Before entering into this problem in more detail, we must note the implications of the quoted passage for our task of interpreting the fundamental word ουσία. That the interpretation and description of μεταβολή is oriented to absence and presence – indeed that this was, in a certain sense, already the case with Plato, who speaks of change from nothing to being and vice versa – to clearly see and understand this is of the greatest importance. Change in colour, for example. is conceived as the disappearance of one colour and the appearance of another. In the case of processes, i.e. of what we call 'becoming' in the narrower sense - a white piece of chalk becoming a red piece of chalk – there is something which underlies this change: ὑπο, something remains: μένον. The interpretation of the essence of movement proceeds through determinations of remaining and not-remaining, of remaining present and remaining absent.
To be noted is that becoming and origination basically mean: obtaining being, coming into being, coming to so-and-so-being. It is evident that change involves being-other, and thus a connection between being and constancy. To be constant (to remain) means to endure in constant presence; beingness, ουσία, is understood as constant presence.
Yet we have already seen that what we attributed to ουσία is in fact only expressed in παρουσία: παρά means 'next to', 'being adjacent' in a series, being immediately present. To be sure, these are the moments of meaning which are immediately intended when Greeks understand ουσία in the usual sense. So we are forced to the thesis that ουσία always means – whether or not this is made explicit – παρουσία, and that only for this reason can ἀπουσία express deprivation, i.e. lack of presence. In absence it is not essence but presence which is lacking; thus 'essence-hood', ουσία, at bottom means presence. The Greeks understood beingness in the sense of constant presence.
b) Being and What-Being. ουσία as the παρουσία of the εἶδος
It would. admittedly. be a very great error were we to think that everything has now been clarified. We would completely close ourselves off from the correct interpretation of the Greek understanding of being were we to overlook the fact that the clarification of this particular kind of understanding – the understanding of something self-evident yet also ungrasped (constant presence, presence in general. ουσία; more sharply: παρουσία) – involves constant struggle.
At first, the Greeks find this almost natural meaning of being, which we now formulate as presence, so very problematic that they cannot even
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