The purpose of this note is to explore in a preliminary way some of the basic properties and implications of a concept which may be of use in dealing with "classes" of the type cited above. The concept in question is that of a fuzzy
set, that is, a "class" with a continuum of grades of membership. As will be seen in the sequel, the notion of
a fuzzy set provides a convenient point of departure for the construction of a con- ceptual framework which parallels
in many respects the framework used in the case of ordinary sets, but is more general than the latter and, potentially,
may prove to have a much wider scope of applicability, particularly in the fields of pattern classification and information
proc- essing. Essentially, such a framework provides a natural way of dealing with problems in which the source
of imprecision is the absence of sharply defined criteria of class membership rather than the presence of random
variables.