Things make us happy because they are good, and when we possess
them, we are happy. So Aquinas defines will as the appetite of
the mind seeking the good; will moves us out into the world seeking
what is good for us, based on our rational understanding of it,
such as it is (e.g., Lizzie, four years old, eyeing a piece of
cake: "I want big!"). Once we think we know what is
good for us, we can then figure out how to attain it, act accordingly,
and enjoy the result.
"Reason makes a plan, and will tends to a goal ... resting
in a goal reached we call enjoyment."
(1a2ae. 12. 1)
Of course we are free to pursue many different goals, because
we can have an infinite number of ideas of what is good for us,
with some being authentically fulfilling and others not so much,
since we can be drawn to things that are bad for us, even if they
look quite attractive at the time.
As you recall, Aquinas sees evil basically not as something that
exists in its own right, but as something that ought to be there
but is not: a kind of non-being, a twistedness, a lack or a breakdown
of becoming. Likewise for actions.
"Actions are like things: that they exist is good as
far as it goes, but when they don't exist as fully as they should
that is bad."
(1a2ae. 18. 1)
Actions are considered well-formed when the object of the action
is good (e.g., furthers the flourishing of a life form) and
action itself is well-intentioned and appropriate to the circumstances.
According to Aquinas, the heart of morality is figuring out
choosing these well-formed actions that move us closer, day by
day, to that happy state of delighted self-awareness we call beatitudo.
Morality is not primarily about following rules, performing
renouncing desire, being nice, making a better society, monitoring
other people's behavior, or adhering to dogma. It is primarily
about using reason to figure out how to act in order to flourish.
But of course, humans are not completely (and sometimes hardly
ever) rational, so first Aquinas turns into a psychologist and
gives forth on two topics which fuel and shape our ongoing behavior:
passions and patterns of choice.
"The object of the will, that is the human appetite, is
the good without reserve, just as the object of the mind is the
truth without reserve."
(1a2ae. 2. 8)
Will and Grace ...
Will seeks the good; grace allows nature to be free to be itself.