rational good, it does not need to be prompted by any habit to embrace
rational good in what concerns only the inward administration of the
agent's own self. There is no difficulty in that department, provided
the sensitive appetite be kept in hand by fortitude and temperance.
But where there is question of external relations with other men, it
is not enough that the sensitive appetite be regulated, but a third
virtue is necessary, the habit of justice, to be planted in the will,
which would otherwise be too weak to attend steadily to points, not of
the agent's own good merely, but of the good of other men.

5. Thus we have the four cardinal virtues: prudence, a habit of the
intellect; temperance, a habit of the concupiscible appetite;
fortitude, a habit of the irascible appetite; and justice, a habit of
the will. Temperance and Fortitude in the Home Department; Justice for
Foreign Affairs; with Prudence for Premier. Or, to use another
comparison, borrowed from Plato, prudence is the health of the soul,
temperance its beauty, fortitude its strength, and justice its wealth.

_Readings_.--St. Thos., 1a 2a, q. 61, art. 2, in corp.; _ib_., q. 56,
art. 4, in corp., ad 1-3; _ib_., q. 56, art. 6, in corp., ad 1, 3;
_ib_., q. 59, art. 4, in corp., ad 2; Plato, _Laws_, 631 B, C.


SECTION VI.--_Of Prudence_.


1. Prudence is _right reason applied to practice_, or more fully it
may be defined, the habit of intellectual discernment that enables one
to hit upon the golden mean of moral virtue and the way to secure that
mean. Thus prudence tells one what amount of punishment is proper for