Adaptive Fuzzy Systems
Bart Kosko · 1991
Fuzziness is multivaluedness. Truth, set membership, and subset containment take on degrees in [0, 1] instead of taking on only the limiting bivalent extremes in {0, 1}. The degrees in [0, 1] define fuzzy units, or fits. Statements are true to some degree. An element belongs to, or fits in, a fuzzy set to some degree. One fuzzy set contains another fuzzy set to some degree.