{ "id": "1601.04168", "version": "v1", "published": "2016-01-16T14:25:24.000Z", "updated": "2016-01-16T14:25:24.000Z", "title": "On the strength of a weak variant of the Axiom of Counting", "authors": [ "Zachiri McKenzie" ], "comment": "14 pages", "categories": [ "math.LO" ], "abstract": "In this paper $\\mathrm{NFU}^{-\\mathrm{AC}}$ is used to denote Ronald Jensen's modification of Quine's `New Foundations' Set Theory ($\\mathrm{NF}$) fortified with a type-level pairing function but without the Axiom of Choice. The axiom $\\mathrm{AxCount}_\\geq$ is the variant of the Axiom of Counting which asserts that no finite set is smaller than its own set of singletons. This paper shows that $\\mathrm{NFU}^{-\\mathrm{AC}}+\\mathrm{AxCount}_\\geq$ proves the consistency of the Simple Theory of Types with Infinity ($\\mathrm{TSTI}$). This result implies that $\\mathrm{NF}+\\mathrm{AxCount}_\\geq$ proves that consistency of $\\mathrm{TSTI}$, and that $\\mathrm{NFU}^{-\\mathrm{AC}}+\\mathrm{AxCount}_\\geq$ proves the consistency of $\\mathrm{NFU}^{-\\mathrm{AC}}$.", "revisions": [ { "version": "v1", "updated": "2016-01-16T14:25:24.000Z" } ], "analyses": { "keywords": [ "weak variant", "denote ronald jensens modification", "consistency", "simple theory", "result implies" ], "note": { "typesetting": "TeX", "pages": 14, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2016arXiv160104168M" } } }