'Young', 'tall' or 'happy' are all examples of vague meanings, but fuzzy logic focuses only on vague predicates that are measurable. 'Youth' and 'height' are measurable, but not 'happiness' (at least not in the same way). A measurable vague predicate P can be represented by a curve...
i.e., the compatibility of 0 with the predicate ‘small number’ is 1 or, in an alternative way, the possibility of calling 0 a ‘small number’ is 1, …, and so on. Vague properties, unlike crisp ones, are not an all or nothing matter. There is no universal definition of ‘young...