<philosophy of science, logic> an informal method for solving problems in the absence of an algorithm for formal proof. Heuristics typically have only restricted applicability and limited likelihood of success but, as George Polya showed, contribute significantly to our understanding of mathematical truths. Recommended Reading: George Polya, How to Solve It (Princeton, 1971); Gerd Gigerenzer amd Peter M. Todd, Simple Heuristics That Make Us Smart (Oxford, 1999); and George Polya, Mathematics and Plausible Reasoning (Princeton, 1990).
[A Dictionary of Philosophical Terms and Names]
1. <PI> A rule of thumb, simplification or educated guess that reduces or limits the search for solutions in domains that are difficult and poorly understood. Unlike algorithms, heuristics do not guarantee optimal, or even feasible, solutions and are often used with no theoretical guarantee.
[What is a "feasible solution"?]
2. <algorithm> approximation algorithm.
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