The last in a series of examinations, this paper articulates Husserl's mature position on the nature of a phenomenologically informed human science. Falling between the naïve positivity of a naturalistic approach to psychology and the transcendental view of consciousness at the base of phenomenological philosophy, we argue that a human scientific psychology—while not itself transcendental in nature needs to re-arise upon the transcendental ground as an empirical—but no longer transcendentally naïve—discipline through Husserl's notion of the "return to positivity." This notion (...) of the return allows us to avoid "transcendental psychologism," differentiating psychological from transcendental subjectivity but from a transcendental, rather than naïve perspective. In this way, the return to positivity reclaims psychology as a worldly, but no longer naïve, discipline. To facilitate an understanding of the different perspectives in question, and the process of leaving the naturalistic perspective in order to return to it once armed with a transcendental understanding and its associated tools, we continue to develop the illustrative example of anorexia provided in the first part of this series. In conclusion, we discuss the implications of this framework for transcendental reforms both of clinical practice and of psychological research. (shrink)