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iconic symbol

a linguistic sign (written or spoken word) that has a physical resemblance, rather than an arbitrary relation, to its referent. Examples include onomatopoeic coinages, such as choo-choo (train), and the signs used in pictographic languages. With these few exceptions, linguistic signs are held to be arbitrary in most modern thinking on language. The contrary view, which holds that there is a general if hidden correspondence between the sounds of words and their referents, is known as the theory of phonetic symbolism. Compare arbitrary symbol.

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Psychology term of the day

January 30th 2025

Gödel’s proof

Gödel’s proof

a proof that in any logic system at least as powerful as arithmetic it is possible to state theorems that can be proved to be neither true nor false, using only the proof rules of that system. Published in 1931, this incompleteness result was very challenging to the mathematics of the time. British mathematician Alan Turing (1912–1954), with his proof of the undecidability of the halting problem, extended this result to computation (see Turing machine). [Kurt Gödel (1906–1978), Austrian-born U.S. mathematician]