According to my thesis, the genetic notion of the horizon is first and foremost meant to qualify the horizons of transcendental subjectivity. This chapter argues that phenomenology cannot disclose the horizons of transcendental subjectivity for as long as it understand the phenomenological reduction in accordance with how it was spelled out in the confines of static phenomenology. I argue that the philosophical significance of the new path to the reduction, which Husserl has introduced in First Philosophy II, lies in the fact that it enables phenomenology to disclose the distinct horizons of transcendental subjectivity. I suggest that from First Philosophy II, one can derive a new notion of the horizon, conceived as the milieu of concealed sense accomplishments, i.e., as the very conceptual space that genetic phenomenology aims to thematize. On such a basis, the question of the origins of the horizon obtains its specifically phenomenological sense: it merges with the question of sense-formation itself.