 The medieval tradition of logic is generally thought to have begun with Boethius (c. 475–526), who ambitiously tried to preserve philosophical learning from the declining culture of late antiquity. In fact, however, he was only able to save parts of ancient logic, primarily Aristotelian logic (see Lee 1984 for a discussion of Aristotle’s syllogistic in late ancient thought). He wrote extensively on the theory of the syllogism, producing a Latin translation of the Prior Analytics, though it was not used very much before the twelfth century (see Aristotle, Analytica Priora, and the introduction by Minio-Paluello). He also wrote two textbooks on the categorical syllogism: On the Categorical Syllogism (De syllogismo categorico) and Introduction to Categorical Syllogisms (Introductio ad syllogismos categoricos) (for the texts, see Migne 1847 and Thomsen Thörnqvist 2008). In addition, he produced an interesting book called On Hypothetical Syllogisms (De hypotheticis syllogismis), which will be touched on in the discussion below (see Boethius [Obertello 1969] for the text). 