e earliest justification of liberty of
thought we have two significant claims affirmed: the indefeasible right
of the conscience of the individual --a claim on which later struggles
for liberty were to turn; and the social importance of discussion and
criticism. The former claim is not based on argument but on intuition;
it rests in fact on the assumption

[35] of some sort of superhuman moral principle, and to those who, not
having the same personal experience as Socrates, reject this assumption,
his pleading does not carry weight. The second claim, after the
experience of more than 2,000 years, can be formulated more
comprehensively now with bearings of which he did not dream.

The circumstances of the trial of Socrates illustrate both the tolerance
and the intolerance which prevailed at Athens. His long immunity, the
fact that he was at last indicted from political motives and perhaps
personal also, the large minority in his favour, all show that thought
was normally free, and that the mass of intolerance which existed was
only fitfully invoked, and perhaps most often to serve other purposes. I
may mention the case of the philosopher Aristotle, who some seventy
years later left Athens because he was menaced by a prosecution for
blasphemy, the charge being a pretext for attacking one who belonged to
a certain political party. The persecution of opinion was never
organized.

It may seem curious that to find the persecuting spirit in Greece we
have to turn to the philosophers. Plato, the most brilliant disciple of
Socrates, constructed in his later years an ideal State. In this State
he instituted

[36] a religion considerably different from the current religion, and
proposed to compel all the citizens to believe in his gods on pain of
death or imprisonment. All freedom of discussion was excluded under the
cast-iron system which he conceived. But the point of interest in his
attitude is that he did not care much whether a religion was true, but
only whether it was morally useful; he was prepared to promote morality
by edifying fables; and he condemned the popular mythology not because
it was false, but because it did not make for righteousness.

The outcome of the large freedom permitted at Athens was a series of
philosophies which had a common source in the conversations of Socrates.
Plato, Aristotle, the Stoics, the Epicureans, the Sceptics--it may be
maintained that the efforts of thought represented by these na