In most knowledge-based systems, the expertsu27 uncertainty is described by a real number from the interval [0,1] (this number is called subjective probability, degree of certainty, etc.). However, experts usually use a small finite set of words to describe their degree of unecratinty; thus, to adequately describe the expertu27s optinion, it is desirable to use a finite (granular) logic. If all we know about the expertu27s opinion on two statements A and B is this expertu27s degrees of certainty d(A) and d(B) in these two statements, and the user asks a query u22A and B?u22, then we need to estimate the degree d(A and B) based on the given values d(A) and d(B). In this paper, we formalize the natural demand that gradual changes in d(A) and d(B) must lead to gradual changes in our estimate for d(A and B) (we called it continuity). We show that the only continuous u22andu22-operation is min(a,b). Likewise, the only continuous u22oru22-operation is max(a,b), the only continuous u22notu22-operation corresponds to f(a)=1-a, etc
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