|noumenon (ˈnuːmɪnən, ˈnaʊ-)|
|—n , pl -na|
|1.||Compare phenomenon See also thing-in-itself (in the philosophy of Kant) a thing as it is in itself, not perceived or interpreted, incapable of being known, but only inferred from the nature of experience|
|2.||the object of a purely intellectual intuition|
|[C18: via German from Greek: thing being thought of, from noein to think, perceive; related to nous mind]|
in the philosophy of Immanuel Kant, the thing-in-itself (das Ding an sich) as opposed to what Kant called the phenomenon-the thing as it appears to an observer. Though the noumenal holds the contents of the intelligible world, Kant claimed that man's speculative reason can only know phenomena and can never penetrate to the noumenon. Man, however, is not altogether excluded from the noumenal because practical reason-i.e., the capacity for acting as a moral agent-makes no sense unless a noumenal world is postulated in which freedom, God, and immortality abide.
Learn more about noumenon with a free trial on Britannica.com.