 Wundt divides up the sciences into two large families, the “formal” sciences and the “real” sciences. The former include mathematics; the latter study the natural and spiritual aspects of  reality,[49]  and correspondingly are divided into the natural and the human sciences. The human sciences in turn are divided into two genera, one of which deals with spiritual processes (geistige Vorgänge), the other with spiritual products (geistige Erzeugnisse). The former just is the science of psychology; the latter includes the general study of these products as such (e.g., philology, political science, law, religion, etc.), as well as the parallel historical study of these products as they have in fact been created (This taxonomy is given in SP I: 19–20). Since the process precedes the product (cf. Kusch 1995: 132), psychology as “the doctrine of spiritual [geistig] processes as such” is the foundation of all the other human sciences (SP I:  20).[50]  Philosophy, in turn, takes psychology’s results and again abstracts from them the normative rules governing the organization of the human and natural sciences, something the latter cannot do themselves. In this way psychology as a science mediates between the sciences and philosophy.