This chapter discusses two opposing answers to the question of whether self-formation is possible: Kant’s view of the self as an autonomous being is confronted with two contemporary representations of a determinist view of the self, namely situationism and brain-determinism. It is shown that advocates and opponents of autonomy and free will do not agree on the question of whether and to what extent consciousness/mind, the brain or the environment can be attributed causal efficacy and control. However, they often share the views that a distinction should be made between opposing realms and that freedom can only be attributed to an agent that is not fundamentally affected or determined by something else, which is a precondition to be able to cause and control actions, make decisions and utilize the outside world. This chapter argues that both opposing positions assume a false categorical distinction between an “inside” and an “outside” realm, and so fall back in or are not able to sufficiently overcome an essentialist and dualist view of the self.