Fuzziness and Internal Category Structure

Abstract

There is a growing recognition, exemplified in some of the research on prototype theories, that natural cognitive categories may have complex internal structures. With the advent of fuzzy set theory, the prospect of defining and measuring structural properties of categories has become more tempting than in the past. Fuzziness is the most obvious such property, although as the material in section 4.1 reveals, this concept turns out to be appropriately slippery. Given Kochen’s (1975) findings that approximately half his sample treated graded categories in an essentially unfuzzy way, and given the perennial behavioral scientific concern with whether a trait is best thought of as discrete or continuous, a reasonable measure of fuzziness may be quite useful.