noumenon(redirected from Thing in itself)
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noumenon(no͞o`mənŏn'), in the philosophical system of Immanuel KantKant, Immanuel
, 1724–1804, German metaphysician, one of the greatest figures in philosophy, b. Königsberg (now Kaliningrad, Russia). Early Life and Works
..... Click the link for more information. , a "thing-in-itself"; it is opposed to phenomenonphenomenon,
an observable fact or event; in philosophy the definitions and uses of the term have varied. In the philosophy of Aristotle phenomena were the objects of the senses (e.g., sights and sounds), as opposed to the real objects understood by the mind.
..... Click the link for more information. , the thing that appears to us. Noumena are the basic realities behind all sensory experience. According to Kant, they are not knowable because they cannot be perceived, but they must be thinkable because moral decision making and scientific investigation cannot proceed without the assumption that they exist.
a term widely used in medieval and modern philosophy to signify something that can be perceived by the mind, unlike the phenomenon, which is given in experience and is perceived through the senses.