lines of Porretan ontology, ontological particularism, according to which everything which exists is particular. This position rejects universals as shared entities, since the Porretan doctrine states that no entity can exist simultaneously in two spatiotemporally distinct individuals: ‘‘nihil quod sit in uno est in alio’’ (Compendium logicae porretanum, III.15). The Compendium retains the thesis according to which being comes from the form; however, contrarily to what the realists defend, the same form cannot be common to Plato and Socrates. Therefore, according to this text, there are as many humanities as there are men (quot homines, tot humanitates).
3. The Parvipontani (so called because they gathered at the Petit Pont in Paris) or Adamitae were the followers of Adam of Balsham, sometimes also called Adam of the Petit Pont, the author of a treatise called Art of Discussing (Ars disserendi), which demonstrates an innovative approach to logic. The second part of the only surviving copy of this text is indeed not Adam’s own work, but that of members of his school.
4. The Meludinenses or Robertini: the disciples of Robert of Melun. The most interesting literary production of this current is the Ars meliduna, a text from the 1170s/ 1180s. The Ars meliduna contains an original theory of universals, some elements of which are Stoic in origin. Universals exist, and belong to a realm of their own, different from that of concrete beings. They are outside sensible things and are understood outside them; they are participated by many sensible things (a pluribus participabilis). They are not substances or properties and they can only be grasped by the intellect.
5. The Albricani or Montani: the disciples of Alberic (de Monte) in a school on the Mont Sainte Genevieve. A good testimony of the work of this school is provided by a text that discusses the traditional points of the teaching of logic: the Introductiones montanae maiores.
The most interesting case is that of the Porretani. On the basis of the thought of a master - Gilbert of Poitiers - we see the constitution of a real current of thought, composed both of people who were deeply influenced by his thought (the most noticeable example being no doubt Alan of Lille who, in the years 1160-1180, both in his Summa Quoniam homines and in his Rules of Theology, makes extensive use of Gilbert’s ontology and philosophy; Simon of Tournai can also be mentioned), and of people who took to heart to defend his theology against accusations of heresy (Hugh of Honau’s quest for references to Patristic authorities, in particular from Hugh Etherian, in order to defend Gilbert’s theological positions is characteristic; the result of this work can be found, among other places, in his treatise De homoysion et homoeysion and in his Liber de diversitate naturae et personae). The years during which Gilbert taught in Paris (1137-1142) were probably decisive in the formation of his ‘‘school.’’ Gilbert’s influence can be found both in logic and in theology, in works as diverse as the Summa Zwettlensis (written before 1150, maybe by Peter of Vienna), the Tractatus invisibilia Dei for the theological aspect, and for the years 1150-1170, in the Compendium logicae porretanum, the Glosulae porretane super Priscianum minorem, the Commentarium in Categorias Aristotelis for the logical and semantical aspect. Gilbert’s influence is still perceptible in the last years of the twelfth century, as shown by a remarkable text, the Dialogus Ratii et Everardi, written by the Porretan Cistercian Everard of Ypres.
World History
