In this talk, the gradual emergence of the notion of the unconscious will be sketched, as it pertains to the tradition that runs from Schopenhauer to Sigmund Freud, via Eduard von Hartmann and Philipp Mainländer to Sabina Spielrein and C.G. Jung. Despite historical continuities, Schopenhauer's philosophical concept of the will is not synonymous with the unconscious. Indeed, Schopenhauer hardly uses the term in his writings. Therefore we will focus on:

- the popularisation of the term unconscious by v. Hartmann,
- the extent of Freud's adaption of Schopenhauer's ideas in his writings,
- the role of Phillip Mainländer's philosophy as a catalyst for the death drive.