(...) According to Hegel, if I begin with a clear opposition like the difference between being and nothing, I soon discover that the opposition is not as clear as it appears. Without its relationship to nothing that is evident in becoming, pure being is indistinguishable from pure nothing. Being requires nothing in order to be. Contradiction is the name for the necessary impurity of every identity - its inability to just be itself.
Identity is incapable of being identity without introducing some form of otherness that reveals the lack of perfect self-identity. The failure of what Hegel calls formal thinking lies in its inability to account for the necessity of contradiction. As Hegel puts it in the Science of Logic, "The firm principle that formal thinking lays down for itself ... is that contradiction cannot be thought. But in fact the thought of contradiction is the essential moment of the concept. Formal thought does in fact think it, only it at once looks away from it." Even formal thinking that believes itself to be free of contradiction must go through contradiction in order to perform its operations. Its formulations of identity necessarily involve the negation of this same identity, but formal thinking holds this negation as external and separate from the identity. As a result, contradiction remains repressed within formal thinking. Hegel's philosophy is the return of this repressed.