existence on earth an evil, because almost all sufferings
can be borne by a patient and firm mind; since if the situation we are
placed in becomes either intolerable, or upon the whole more painful
than agreeable, it is our own fault that we remain in it.

But these philosophers took a further view of the question which
especially applied to moral evil. They considered that nothing could be
more groundless than to suppose that if there were no evil there could
be any good in the world; and they illustrated this position by asking
how we could know anything of temperance, fortitude or justice, unless
there were such things as excess, cowardice and injustice.

These were the doctrines of the Stoics, from whose sublime and
impracticable philosophy they seemed naturally enough to flow. Aulus
Gellius relates that the last-mentioned argument was expounded by
Chrysippus, in his work upon providence. The answer given by Plutarch
seems quite sufficient: "As well might you say that Achilles could not
have a fine head of hair unless Thersites had been bald; or that one
man's limbs could not be all sound if another had not the gout."

In truth, the Stoical doctrine proceeds upon the assumption that all
virtue is only the negative of vice; and is as absurd, if indeed it
be not the very same absurdity, as the doctrine which should deny the
existence of affirmative or positive truths, resolving them all into the
opposite of negative propositions. Indeed, if we even were to admit this
as an abstract position, the actual existence of evil would still be
unnecessary to the idea, and still more to the existence, of good. For
the conception of evil, the bare idea of its possibility, would be quite
sufficient, and there would be no occasion for a single example of it.

The other doctrine, that of two opposite principles, was embraced by
most of the other sects, as it should seem, at some period or other
of their inquiries. Plato himself, in his later works, was clearly
a supporter of the system; for he held that there were at least two
principles, a good and an evil; to which he added a third, the moderator
or mediator between them.

Whether this doctrine was, like many others, imported into Greece from
the East, or was the natural growth of the schools, we cannot ascertain.
Certain it is that the Greeks themselves believed it to have been taught
by Zoroaster in Asia, at least five centuries before the Trojan war; so
that it had an exi