Chapter 5, “The Guiding Thread of Inner Experience”, explores the regulative use of the idea of the soul with regard to inner experience (as discussed in the Appendix to the Transcendental Dialectic of the first Critique). The chapter argues that the idea of the soul provides a presentation (Darstellung) of a mental whole in relation to which we can first determine inner appearances, without cognizing the whole as such. Employed as an “analogue of a schema” (A655/B693), the idea substitutes for all those schemata that cannot be applied to inner appearances, including the schema of persistence, and outlines the domain within which inner experience can be operative as empirical cognition of inner appearances. The chapter thus establishes the first central thesis of my view, which I develop in contrast to two rival interpretations: the noumenal view, which conceives of the soul as a noumenal substance, and the fictional view, according to which the soul is a mere fiction.