wolf, flees at once, because it
has no superior counteracting appetite. On the contrary, man is not
moved at once, according to the irascible and concupiscible
appetites: but he awaits the command of the will, which is the
superior appetite. For wherever there is order among a number of
motive powers, the second only moves by virtue of the first:
wherefore the lower appetite is not sufficient to cause movement,
unless the higher appetite consents. And this is what the Philosopher
says (De Anima iii, 11), that "the higher appetite moves the lower
appetite, as the higher sphere moves the lower." In this way,
therefore, the irascible and concupiscible are subject to reason.

Reply Obj. 1: Sensuality is signified by the serpent, in what is
proper to it as a sensitive power. But the irascible and
concupiscible powers denominate the sensitive appetite rather on the
part of the act, to which they are led by the reason, as we have said.

Reply Obj. 2: As the Philosopher says (Polit. i, 2): "We observe in
an animal a despotic and a politic principle: for the soul dominates
the body by a despotic power; but the intellect dominates the
appetite by a politic and royal power." For a power is called
despotic whereby a man rules his slaves, who have not the right to
resist in any way the orders of the one that commands them, since
they have nothing of their own. But that power is called politic and
royal by which a man rules over free subjects, who, though subject
to the government of the ruler, have nevertheless something of their
own, by reason of which they can resist the orders of him who
commands. And so, the soul is said to rule the body by a despotic
power, because the members of the body cannot in any way resist the
sway of the soul, but at the soul's command both hand and foot, and
whatever member is naturally moved by voluntary movement, are moved
at once. But the intellect or reason is said to rule the irascible
and concupiscible by a politic power: because the sensitive appetite
has something of its own, by virtue whereof it can resist the
commands of reason. For the sensitive appetite is naturally moved,
not only by the estimative power in other animals, and in man by the
cogitative power which the universal reason guides, but also by the
imagination and sense. Whence it is that we experience that the
irascible and concupiscible powers do resist reason, inasmuch as we
sense or imagine something pleasant, which reason f