edge, the knowledge of
esteemed and useful citizens, which cannot be the highest knowledge,
since these citizens fail to impart it even to their own sons.

In this dialogue, we have Plato's view of Immortality, which comprises
both pre-existence and post-existence. The pre-existence is used to
explain the derivation of general notions, or Ideas, which are
antecedent to the perceptions of sense.

In PROTAGORAS, we find one of the most important of the ethical
discussions of Plato. It proceeds from the same question--Is virtue
teachable?--Sokrates as usual expressing his doubts on the point.
Protagoras then delivers a splendid harangue, showing how virtue is
taught--namely, by the practice of society in approving, condemning,
rewarding, punishing the actions of individuals. From childhood
upward, every human being in society is a witness to the moral
procedure of society, and by degrees both knows, and conforms to, the
maxims of virtue of the society. Protagoras himself as a professed
teacher, or sophist, can improve but little upon, this habitual
inculcation. Sokrates, at the end of the harangue, puts in his usual
questions tending to bring out the essence or definition of virtue,
and soon drives Protagoras into a corner, bringing him to admit a view
nowhere else developed in Plato, that Pleasure is the only good, Pain
the only evil, and that the science of Good and Evil consists in
Measuring, and in choosing between conflicting pleasures and
pains--preferring the greater pleasure to the less, the less pain to
the greater. For example, courage is a wise estimate of things
terrible and things not terrible. In consistency with the doctrine
that Knowledge is virtue, it is maintained here as elsewhere, that a
man knowing good and evil must act upon that knowledge. Plato often
repeats his theory of Measurement, but never again specifically
intimates that the things to be measured are pleasures and pains. And
neither here nor elsewhere, does he suppose the virtuous man taking
directly into his calculation the pleasures and pains of other
persons.

GORGIAS, one of the most renowned of the dialogues in point of
composition, is also ethical, but at variance with the Protagoras, and
more in accordance with Plato's predominating views. The professed
subject is Rhetoric, which, as an art, Sokrates professes to hold in
contempt. The dialogue begins with the position that men are prompted
by the desire of good, but proceeds to the