Open Peer Review on Qeios Moral Vagueness: Does Mathematics Have a Practical Solution? Sergei Korchevoi Funding: No specific funding was received for this work. Potential competing interests: No potential competing interests to declare. Abstract If one favors Moral Intuitivism in order to deal with Skeptical argument, then thinking by analogy with mathematical knowledge is of use. A major objection to the mathematical analogy in Moral epistemology is the threat of moral relativism in practical applications of moral pluralism if we employ mathematical pluralism as a vector to proceed. Thus, the advocacy for moral pluralism faces an obstacle which should be addressed: a problem of moral «vague» predicates. This article addresses moral vagueness and considers objections toward several treatments of related Sorties series through possibility of deepening a proper mathematical intuition. However, the issue of human moral competency cannot be erased from the picture. It is a critical question for morality which very likely falls beyond the scope of Moral epistemology. Keywords: Moral epistemology, vagueness, vague predicate, repression, mass repressions. Preliminary remarks: acknowledgement of biases I have been thinking about the problem of vague predicates in moral epistemology for several years. One could encounter a persistent question over the last ten years in Russian media: are we already living in «1937»? In other words, can we agree that political repressions in Russia have reached their climax somewhat equivalent to Stalin's repressions? For a moral epistemologist, the question may be reformulated in terms of Sorties paradox (Hyde and Raffman, 2018). Is the «heap» of murders, unlawful prosecutions, and terror big enough to call it a really big «heap» of mass repressions? The decision to put my thoughts on paper was triggered by an interview, a conversation between a well known, very successful contemporary Russian writer Chihartishvily (aka Boris Akunin) and an independent journalist Osetinskaia (RussiansAreOkay, 2024). Both interlocutors are quite intelligent and have an ambition to dig deep into social and political matters. There was just a couple of minutes in the interview that caught my attention. The interviewer, Osetinskaia, presented the above question related to «1937». As a result, both of the interlocutors expressed their irritation by the cowardice of Russian «folk» because «merely» about a thousand of political prisoners are behind the bars at the moment. Qeios, CC-BY 4.0 · Article, April 15, 2024 Qeios ID: P1E4VY · https://doi.org/10.32388/P1E4VY 1/11