This paper analyses Heidegger’s controversial advancement of Husserl’s idea of philosophy and phenomenological research towards ‘the BeingQuestion’ and its relation to ‘Dasein’. It concentrates on Heidegger’s elision of Dilthey and Husserl’s different concepts of ‘Descriptive Psychology’ in his 1925 Summer Semester lecturecourse, with Husserl’s concept losing out in the competition, as background to the formulation of ‘the BeingQuestion’ in Being and Time (1927). It argues that Heidegger establishes his own position within phenomenology on the basis of a partial appropriation of Dilthey’s hermeneutical manner of thinking, an appropriation that was later radically called into question by Lévinas on Diltheyeanhermeneuticalphilosophical grounds.