Information, Possible Worlds and the Cooptation of Sceptism

Abstract

The article investigates the sceptical challenge from an information-theoretic perspective. Its main goal is to articulate and defend the view that either informational scepticism is radical, but then it is epistemologically innocuous because redundant; or it is moderate, but then epistemologically beneficial because useful. In order to pursue this cooptation strategy, the article is divided into seven sections. Section 1 sets up the problem. Section 2 introduces Borel numbers as a convenient way to refer uniformly to (the data that individuate) different possible worlds. Section 3 adopts the Hamming distance between Borel numbers as a metric to calculate the distance between possible worlds. In Sects. 4 and 5, radical and moderate informational scepticism are analysed using Borel numbers and Hamming distances, and shown to be either harmless (extreme form) or actually fruitful (moderate form). Section 6 further clarifies the approach by replying to some potential objections. In the conclusion, the Peircean nature of the overall approach is briefly discussed.

Keywords: Borel numbers, Hamming distance, Informational scepticism, David Lewis, Levenshtein distance, Modal metrics, Philosophy of information, Possible worlds, Scepticism, Semantic information