Developing the theory of an entity which exists independently of human experience which is the cause of all sensations, for 10 points, name this text which introduces the "thing-in-itself" as a correction to Kant's metaphysics, a work of Arthur Schopenhauer.
This work includes an extended analysis of the purpose and nature of architecture as a conflict between rigidity and gravity to illustrate how indistinctly originating human ideas are brought to clarity.  The author uses the analogy of magnetism and electricity as the same force to compare to the dual nature of two central concepts, and another section of this work reduces another philosopher's theory of twelve categories of understanding into the single category of causality.  This work introspectively deduces that humans perceive their bodies by means of two of the title concepts, both of which consist of the same reality and differ only due to alternate human perspectives.  Developing the theory of an entity which exists independently of human experience which is the cause of all sensations, for 10 points, name this text which introduces the "thing-in-itself" as a correction to Kant's metaphysics, a work of Arthur Schopenhauer.
This work includes an extended analysis of the purpose and nature of architecture as a conflict between rigidity and gravity to illustrate how indistinctly originating human ideas are brought to clarity.  
The {World} as {Will} and {Representation} [accept The {World} as {Will} and {Idea}; accept {Die Welt als Wille und Vorstellung}]