Graham Priest: The catuṣkoṭi, the saptabhaṇgī, and 'non-classical' logic

SNEEPA talk series 2020/21 Speaker: Graham Priest Title: The catuṣkoṭi, the saptabhaṇgī, and 'non-classical' logic Abstract: The Principles of Excluded Middle and Non-Contradiction are highly orthodox in Western philosophy. They are much less so in Indian philosophy. Indeed there are logical/metaphysical positions that clearly violate them. One of these is the Buddhist catuṣkoṭi; another is the Jain saptabhaṇgī. Contemporary Western logicians have, however, investigated systems of “non-classical” logic in which these principles fail, and some of these bear important relationships to the catuṣkoṭi and the saptabhaṇgī. In this talk, I we look at these two principles, and see how these may inform and be informed by those systems.