Martin Heidegger said this quote
“ The *second task* consists in distinguishing the mode of knowing operative in ontology as science of Being, and this requires us to *work out the methodological structure of ontological-transcendental differentiation*. In early antiquity it was already seen that Being and its attributes in a certain way underlie beings and precede them and so are *a proteron*, an earlier. The term denoting this character by which Being precedes beings is the expression *a priori*, *apriority*, being earlier or prior. As *a priori*, Being is earlier than beings. The meaning of this *a priori*, the sense of the earlier and its possibility, has never been cleared up. The question has not even once been raised as to why the determinations of Being and Being itself must have this character of priority and how such priority is possible. To be earlier is a determination of time, but it does not pertain to the temporal order of the time that we measure by the clock; rather, it is an earlier that belongs to the inverted world. Therefore, this earlier which characterises Being is taken by the popular understanding to be the later. Only the interpretation of Being by way of temporality can make clear why and how this feature of being earlier, apriority, goes together with Being. The *a priori* character of Being and of all the structures of Being accordingly calls for a specific kind of approach and way of apprehending Being―*a priori cognition*.The basic components of *a priori* cognition constitute what we call *phenomenology*. Phenomenology is the name for the method of ontology, that is, of scientific philosophy. Rightly conceived, phenomenology is the concept of a method. It is therefore precluded from the start that phenomenology should pronounce any theses about Being which have specific content, thus adopting a so-called standpoint. ―Martin Heidegger, from_The Basic Problems of Phenomenology_ ”