The Doppelganger or Double presents literature as the double of philosophy. There are historical reasons for this. The genesis of the Doppelganger is literature's response to the philosophical focus on subjectivity. The Doppelganger was coined by the German author Jean Paul in 1796 as a critique of Idealism's assertion of subjective autonomy, individuality and human agency. This critique prefigures post-War extrapolations of the subject as decentred. From this perspective, the Doppelganger has a family resemblance to current conceptualizations of subjectivity. It becomes the emblematic subject of modernity. This is the first significant study on the Doppelganger's influence on philosophical thought. The Doppelganger emerges as a hidden and unexplored element both in conceptions of subjectivity and in philosophy's relation to Doppelganger to read literature philosophically and to read philosophy as literature. The Doppelganger then appears instrumental in the self-conception of both literature and philosophy.