With the idea of providence, Aquinas is telling us that God not
only thinks us into existence, but thinks us into existence in
a particular way and for a particular purpose. He does this by
taking the idea of the goodness of actualization and applying
it not only to people, but to the universe as a whole.
Through the practice of science, we have discovered that in our
universe, in space and over huge periods of time, blobs of matter
have resolved themselves into stars and planets and such, and
on some of these planets (or on at least one), some of these blobs
of matter have turned into lifeforms. These lifeforms have taken
on stable and identifiable characteristics (e.g., genus, species)
and have gradually evolved in distinct ways, with increasing complexity
and order generating increasing consciousness. Now that's a pattern.
And a key attribute of this pattern is of course the fact that
it is increasing: the physical universe is driving itself towards
greater complexity and greater consciousness. Whatever creates
and sustains and evolves things in being does it in a precise
way (through ordered complexity) and in a precise direction (towards
consciousness). So if you imagine stepping back and looking at
this whole process of increasing complexity and consciousness
going on in space-time, you can get an inkling not only of what
Aquinas thinks God is like (as the mysterious source of it all)
but of where we are going. We are the vanguard (at least in our
neck of the universe) of the universe's drive to complexity and
consciousness, and Aquinas thinks that where we are aimed has
everything to do with that characteristic of God that Christians
call the Trinity.
"He creates every goodness in things, as we have already
shown. It is not only in the substance of created things that
goodness lies, but also in their being ordained to an end ...
. This good order existing in created things is itself part of
God's creation. Since he is the cause of things through his mind
... the divine mind must preconceive the whole pattern of things
moving to their end. This exemplar of things ordained to their
purpose is exactly what Providence is."