ON the Derrida's Overturn of the Logo centrism

The logo centrism that rules the western philosophical field for more than two thousand years is questioned by many scholars spontaneously in contemporary time.Derrida,the founder of the deconstruction sharply criticize the logo centrism with the principle of deconstruction.Through the Plato's concept to praise speech and devalue writing system,he subverts the graded system that speech is the center and writing language is the edge and points out that speech and writing are both the external forms of human's mind.And he further makes clear that writing system is the record and archive of the speech and speech is the supplement and substitution of the writing,and thus these two are depended on each other.