Speaker: Tai-Wei Hu (University of Bristol)
Date and Time: Friday, March 21st 2025, 12:30-14:00
Venue: ILLC Seminar Room F1.15, Science Park 107 and online.
Title: Logic of Reciprocal Empathy: Shallow Interpersonal Reasoning and Latent Infinity.
Abstract. We present the logic RELβ of reciprocal empathy with a cognitive bound β, in order to study human thought and behavior in society. Reciprocal empathy means that one puts himself into the other’s situation, including the other’s empathization back to himself. The logic RELβ is a fixed-point extension of epistemic logic KD with perception operators. In RELβ, interpersonal (and intrapersonal) epistemic depths are bounded by β < ω. Yet, the logic RELβ is shown to be sound and complete with respect to the standard Kripke semantics for KD but with the restriction of permissible formulae. Our aim is to study the syntactical logic RELβ, and Kripke semantics is needed for a full study. With respect to interpersonal depths, our framework has some subtlety with infinity or unboundedness, which we call latent infinity. We study how latent infinity is hidden. We apply RELβ to an example of communication and coordination due to David Lewis. It is given as a formal theory within RELβ. This shows that our approach has large potential for studies of societal problems.