nd this is
clear from their relations to their respective objects and acts. For
the act of _understanding_ implies the simple acceptation of
something; whence we say that we understand first principles, which
are known of themselves without any comparison. But to _reason,_
properly speaking, is to come from one thing to the knowledge of
another: wherefore, properly speaking, we reason about conclusions,
which are known from the principles. In like manner on the part of
the appetite to "will" implies the simple appetite for something:
wherefore the will is said to regard the end, which is desired for
itself. But to "choose" is to desire something for the sake of
obtaining something else: wherefore, properly speaking, it regards
the means to the end. Now, in matters of knowledge, the principles
are related to the conclusion to which we assent on account of the
principles: just as, in appetitive matters, the end is related to
the means, which is desired on account of the end. Wherefore it is
evident that as the intellect is to reason, so is the will to the
power of choice, which is free-will. But it has been shown above (Q.
79, A. 8) that it belongs to the same power both to understand and to
reason, even as it belongs to the same power to be at rest and to be
in movement. Wherefore it belongs also to the same power to will and
to choose: and on this account the will and the free-will are not two
powers, but one.

Reply Obj. 1: _Boulesis_ is distinct from _thelesis_ on account of a
distinction, not of powers, but of acts.

Reply Obj. 2: Choice and will--that is, the act of willing--are
different acts: yet they belong to the same power, as also to
understand and to reason, as we have said.

Reply Obj. 3: The intellect is compared to the will as moving the
will. And therefore there is no need to distinguish in the will an
active and a passive will.
_______________________

QUESTION 84

HOW THE SOUL WHILE UNITED TO THE BODY UNDERSTANDS CORPOREAL THINGS
BENEATH IT
(In Eight Articles)

We now have to consider the acts of the soul in regard to the
intellectual and the appetitive powers: for the other powers of the
soul do not come directly under the consideration of the theologian.
Furthermore, the acts of the appetitive part of the soul come under
the consideration of the science of morals; wherefore we shall treat
of them in the second part of this work, to which the consideration
of moral matters belongs. But of th