              More importantly, the unvarnished condition of Aristotle’s surviving treatises does not hamper our ability to come to grips with their philosophical content. His thirty-one surviving works (that is, those contained in the “Corpus Aristotelicum” of our medieval manuscripts that are judged to be authentic) all contain recognizably Aristotelian doctrine; and most of these contain theses whose basic purport is clear, even where matters of detail and nuance are subject to exegetical controversy. 