  There is, indeed, an extensive literature of medieval commentaries on the Posterior Analytics, and much of this literature is very important; we find in it a great deal of material on the authors’ attitudes to necessity, the structure of science, the relation between various sciences, the autonomy of philosophy vis-à-vis theology, and the like. However, it cannot be taken to be automatically relevant to the practice of reasoning in the Middle Ages: the logical metatheory (that of the syllogism) is far too restrictive, and the conditions placed on scientific demonstrations are far too stringent, for it to be a plausible description of very many actual processes of reasoning, in the Middle Ages or at any other time.