E. T. A. Hoffmann famously lauded Beethoven’s ability to separate his ego from the world of tones, an image of autonomy that resonated with Idealist celebrations of human will. This essay challenges the underlying principle of sovereignty so central to Beethoven reception by examining the composer’s attitudes towards nature, both the natural world around him and his own physical nature. By examining contemporaneous notions of hypochondria, it links the interrelationship between physiology and psychology to Beethoven and his contemporaries’ artistic aspirations and works. If Idealists celebrated the power of spirit and the sovereignty of the will, they often did so in response to powerful experiences of their own physical nature.