wicked problems

The concept of "wicked problems" was originally proposed by Horst Rittel (a pioneering theorist of design and planning, and late professor at the University of California, Berkeley) and M. Webber in a seminal treatise for social planning. Rittel expounded on the nature of ill-defined design and planning problems which he termed "wicked" (ie. messy, circular, aggressive) to contrast against the relatively "tame" problems of mathematics, chess, or puzzle solving.
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