Summa

Summa and its diminutive summula (plural summae and summulae, respectively) are mainly used, in English and other modern languages, for texts that 'sum up' knowledge in a field, such as the compendiums of theology, philosophy and canon law which were used both as textbooks in the schools and as books of reference during the Middle Ages.

Some historians of theology cite Origen's peri archon as the first summary of Catholic theology. Others consider that the first in point of time is "De Trinitate" by St. Hilary of Poitiers. The distinction has also been accorded to Radulfus Ardens, an eleventh-century theologian and preacher, a native of Beaulieu, author of a comprehensive "Speculum Universale", still in Manuscript. In this wide sense of the word, however, the encyclopedic treatises of St. Isidore of Seville, Rabanus Maurus etc., entitled "De Etymologiis" or "De Universo" might also be considered to be summaries of theology and philosophy.

In the stricter sense of the word, "Summa" is applied to the more technical systematic compendiums which began to appear in the twelfth century. According to the Stanford Encyclopedia of Philosophy, the form was invented by the grammarian Peter Helias. An alternative title is "Sentences" (Latin Libri Sententiarum), the diminutive, "Summulæ", being of later origin. What is peculiar to "summists" or "sententiaries", as the authors of these works are called, is the adoption of the method first suggested by Gerbert in his "De Rationali et Ratione Uti", and used by Abelard in his "Sic et Non", consisting in an exposition of contradictory views, the affirmative and negative. Progress towards the final form of the thirteenth-century "Summæ" is marked by the greater care which was taken, as time went on, to explain in a systematic manner the apparent contradiction among the conflicting opinions presented. Besides this method of exposition, the twelfth-century summists adopted dialectic definitely as a means of elucidating, not only philosophical, but also theological truth. Finally the summists adopted more or less unanimously a fixed division of the field of theology and philosophy, and adhered more or less closely to a definite order of topics. Here, of course, there was room for individual preferences in the matter of arrangement and sequence of problems, as we see when we compare with one another the "Summæ" even of the latest period of Scholasticism.

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