be a privileged form of
liberty of action, or why society should lay down its arms of defence
and fold its hands, when it is persuaded that harm is threatened to it
through the speech of any of its members. The Government has to judge of
the danger, and its judgment may be wrong; but if it is convinced that
harm is being done, is it not its plain duty to interfere?

This argument supplies an apology for the suppression of free opinion by
Governments in ancient and modern times. It can be urged for the
Inquisition, for Censorship of the Press, for Blasphemy laws, for all
coercive measures of the kind, that, if excessive or ill-judged, they
were intended to protect society against what their authors sincerely
believed to be grave injury, and were simple acts of duty. (This
apology, of course, does not extend to acts done for the sake of the
alleged good of the victims themselves, namely, to secure their future
salvation.)

Nowadays we condemn all such measures

[235] and disallow the right of the State to interfere with the free
expression of opinion. So deeply is the doctrine of liberty seated in
our minds that we find it difficult to make allowances for the coercive
practices of our misguided ancestors. How is this doctrine justified? It
rests on no abstract basis, on no principle independent of society
itself, but entirely on considerations of utility.

We saw how Socrates indicated the social value of freedom of discussion.
We saw how Milton observed that such freedom was necessary for the
advance of knowledge. But in the period during which the cause of
toleration was fought for and practically won, the argument more
generally used was the injustice of punishing a man for opinions which
he honestly held and could not help holding, since conviction is not a
matter of will; in other words, the argument that error is not a crime
and that it is therefore unjust to punish it. This argument, however,
does not prove the case for freedom of discussion. The advocate of
coercion may reply: We admit that it is unjust to punish a man for
private erroneous beliefs; but it is not unjust to forbid the
propagation of such beliefs if we are convinced that they are harmful;
it is not unjust to punish him, not for holding them, but for publishing
them. The truth

[236] is that, in examining principles, the word just is misleading. All
the virtues are based on experience, physiological or social, and
justice is no exception. Just