Ma`rifat Falsafi

From the viewpoint of Muslim logicians and philosophers the Principle of "impossibility of contradiction has a high position among parts of the knowledge system and forms the foundation of all logical and nonlogical knowledge in a way it secures a position similar to that of necessary being compared with possible beings. Regarding other knowlegdes being based upon this principle there are five theories: Some has declared all knowledges as results of the principle of impossibility of contradiction; some has known some priori principles and common sense principles as exceptions to the principle of impossibility of contradiction; some explained the knowleges as being based upon the principle of impossibility of contradiction for double certainty and negation of its oppossite or rejection of other knowledges; and yet some has said that the dependence upon this principle ia a kind of secoudary and a for need knowlege about knowledge.