of warning is necessary before we enter upon the details of
this problem. Plato frequently speaks of all moral activity aiming at,
and ending in, happiness. With modern phrases ringing in our ears, we
might easily suppose this to mean that Plato is a utilitarian. The
utilitarianism of Bentham and Mill is distinguished by the fact that
it places the end of morality in happiness. Yet Plato was not a
utilitarian, and would unhesitatingly have condemned the theory of
Mill. He {221} would have found it identical in principle with the
Sophistic doctrine that pleasure is the end of virtue. The only
difference is that, whereas the Sophists identified virtue with the
pleasure of the individual, Mill makes it the pleasure of the
community. That act is right which leads to "the greatest happiness of
the greatest number." In practice, of course, this makes a tremendous
difference. But the principle is equally objectionable because, like
the Sophistic theory, it founds morality upon mere feeling, instead of
upon reason, and because it places the end of morality outside
morality itself. Yet the formula of Mill, that the end of morals is
happiness, seems the same as Plato's formula. What is the difference?

The fact is that what Mill calls happiness Plato would have called
pleasure. Pleasure is the satisfaction of one's desires, whether they
are noble or ignoble. Then what is happiness? It can only be defined
as the general harmonious well-being of life. Only that man is happy
whose soul is in the state it ought to be in, only in fact the just,
the good, and the moral man. Happiness has nothing to do with
pleasure. If you could conceive an absolutely just and upright man,
who was yet weighed down with every possible misery and disaster, in
whose life pleasure had no part, such a man would still be absolutely
happy. Happiness is, therefore, in Plato, merely another name for the
_summum bonum_. In saying that the _summum bonum_ is happiness, Plato
is not telling us anything about it. He is merely giving it a new
name. And we are still left to enquire: what is the _summum bonum_?
what is happiness?

Plato's answer, as indeed his whole ethics, is but {222} an
application of the theory of Ideas. But here we can distinguish two
different and, to some extent, inconsistent strains of thought, which
exist side by side in Plato, and perpetually struggle for the mastery.
Both views depend upon the theory of Ideas. In the first place, the
Idea,