The work draws on the theoretical work of C. Schmidt-Hellerau. Three concepts added by her are explored in greater depth: (1) the drive of self-preservation as part of the death drive, (2) the concept of the preunconscious, (3) the drive system. While the metaphor of Janus-facedness is used to understand drive and energy both as part of an abstract metapsychology and as a sensually perceptible phenomenon, the author introduces the metaphor of the knight´s move, borrowed from the game of chess, to characterise the property of drives as category jumpers. For this purpose, the author refers to the ontology of Nicolai Hartmann, whose basic assumptions the author applies pars pro toto to one of the known concepts of somatisation, and result in a new proposal for how to differentiate between somatic and psychic drives. Starting from a historical court case the ways are analysed in which the drive can or cannot be the cause of thought and action. The question of the extent to which energy in the two layers of being, soma and psyche, can be understood as physical on the one hand and psychic on the other is explored.