I think this quote is enough: I can see that St. Thomas really uses the sentences you mentioned in your last post. To understand him properly, it would be necessary, among other things, to compile all the texts where he wrote about the will and the intellect. …]
JuanFlorencio and Richea, we could be up all night talking about this. The magnitude of this topic is an entire year’s metaphysics course
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If you really want to understand Aquinas on the intellect and the will, you have to start (at a minimum) with
, I, q. 77Summa.
I can’t re-state the whole Summa in a few lines, here, so I will limit myself to the following. For Aquinas, a substance—especially a human or angelic substance; that is, a
person—is something
active. God has endowed it with a store of “act” or
enérgeia that is striving to get out and express itself, so to speak. Evidence of this is that humans and animals grow and develop, seeds become adult trees, and even stones seek their “end” (e.g., when they fall down).
However, unless the substance is God Himself, the substance is never identical with its operation. In fact, a “naked” created substance (one without accidents) cannot “do” anything directly; it can only “be.” (Naturally, there is no such thing as a naked substance; but if there
were one, it would be unable to perform any operation.) Hence, in order for a substance to produce an action, it must have a “power” that produces that action.
A couple of examples: I have a plastic cup in front of me. I can will to lift it up into the air as many times as I like, but it will not move until I take it in my hand and use my muscles to lift it up. My muscular system is an example of one of my
powers: the one that allows my body to move itself.
I have another power that enables me to imagine things: real things that I saw in the past, real things that are currently obstructed (like the back side of my computer), or even completely fictitious things (like the phoenix).
Moving on to properly spiritual activities, there is a power that enables me to know things (the intellect) and a different one that allows me to love things (my will).
There is an aspect here that is probably not obvious to the reader: in terms of Aristotle’s paradigm of act and potency, a power is always
in act, or actual, in one respect and
in potency, or potential, in a different respect. That is a universal and intrinsic condition of a power (except in God, whose powers are identical with Himself).
Look at the muscles, for example: they are in act inasmuch as they subsist (they are incomplete substances, like my hands), and inasmuch as they are ready, chemically and biologically, to contract when that is called for (or to relax, as the case may be).
However, in a different respect, they are also in potency:
right at this moment they are either relaxed or contracted, as the case may be, and so they are in the opposite state
in potency. And they are also in potency with respect to various stimuli: the motor nerves (which are ultimately directed by my will, in some cases), various reflexes, and so on.
With the intellect and the will, there is something similar. Both of these are properly speaking
qualities of the soul (qualities of the second species, if you want to be technical). They do not subsist like my muscles, but they inhere directly in me; they are the first accidents to proceed or emanate from my soul. They emanate
necessarily from the soul; there cannot be a human being who does not possess an intellect and a will. (So yes, even embryos and mentally handicapped people have intellects.)
Each of these powers is clearly in act: they exist (they are inherent in my soul); each of them has an active principle that enables them to function in response to what moves them (e.g., the agent intellect, and the will considered as appetite).
And yet, like all creaturely powers, they are also in potency. I think this is obvious in the case of the will: it can freely will or not will a particular good. That means that it is
in potency with respect to that good, and
in act once it actually makes its decision.
With the intellect… well, I don’t see how we can avoid saying that it is in potency to the things that it knows, before it knows them. I have never taken a course in quantum physics (but I would enjoy it); that means that my intellect is currently in potency with respect to the science of quantum physics.
The movement from potency to act is synonymous with change itself. So, if my intellect goes from “not knowing” to “knowing” it must go from potency to act. I don’t see how to avoid that conclusion.
Likewise, just as my body can, in a way, move itself, so too the intellect (through the agent intellect) can move itself. But that doesn’t take away the fact the intellect has to have something to work on: it needs data from the outside world in order to operate.