Webin summary, fitch’s paradox of knowability gets us into a twisty problem about truth and knowledge. On one hand, we have the hopeful idea that all truths are possible to know. This isn’t just a puzzle on paper. Webthe paradox states that this assumption implies the omniscience principle, which asserts that every truth is known. Essentially, fitch's paradox asserts that the existence of an unknown truth is unknowable. So if all truths were knowable, it would follow that all truths are in fact known. Webclarification to protein folding problem: Enigma, paradox, solution biophys rev. 2023 apr 4;15 (2):161. Alexei v finkelstein 1 2 3 , natalya s bogatyreva 1 , dmitry n ivankov 4 , sergiy o garbuzynskiy 1. The paradox of knowability threatens to draw a logical equivalence between the believable claim that all truths are knowable and the obviously false claim that all truths are known. In this paper we evaluate the leading proposals. Webin this review, we discuss the key ideas and discoveries leading to the current understanding of protein folding kinetics, including folding landscapes and funnels, free energy barriers at the folding/unfolding pathways, and the solution of levinthal’s paradox. Webin this paper, we propose a logic of unknowable truths, investigate the logical properties of unknown truths and unknowable truths, which includes the similarities of the two notions and the relationship between the two notions, and axiomatize this logic. Download conference paper pdf. Webthe main objection raised by the realists to the ‘epistemic’ conceptions of truth is the paradox of knowability, an argument for the conclusion that there are unknowable truths. Webwe will discuss in this review the key ideas and discoveries leading to the current understanding of folding kinetics, including the solution of levinthal’s paradox, as well as the current state of the art in the prediction of protein folding times.