This occurred to me this morning as I was contemplating the differences between the formalist, algebraic, and categorial schools of mathematical reasoning for an encyclopaedia article. Whereas Boolean logic is certainly the logic of sets, Aristotelian logic, especially the syllogisms Barbara and Celarent, would seem to be more that of *-autonomous categories. LOGICIANS AS PEACENIKS: The Early Days Alexander lived a hearty life of dames and kings, While his tutor Aristotle nattered on of names and things. But while Alexander's military followed him to wars, Aristotle's syllogisms followed from his laws. Darius and Alexander fought a mighty war. The likes of such an argument had not been seen before. But by Barbara and Celarent did Aristotle swear As the mistresses of argument that never hurt a hair. Vaughan Pratt, 4/10/06