re is nothing but close reasoning, hard
and laborious discussion.

The twin dialogues, "Gorgias" and "Theaetetus" are probably the
earliest of this group. They result in nothing very definite, and are
chiefly negative in character. Plato is here engaged merely in a
preparatory clearing of the ground. The "Gorgias" discusses and
refutes the Sophistic identification of virtue and pleasure, and
attempts to show, as against it, that the good must be something
objectively existent, and independent of the pleasure of the
individual. The "Theaetetus," similarly, shows that truth is not, as
the Sophists thought, merely the subjective impression of the
individual, but is something objectively true in itself. The other
{175} dialogues of the group are the "Sophist," the "Statesman," and
the "Parmenides." The "Sophist" discusses Being and not-being, and
their relationship to the theory of Ideas. The "Parmenides" inquires
whether the absolute reality is to be regarded, in the manner of the
Eleatics, as an abstract One. It gives us, therefore, Plato's
conception of the relation of his own philosophy to Eleaticism.

The dialogues of the third group are the work of Plato's maturity. He
has now completely mastered his thought, and turns it with ease in all
directions. Hence the style returns to the lucidity and purity of the
first period. If the first period was marked chiefly by literary
grace, the second by depth of thought, the third period combines both.
The perfect substance is now moulded in the perfect form. But a
peculiarity of all the dialogues of this period is that they take it
for granted that the theory of Ideas is already established and
familiar to the reader. They proceed to apply it to all departments of
thought. The second period was concerned with the formulation and
proof of the theory of Ideas, the third period undertakes its
systematic application. Thus the "Symposium," which has for its
subject the metaphysic of love, attempts to connect man's feeling for
beauty with the intellectual knowledge of the Ideas. The "Philebus"
applies the theory of Ideas to the sphere of ethics, the "Timaeus" to
the sphere of physics, and the "Republic" to the sphere of politics.
The "Phaedo" founds the doctrine of the immortality of the soul upon
the theory of Ideas. The "Phaedrus" is probably to be grouped with the
"Symposium." The beauty, grace, and lucidity of the style, and the
fact that it assumes throughout that {176} the the