This thesis understands itself as a contribution to the continuing discussion about the internal unity of Goethe's Faust. The work's presumed unity is genetically interpreted: regarding the origin (author), the elaboration-process (including direct and indirect influences by other persons) and the result (text) of Goethe's tragedy. The initial idea is that Faust -- as any other important and authentic literary work -- does not only represent the creation of an individual, but expresses also the very spirit of its time.This idea leads logically to the question of the significance of Kant's and Fichte's philosophy which determined essentially the spiritual "horizon" in Germany during the years I780-I830 and which had been very carefully studied by Schiller and Goethe.The thesis tries to point out that the genetic unity of  Faust  can be shown by illuminating and making transparent this "horizon".