<philosophy of science> a color-predicate used by Goodman to illustrate a significant problem with inductive predictions. With respect to a designated future time, an object is grue if it is seen to be green when first observed before that time or if it is seen to be blue when first observed after that time. The problem is that our present observations of green grass seem to provide equal support for hypotheses that grass is green and that grass is grue (or gred, for that matter). There is no simple and apparent way of forestalling this gruesome difficulty. Recommended Reading: Nelson Goodman, Fact, Fiction, and Forecast (Harvard, 1954) and Grue!: The New Riddle of Induction, ed. by Douglas Stalker (Open Court, 1994).
[A Dictionary of Philosophical Terms and Names]
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