From The Art and Popular Culture Encyclopedia
The noumenon is a posited object or event that is known (if at all) without the use of the senses. The term is generally used in contrast with, or in relation to "phenomenon", which refers to anything that appears to, or is an object of, the senses. In Platonic philosophy, the noumenal realm was equated with the world of ideas known to the philosophical mind, in contrast to the phenomenal realm, which was equated with the world of sensory reality, known to the uneducated mind. Much of modern philosophy has generally been skeptical of the possibility of knowledge independent of the senses, and Immanuel Kant gave this point of view its classical version, saying that the noumenal world may exist, but it is completely unknowable to humans. In Kantian philosophy the unknowable noumenon is often linked to the unknowable "thing-in-itself" (Ding an sich, which could also be rendered as "thing-as-such" or "thing per se"), although how to characterize the nature of the relationship is a question yet open to some controversy.
The Greek word noumenon (νοούμενoν), plural noumena (νοούμενα), is the middle-passive present participle of νοεῖν (noein), "I think, I mean", which in turn originates from the word "nous" (from νόος, νοῦς, perception, understanding, mind). A rough equivalent in English would be "something that is thought", or "the object of an act of thought".
"But it was just this difference between abstract knowledge and knowledge of perception, entirely overlooked by Kant, which the ancient philosophers denoted by noumena and phenomena. (See Sextus Empiricus, Outlines of Pyrrhonism, Book I, Chapter 13, ' What is thought (noumena) is opposed to what appears or is perceived (phenomena).' ) This contrast and utter disproportion greatly occupied these philosophers in the philosophemes of the Eleatics, in Plato's doctrine of the Ideas, in the dialectic of the Megarics, and later the scholastics in the dispute between nominalism and realism, whose seed, so late in developing, was already contained in the opposite mental tendencies of Plato and Aristotle. But Kant who, in an unwarrantable manner, entirely neglected the thing for the expression of which those words phenomena and noumena had already been taken, now takes possession of the words, as if they were still unclaimed, in order to denote by them his things-in-themselves and his phenomena."
The Noumenon's original meaning of "that which is thought" is not compatible with the "thing–in–itself", which signifies things as they exist apart from being images in the mind of an observer.
- Schopenhauer's criticism of the Kantian philosophy
- Transcendental idealism
- The Void (philosophy)