Speaker: Zach Weber (University of Otago)

Title: “Non-classical logic and inconsistent mathematics”

Date, Time and Venue: Monday, 1 April 2019, 14:00-15:00, 260-6115 [Business School Building, Level 6]

Abstract: Faced with logical paradoxes like the liar and the sorites, there are several options, including classical and non-classical (paracomplete and paraconsistent) approaches. I will briefly review some costs and benefits of each. Then I will mainly focus on the paraconsistent approach, using logics that allow for some contradictions. I will outline how paraconsistent logic may be applied in the foundations of mathematics, especially in naive set theory. I’ll conclude with a brief discussion of the wider inconsistent mathematics program as it stands today.

Everyone welcome!

Speaker: Patrick Girard (University of Auckland)

Title: “Mini-Series on Paradoxes”

Date, Time and Venue: Monday, [to start with] 11 and 25 March 2019, 14:00-15:00, 260-6115 [Business School Building, Level 6]

Abstract: Patrick will offer 2-3 seminars on paradoxes. He will start with historical/conceptual paradoxes (about God, being bald, and there being no change). He will then talk about modern logical paradoxes that involve truth, set membership and conditionals. He will end with paradoxes involving probability. The journey will take you from a conceptual/historical understanding of paradoxes in philosophy, go via problems in mathematics and logic, and end with more specific paradoxes behind the kind of mathematics that CMSS members are using in social choice theory and the like.

Everyone welcome!