Of the ideas he treats in the same sceptical spirit which appears in his criticism of them in the Parmenides.
Parmenides had asserted, on priori grounds, the existence of "the One."
This argument of Parmenides is the memorable argument known under the name of ὁ τρίτος ἄνθρωπος.
Here, is in the Parmenides, he means something not really different from generalization.
As far as I can see, the puzzling antinomies in the Parmenides have no other purpose.
To the passionate language of Parmenides, Plato replies in a strain equally passionate:—What!
You propose to me, Parmenides (remarks Sokrates), a work of awful magnitude.
To the Parmenides, the Sophist stands in a less defined and more remote relation.
We must therefore suppose that the Parmenides was composed later than Aristotle, and borrowed this objection from Aristotle.
He felt no incongruity in the veteran Parmenides correcting the youthful Socrates.