clearly better than slowness and quietness?

Clearly they are.

Then temperance is not quietness, nor is the temperate life quiet,--
certainly not upon this view; for the life which is temperate is supposed
to be the good. And of two things, one is true,--either never, or very
seldom, do the quiet actions in life appear to be better than the quick and
energetic ones; or supposing that of the nobler actions, there are as many
quiet, as quick and vehement: still, even if we grant this, temperance
will not be acting quietly any more than acting quickly and energetically,
either in walking or talking or in anything else; nor will the quiet life
be more temperate than the unquiet, seeing that temperance is admitted by
us to be a good and noble thing, and the quick have been shown to be as
good as the quiet.

I think, he said, Socrates, that you are right.

Then once more, Charmides, I said, fix your attention, and look within;
consider the effect which temperance has upon yourself, and the nature of
that which has the effect. Think over all this, and, like a brave youth,
tell me--What is temperance?

After a moment's pause, in which he made a real manly effort to think, he
said: My opinion is, Socrates, that temperance makes a man ashamed or
modest, and that temperance is the same as modesty.

Very good, I said; and did you not admit, just now, that temperance is
noble?