Full Idea
The absolute good and the beautiful and all which we conceive to be absolute ideas are unknown to us.
Gist of Idea
Absolute ideas, such as the Good and the Beautiful, cannot be known by us
Source
Plato (Parmenides [c.366 BCE], 134c)
Book Reference
Plato: 'Plato IV (Cratylus,Parmenides,Hippias Maj, Min)', ed/tr. Fowler,H.N. [Harvard Loeb 1926], p.227
A Reaction
These seems to thoroughly pre-empt Plato's Theory of Forms a century before he created it. Which shows (as Simone Weil says) that Plato was just part of a long tradition.