From Perception to Belief and Back Again-A Formal Epistemology of Perception

• Applicant: Professor Dr. Peter Brössel
• Subject Area: Theoretical Philosophy
• Term: since 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 325247545

It is a longstanding philosophical idea that we form our perceptual beliefs on the basis of perceptual experiences and that a perceptual belief can be justified by reference to the corresponding perceptual experience. This procedure corresponds to the first step of rational, or justified, belief acquisition. In a second step, we use these perceptual beliefs to justify all our other a posteriori beliefs. Concerning the second step, traditional and formal epistemology and philosophy of science have progressed considerably in showing how we proceed rationally from observational data to theories about the world. Concerning the first step, some progress has been achieved in traditional epistemology and philosophy of perception. However, in formal philosophy virtually no progress has been made concerning the first step. Only very recently have philosophers started to make progress in this area, most of whom are working at the intersection of formal epistemology, philosophy of mind and of cognition. It is here where the project takes its starting point. The overarching aim of the project From Perception to Belief and Back Again is to investigate in detail the first step of rational belief acquisition and, thus, to focus on justificatory relation(s) between perceptual experiences and perceptual belief, and between their contents, respectively. The project thereby approaches this aim by combining a formal epistemology perspective with a philosophy of cognition perspective, to obtain what I refer to as a formal epistemology of perception. For this purpose, the project combines extremely successful formal tools from formal epistemology and philosophy of cognition: probability theory - to model rational reasoning - and the Conceptual Space framework by Gärdenfors - to model the content of perceptual experience and conceptual thought. Based on this combined framework we can develop a theory of rational reasoning from the non-conceptual content of perceptual experience to the conceptual content of belief and a theory of concept learning from perceptual experience alone.

• DFG Programme: Independent Junior Research Groups