'being': being as distinct from not-being. Being or not-being – that is the question. Being means being-present, existentia. For example, the earth is, God is, i.e. exists or is actual. Being in the sense of actuality. To be sure, we saw that this is only one of the meanings of being belonging to the originary structure of the concept of being in everyday understanding. It would, therefore, be a fundamental misunderstanding of the problem of being were we to pose it as exclusively or primarily the problem of actuality. Nevertheless, and precisely in regard to antiquity, we cannot pass over the question of whether and how the concept of actuality – existence in the traditional sense, as e.g. in Kant – involves the fundamental meaning of οὐσία as constant presence. We can immediately see that no progress can be made if we remain at the level of linguistic discussions.
To comprehend what is problematic in the word 'actuality', we must inquire into the philosophical term to which it corresponds. 'Actuality' [Wirklichkeit] is a translation of the Latin word actualitas - ens in actu, i.e. a being in so far as it is actually present, as distinct from an ens ratione, ens in potentia, i.e. a being insofar as it is merely possible. However, actualitas is itself the Latin translation of the Greek word ἐνέργεια. Our word 'energy', in the sense of force, has nothing to do with this. What ἐνέργεια means, as a philosophical expression for existence, actuality, being-present, is something totally different from 'force'. To conceive ἐνέργεια as force betrays an external and superficial understanding of the concept, in a similar manner as Dionysodorus' argumentation in respect of παρουσία. ἐνέργεια ὄν means actual beings as distinct from δυνάμει ὄν, mere possible beings.
How then is this actuality of the actual to be comprehended? What does ἐνέργεια mean in its substantive meaning, not just according to the dictionary? Does this understanding of being support our more general claim that being means constant presence? What does ἐνέργεια have to do with constant presence? We certainly cannot discover this without entering into the ancient Greek problematic of being (Plato and Aristotle).
However, we have already seen how Aristotle develops the problem of being in terms of the problem of movement, where the latter means change, μεταβολή. Change involves the disappearance of something and the appearance of something else: ἀπουσία and παρουσία. Now it is very significant that Aristotle, precisely where he presses forward into the genuine depths of the essence of movement, avails himself of the concepts ἐνέργεια and δυνάμει, and in such a way that, roughly
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