The Problem of Logical Omniscience: An Alternative to Non-normal Worlds

Authors

  • Mateusz Klonowski Nicolaus Copernicus University, Toruń
  • Krzysztof Krawczyk Nicolaus Copernicus University, Toruń

DOI:

https://doi.org/10.14394/filnau.2019.0002

Keywords:

epistemic logic, modal logic, Rantala models, non-normal possible worlds, Łoś operator, moderately rational agent, problem of logical omniscience

Abstract

In this paper, we bring up the problem of logical omniscience in epistemic logic. One way of avoiding the problem is through Rantala models, where non-normal worlds are introduced. Such models are vulnerable to criticism, as we show. One of many issues that occur is the Bjerring result, which states that incorporating non-normal worlds makes the agent logically incompetent. For this reason, we propose a different solution based on positional logics.

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Published

2019-03-31

How to Cite

Klonowski, M., & Krawczyk, K. (2019). The Problem of Logical Omniscience: An Alternative to Non-normal Worlds. The Philosophy of Science, 27(1), 27–48. https://doi.org/10.14394/filnau.2019.0002