Ereignis is often translated as event---the event of appropriation. If philosophy used to think in terms of idea, as energeia, as actualitas, does it now think in terms of appropriation? I've always suspected the background to all this is Aristotle and a metaphysics of becoming. Heidegger’s concern is as not “being” (the givenness or availability of entities for human engagement) of classical metaphysics, but rather what brings about being, namely Ereignis, the opening of clearing within which entities can appear as this or that. It is an enabling power.