  Dasein is, then, our primary ‘object’ of study, and our point of investigative departure is Dasein's everyday encounters with entities. But what sort of philosophical method is appropriate for the ensuing examination? Famously, Heidegger's adopted method is a species of phenomenology. In the Heideggerian framework, however, phenomenology is not to be understood (as it sometimes is) as the study of how things merely appear in experience. Rather, in a recognizably Kantian staging of the idea, Heidegger follows Husserl (1913/1983) in conceiving of phenomenology as a theoretical enterprise that takes ordinary experience as its point of departure, but which, through an attentive and sensitive examination of that experience, aims to reveal the a priori, transcendental conditions that shape and structure it. In Heidegger's Being-centred project, these are the conditions “which, in every kind of Being that factical Dasein may possess, persist as determinative for the character of its Being” (Being and Time 5: 38). Presupposed by ordinary experience, these structures must in some sense be present with that experience, but they are not simply available to be read off from its surface, hence the need for disciplined and careful phenomenological analysis to reveal them as they are. So far so good. But, in a departure from the established Husserlian position, one that demonstrates the influence of Dilthey, Heidegger claims that phenomenology is not just transcendental, it is hermeneutic (for discussion, see e.g., Caputo 1984, Kisiel 2002 chapter 8). In other words, its goal is always to deliver an interpretation of Being, an interpretation that, on the one hand, is guided by certain historically embedded ways of thinking (ways of taking-as reflected in Dasein's preontological understanding of Being) that the philosopher as Dasein and as interpreter brings to the task, and, on the other hand, is ceaselessly open to revision, enhancement and replacement. For Heidegger, this hermeneutic structure is not a limitation on understanding, but a precondition of it, and philosophical understanding (conceived as fundamental ontology) is no exception. Thus Being and Time itself has a spiral structure in which a sequence of reinterpretations produces an ever more illuminating comprehension of Being. As Heidegger puts it later in the text: