the thing known and also gives the power (of knowing) to the knower, this, I say, is the idea of the good."

The "allegory" mentions the sun as the image for the idea of the good. What does the essence of this idea consist in? As iSta the good is something that shines, thus something that provides vision, thus in tum something visible and hence knowable, in fact: ἐν τῷ γνωστῷ τελευταία ἡ τοῦ ἀγαθοῦ ἰδέα καὶ μόγις ὁρᾶσθαι (517 b8). "In the sphere of what can be known, the idea of the good is the power of visibility that accomplishes all shining forth and that therefore is properly seen only last, in fact it is hardly (only with great pains) really seen at all."

We translate τὸ ἀγαθόνa with the apparently understandable term "the good." Most often we think of this as the "moral good," which is so called because it is in conformity with the moral law. [133 {GA 9: 227}] This interpretation falls outside Greek thought, even though Plato's interpretation of the ἀγαθόν as idea offers the occasion for thinking of"the good" "morally" and ultimately for reckoning it to be a "value." The notion of value that came into fashion in the nineteenth century in the wake of the modem conception of "truth" is the last and at the same time the weakest offspring of ἀγαθόν. Insofar as "value" and interpretation in terms of "values" are what sustains Nietzsche's metaphysics - in the absolute form of a "revaluation of all values" - and since for him all knowledge takes its departure from the metaphysical origin of"value," to that extent Nietzsche is the most unrestrained Platonist in the history of Western metaphysics. However, insofar as he understands value as the condition of the possibility of "life," a condition posited by "life itself," Nietzsche has held on to the essence of ἀγαθόν with much less prejudice than those who go chasing after the absurdity of "intrinsically valid values."

Moreover if we follow modem philosophy and think the essence of the "idea" as perceptio ("subjective representation"), then we find in the "idea of the good" a "value" present somewhere in itself, of which in addition we have an "idea." This "idea" must naturally be the highest because what matters is that everything run its course in the "good" (in the well-being of prosperity or in the orderliness of an order). Within this modem way of thinking there is absolutely nothing more to grasp of the original essence of Plato's ἰδέα τοῦ ἀγαθοῦ).

In Greek thought τὸ ἀγαθόν means that which is capable of something and enables another to be capable of something. Every ἰδέα, the visible form of something, provides a look at what a being is in each case. Thus

a First edition, 1947: The ἀγαθόν certainly is an ἰδέα, but no longer present, and therefore hardly visible.


Martin Heidegger (GA 9) Plato's Doctrine of Truth