Volume 68, Issue 4, 2020
Evolution-Creationism: An Open Debate
, Krzysztof Krawczyk
, Rafał Palczewski
Knowability as De Re Modality
A Certain Solution to Fitch Paradox
In the paper, we try to find a new, intuitive solution to the Fitch paradox. We claim that traditional expression of Knowability Principle (p → ◊Kp) is based on erroneous understanding of knowability as de dicto modality. Instead, we propose to understand knowability as de re modality. In the paper we present the minimal logic of knowability in which Knowability Principle is valid, but Fitch Paradox does not hold anymore. We characterize the logic semantically as well as by an axiomatic and tableaux procedure approach.