講演者: Dr. Kohei Kishida (Dalhousie University)
日時: 2019年7月10日(水) 16:30-18:00
Relevance and Reduction in Aristotle’s Logic
Aristotle is often called the founder of logic, for inventing his categorical logic or “syllogistic”. Interpretations diverge as to the logical nature of syllogistic, however. In some accounts, Aristotle gives an axiomatic science of categories that uses propositional or even quantifier logic; he is then a user of logic, but hardly the founder.
My talk, in contrast, reconstructs Aristotle’s syllogistic as a self-sufficient logic on its own. While several commentators propose this line of reconstruction, many of them characterize good syllogisms as valid syllogisms. This characterization, however, strips syllogistic of its power as a “logic of science” that Aristotle uses to organize scientific knowledge. The goal of my talk is to give a reconstruction of Aristotle’s syllogistic that identifies the property that good syllogisms have beyond mere validity, by tracing the theoretical structure of Aristotle’s systematization. It will be shown that the property in question is a specific sense of relevance, and that Aristotle’s notion of “reduction” plays a more substantial role than commentators understand in formally achieving the sense of relevance.