Paul Feyerabend is one of major philosophers who have criticized scientific method. He shows some of the important scientific events don’t follow any of presenting methods by philosophers of science. But it is interesting that he uses a special method in your argument that is a redductio ad absurdum method. Also he recommended another method-anthropological method -for studying science. In this article, first we consider the redductio ad absurdum method in his arguments and then explain anthropological method