these three dialogues are found to make an advance upon the metaphysical
conceptions of the Republic. And we can more easily suppose that Plato
composed shorter writings after longer ones, than suppose that he lost hold
of further points of view which he had once attained.

It is more easy to find traces of the Pythagoreans, Eleatics, Megarians,
Cynics, Cyrenaics and of the ideas of Anaxagoras, in the Philebus, than to
say how much is due to each of them. Had we fuller records of those old
philosophers, we should probably find Plato in the midst of the fray
attempting to combine Eleatic and Pythagorean doctrines, and seeking to
find a truth beyond either Being or number; setting up his own concrete
conception of good against the abstract practical good of the Cynics, or
the abstract intellectual good of the Megarians, and his own idea of
classification against the denial of plurality in unity which is also
attributed to them; warring against the Eristics as destructive of truth,
as he had formerly fought against the Sophists; taking up a middle position
between the Cynics and Cyrenaics in his doctrine of pleasure; asserting
with more consistency than Anaxagoras the existence of an intelligent mind
and cause. Of the Heracliteans, whom he is said by Aristotle to have
cultivated in his youth, he speaks in the Philebus, as in the Theaetetus
and Cratylus, with irony and contempt. But we have not the knowledge which
would enable us to pursue further the line of reflection here indicated;
nor can we expect to find perfect clearness or order in the first efforts
of mankind to understand the working of their own minds. The ideas which
they are attempting to analyse, they are also in process of creating; the
abstract universals of which they are seeking to adjust the relations have
been already excluded by them from the category of relation.

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