Soft Computing and Its Applications, Volume One

268 Soft Computing and Its Applications

synthetic language. For example, “Age’’ is a linguistic variable when its values

are assumed to be “young,’’ “old,’’ “very young,’’ “not very old,’’ and so forth.

• In two-valued logical systems, a proposition p may be qualified, by associating

with p a truth value, either “true’’ or “false’’; a modal operator such as “pos-

sible’’ or “necessary’’; and an intentional operator such as “know’’ or “believe.’’

Fuzzy logic has three principal modes of qualication:

• Truth-qualification, for example, (Mary is young) is not quite true, in which the

qualified proposition is (Mary is young) and the qualifying truth ...