In [[philosophy]], a '''noumenon''' ({{IPAc-en|ˈ|n|uː|m|ə|n|ɒ|n}}, {{IPAc-en|ˈ|n|aʊ|-}}; {{ety|grc|νoούμενον}}; {{small|[[plural]] form}}: '''noumena''') is knowledge<ref>{{cite book | chapter-url=https://plato.stanford.edu/search/r?entry=/entries/formal-epistemology/&page=1&total_hits=1035&pagesize=10&archive=None&rank=7&query=Epistemology | title=The Stanford Encyclopedia of Philosophy | chapter=Formal Epistemology | year=2021 | publisher=Metaphysics Research Lab, Stanford University }}</ref> posited as an [[Object (philosophy)|object]] that exists independently of human [[sense]].<ref>{{cite web|quote=1. intellectual conception of a thing as it is in itself, not as it is known through perception; 2. The of-itself-unknown and unknowable rational object, or thing-in-itself, which is distinguished from the phenomenon through which it is apprehended by the physical senses, and by which it is interpreted and understood; – so used in the philosophy of Kant and his followers.|url=http://www.websters-dictionary-online.org/definitions/Noumenon|archive-url=https://web.archive.org/web/20110928115535/http://www.websters-dictionary-online.org/definitions/Noumenon?cx=partner-pub-0939450753529744:v0qd01-tdlq&cof=FORID:9&ie=UTF-8&q=Noumenon&sa=Search|archive-date=2011-09-28|url-status=dead|title=Noumenon | Definition of Noumenon by Webster's Online Dictionary|access-date=2015-09-10}}</ref> The term ''noumenon'' is generally used in contrast with, or in relation to, the term ''[[Phenomena (philosophy)|phenomenon]]'', which refers to any [[Object (philosophy)|object]] of the senses. [[Immanuel Kant]] first developed the notion of the noumenon as part of his [[transcendental idealism]], suggesting that while we know the noumenal world to exist because human [[sensibility]] is merely receptive, it is not itself sensible and must therefore remain otherwise [[Epistemology|unknowable]] to us.<ref>{{Cite encyclopedia|url=https://www.britannica.com/topic/noumenon|title=noumenon {{!}} philosophy|encyclopedia=Encyclopedia Britannica|access-date=2017-09-04|language=en}}</ref> In [[Kantianism|Kantian philosophy]], the noumenon is often associated with the unknowable "[[thing-in-itself]]" ({{lang-de|Ding an sich}}). However, the nature of the relationship between the two is not made explicit in Kant's work, and remains a subject of debate among Kant scholars as a result.
