and represses the passions, be
called temperance; and every virtue that strengthens the mind against
any passions whatever, be called fortitude. Many, both holy doctors,
as also philosophers, speak about these virtues in this sense: and in
this way the other virtues are contained under them. Wherefore all
the objections fail.

Secondly, they may be considered in point of their being denominated,
each one from that which is foremost in its respective matter, and
thus they are specific virtues, condivided with the others. Yet they
are called principal in comparison with the other virtues, on account
of the importance of their matter: so that prudence is the virtue
which commands; justice, the virtue which is about due actions
between equals; temperance, the virtue which suppresses desires for
the pleasures of touch; and fortitude, the virtue which strengthens
against dangers of death. Thus again do the objections fail: because
the other virtues may be principal in some other way, but these are
called principal by reason of their matter, as stated above.
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FOURTH ARTICLE [I-II, Q. 61, Art. 4]

Whether the Four Cardinal Virtues Differ from One Another?

Objection 1: It would seem that the above four virtues are not
diverse and distinct from one another. For Gregory says (Moral. xxii,
1): "There is no true prudence, unless it be just, temperate and
brave; no perfect temperance, that is not brave, just and prudent; no
sound fortitude, that is not prudent, temperate and just; no real
justice, without prudence, fortitude and temperance." But this would
not be so, if the above virtues were distinct from one another: since
the different species of one genus do not qualify one another.
Therefore the aforesaid virtues are not distinct from one another.

Obj. 2: Further, among things distinct from one another the function
of one is not attributed to another. But the function of temperance
is attributed to fortitude: for Ambrose says (De Offic. xxxvi):
"Rightly do we call it fortitude, when a man conquers himself, and is
not weakened and bent by any enticement." And of temperance he says
(De Offic. xliii, xlv) that it "safeguards the manner and order in
all things that we decide to do and say." Therefore it seems that
these virtues are not distinct from one another.

Obj. 3: Further, the Philosopher says (Ethic. ii, 4) that the
necessary conditions of virtue are first of all "that a man should
have kno