The image of nature as akin to abandonment that follows from Heidegger´s analysis of Rilke´s Muzot poem in Wozu Dichter brings to mind the idea that to make something exist is not yet to care for it. Nature is careless, Rilke says, and our Natura is also such that it throws us in risk. Nature is no museum and has no preservatives. Our essences are such that they throw us towards existence and, with no attachment, take no special care of our fate. The centre of all beings are like epicentres, explosive and centrifugal sources. This friction between existence as springing from Natura - an exigentia essentiae - and the Verlassenheit that is hosted in the very dettachment of what makes things happen points at an interia of existence: it survives its sponsors. Not that whatever promotes an instauration cares to keep sponsoring what was brought to the world. It leaves things to their own devices (up for grabs).
Nature is no museum, and yet it is another kind of assemblage (of floor made of left-overs). These left-over character is what makes nature open - it produces raw material while throwing elements to existence. This assemblage is not of what has been equally intesively being sponsored - it is composed of what is left, thrown away, left in the open. No Oikos where things take care of each other and of themselves. (One can then choose between a centrifugal and a centripetal ethical stance: that of spreading and spending and that of care and preservation - but this is somehow a later moment, it is not in itself in the exigentia essentiae if it is plagued with Verlassenheit.) Surely, Leibniz´s exigentia essentiae, in contrast, comes with the stamp of care (through the effectiveness of intraworld compossibility). Leibniz admits of no junk worlds (where all things are part of something else). His internal relations point at some kind of priority of the whole.