摘要
First,we give the notion of set under the figure(ordinary set)and its operative lows,Second,it is proved that system(I^2,∧，∨.,)of fuzzy sets is isomorphic with the system(u(X);∩，∪，c)of sets under the figure.Therefore we can denote fuzzy set and fuzzy relation by ordinary sets.Thus one showed new thought and new method to study deeply fuzzy set and fuzzy relation.
