Cratylus

Greek philosopher of the late fifth century B.C. Cratylus was a student of Heraclitus and drew extreme relativist conclusions from his master's teachings on the universal flux of things. In particular, he denied that phenomena have any qualitative fixity; hence, either one can say nothing about ongoing phenomena or one can say anything at all. Heraclitus taught that one cannot step into the same river twice; Cratylus, that one cannot step into it even once. He believed that one can only point things out, not make assertions about them.