Hegel's overriding impulse was to comprehend all dimensions of existence as dialectically integrated in one unitary whole. In Hegel's view, all human thought and all reality is pervaded by contradiction, which alone makes possible the development of higher states of consciousness and higher states of being. Each phase of being contains within itself a self-contradiction, and it is this that serves as the motor of its movement to a higher and more complete phase. Through a continuing dialectical process of opposition and synthesis, the world is always in the process of completing itself. Whereas for most of the history of Western philosophy from Aristotle onward, the defining essence of opposites was that they were logically contradictory and mutually exclusive, for Hegel all opposites are logically necessary and mutually implicated elements in a larger truth. Truth is thus radically paradoxical.
Richard Tarnas, The Passion of the Western Mind: Understanding the Ideas that Have Shaped Our World View
