 In 1766 Kant published his first work concerned with the possibility of metaphysics, which later became a central topic of his mature philosophy. Dreams of a Spirit-Seer Elucidated by Dreams of Metaphysics, which he wrote soon after publishing a short Essay on Maladies of the Mind (1764), was occasioned by Kant’s fascination with the Swedish visionary Emanuel Swedenborg (1688–1772), who claimed to have insight into a spirit world that enabled him to make a series of apparently miraculous predictions. In this curious work Kant satirically compares Swedenborg’s spirit-visions to the belief of rationalist metaphysicians in an immaterial soul that survives death, and he concludes that philosophical knowledge of either is impossible because human reason is limited to experience. The skeptical tone of Dreams is tempered, however, by Kant’s suggestion that “moral faith” nevertheless supports belief in an immaterial and immortal soul, even if it is not possible to attain metaphysical knowledge in this domain (2:373).