constellation of colours, an object that is no longer sensory at all. And yet we see (perceive), in the sense that we comport ourselves to what is presented to us.

When we so naturally say 'we see the book', we use 'see' in a meaning that is quite obvious and normal, and about which we become suspicious only when someone makes us pay closer attention. The latter is precisely what Plato did with his discovery of the so-called 'ideas'. This discovery was not some far-flung speculation on the part of Plato, but relates to what everyone sees and grasps in comportment to beings. Plato just pointed this out with previously unknown power and assurance. For what we see there, a 'book', is clearly something different to 'black', 'hard', 'soft' etc. What is sighted in this seeing is the ἰδέα, the εἶδος;. 'Idea' is therefore the look [Anblick] of something as something. It is through these looks that individual things present themselves as this and that, as being-present. Presence [Anwesenheit] for the Greeks is παρουσία, shortened as οὐσία, and means being. That something is means that it is present [es ist anwesend], or better: that it presences [west an] in the present [Gegenwart]. The look, ἰδέα, thus gives what something presences as, i.e. what a thing is, its being.

According to Aristotle this is the δευτέρα οὐσία, but the πρώτη is what is more present, the καθ᾽ ἕκαστον.8

We said: according to Plato there is, over and above the particular things (the shadows), something else, namely the ideas. If we have carefully followed the above considerations, something must have dawned on us. At least until a few moments ago, we ourselves belonged to those who thought they saw only the various particular things: book, door, house. We did not suspect that in order to see this book, door, and so forth, we must already understand what 'book' and 'door' mean. Understanding what such things mean is nothing else but the seeing of the look, the ἰδέα. In the idea we see what every being is and how it is, in short the being of beings [das Sein des Seienden].

This seeing of the ἰδέα Plato also calls νοεῖν, perceiving, or νοῦς, reason in the strict sense: the capacity to perceive.

Plato now grasps the νοεῖν of Parmenides9 as the ἰδεῖν of the ἰδέα, of the ἀγαθόν, ἐπέκεινα τῆς οὐσίας. Kant too says clearly and unambiguously that 'reason' is the 'faculty of ideas',10 although he uses 'idea' in a broadened Platonic and also in a restricted sense.

The seeing of the idea, i.e. the understanding of what-being and how-being, in short of being, first allows beings to be recognized as the beings



Martin Heidegger (GA 34) The Essence of Truth