Speaker:
Torben Braüner 

Title: 
Second-order false-belief reasoning: Some modal-logical analyses

Abstract:
A number of researchers apply logical modelling to problems from cognitive psychology. Our work on Theory of Mind belongs to this tradition, and is distinguished by (1) its use of hybrid modal logic, which takes local shifts of perspectives as fundamental (2) its focus on second-order reasoning about mental states.

The literature on first-order false belief is extensive, but less is known about the second-order case. We analyze the first-order case by combining belief formation sequencing with perspectival reasoning, and lift this analysis to the second-order level by adding a recursive belief manipulation rule. Technically, the second-order formalization is obtained by embedding Braüner’s first-order formalization (Conference on Theoretical Aspects of Rationality and Knowledge 2013, Journal of Logic, Language and Information 2014, Annual Conference of the Cognitive Science Society 2015) into a higher-level proof which leaves the original layer of reasoning unchanged.

We argue that our formalization supports an existing position on the development of second-order reasoning, the “conceptual-change” position. Accordingly, second-order mastery is a fundamental cognitive achievement that requires new conceptual apparatus, not merely increased information processing capacity. The application of the belief manipulation rule suggests that second-order reasoning involves a richer understanding of belief that reflects a conceptual shift.

This is joint work with Patrick Blackburn and Irina Polyanskaya.