Joe, is this relevant to your question?
"nothing acts insofar as [secundum quod] it is in potency, but insofar as it is in act ... nothing prohibits this .. to be in potency in one respect [secundum aliquid] and in another respect in act, just as we see in natural things; for air is moist in actuality/act and dry in potentiality/potency, but earth the opposite. But this comparison is found between the intellectual soul and mental images [phantasmata]. For the intellectual soul has something in actuality, to which the mental image is in potency; and it is in potency toward something, which is found in actuality in the mental images."  SCG II.77.1-2

ETA: maybe also this:
Aristotle asks, it is the case that when something is simply hot or cold, it is in entelechy, and the other of the two is in potency? But when it’s not entirely one or the other but as hot/cold or cold/hot, and the mixing destroys the extremes, neither the matter nor each of the opposites is simply in act, ἐντελεχείᾳ, but in between, and in potency it’s either more cold or more hot and is so in some proportion like double or triple of the one as compared to the other? GenCorr II.7, 334b8-16.

Last edited by ficino (10/27/2017 4:51 am)

Joe, I'm not completely sure what problem you're trying to solve. So I don't know whether this will be to the point. A useful passage is Aristotle's Physics III.1, 200b26-28, 201a9-10:
“So there is something that is only in actuality [entelecheia], and something that is in potency and actuality—the one a particular ‘this’, the one a quantity, the one a quality, and the same way of the other categories of being … and in each genus, what is in actuality is distinguished from what is in potentiality … ”

For example, the unmoved mover is only in actuality. It moves the first sphere of heaven. The first sphere is both in potency and in actuality. It's in potency toward eternal circular motion, and that potency is actualized by the unmoved mover. But it is also in actuality because it is in motion. And it moves subordinate movers, so it moves them as it is in act itself.

As I understand it, nothing but the first unmoved mover is wholly actual in Aristotle. The unmoved mover is not in potentiality toward anything; it is fully actual. 

An example on the micro level is when I lift the bookend from my desk and move it to the shelf. With respect to THAT motion and its end, the bookend will be fully actual when it comes to rest on the shelf. (it won't be fully actual simpliciter.) While it is in motion from the desk to the shelf, it is in the process of being actualized as existing on the shelf, but it's not there yet, so it is both in potency and in act. Back when it was on my desk, it was in potency toward existing on the shelf.

If you're wondering, whether God can have any potentialities, under Thomism, the answer is no. There are various strategies for fitting in properties like God's free will.
 

Last edited by ficino (10/28/2017 5:03 am)

Hi Joe, to give an Aristotelian take on your example of an ice cube in lukewarm water would call for a reply of some length, so I won't go into it. To the question, " Now, would existing in a purely actual manner imply the absence of any active potentials? " the answer depends on the description under which you're framing "purely actual." A flame is heat fully actualized. If the primary bodies of fire in it go to their natural place in the cosmos, they will be at the top of the sublunary zone. Their existence with respect to the category of Place will be fully actualized. There will be many active potentials that cannot be predicated of fire, e.g. the power to cool things. And so on. So fire is not fully actual with respect to everything, not even w/ regard to Place. The movement of heavenly spheres and bodies brings fire particles back down to lower regions of the sublunary zone. Otherwise, given infinite time, the four simple bodies (fire, air, water, earth) would all be separated out into their natural places, one in a layer on top of the other, and there would be no generation of complex bodies anymore.

The Unmoved Mover is fully actual, but not with respect to every predicate. It is not fully actual as possessing scientific knowledge, episteme, for example, because its thought is pure intuition (however we translate "noesis"). And so on.

"does the argument from motion only get us to purely actual existence and not purely actual operation--or do the two go hand in hand?"

As I understand it, the argument from motion, Aquinas' First Way, gets us to a being that is the first cause of motion. It's about motion, i.e. change, not about contingent things' existence.

As to the way in which the unmoved mover moves things, Aquinas in the SCG says that the first unmoved mover moves by being the object of desire. It does not move by contact with what it moves; it is sought, to use a metaphor, by what it attracts. Aquinas refers to Aristotle's Metaphysics Lambda ch. 7 on this, where the first mover moves as a final cause, which is desired by the supreme sphere of the heaven. The supreme sphere seeks to imitate the unmoved mover as much as it can. It imitates it by being in motion in the simplest and best motion, eternal circular motion. Then it moves subordinate things, on down the ladder. It moves lower spheres by contact. The spheres don't move all even lower things by contact but they do move them by various influences and chains of movers.

I think this is a problem, because Aquinas is trying to adapt a system in which motion and movers and moved are eternal. Aristotle actually argues in Physics VIII to the first mover from what he feels he's established about the necessity that motion be eternal. As you know, Aquinas didn't think that creation was a doctrine that could be proved by natural reason. But for creation he needs a first efficient cause that jump-starts motion, so to speak, not merely one that elicits motion. Aristotle doesn't provide that kind of first mover, as Aquinas understands Aristotle.

Enrico Berti and others argue that actually, the first mover in Metaphysics Lambda is an efficient cause as well as a final cause. But Aquinas did not have that take on Aristotle.

So far I have not seen a robust explanation of how Aquinas' God does not undergo change. I should think God's capacity to be a cause is actualized at creation. Aquinas tries to deal with this by insisting that creation is not in time, so there is no transition period that God goes through. Still, there is a state of affairs under which God is creator, and another state of affairs under which God is not creator. God's relations are different. There may be an adequate way of saving God from the "accusation" of actualizing His own potentiality, but I haven't come across it yet. Please let me know if you know more about this problem.

It seems to me that every time I read or listen to Edward Feser explaining the First Way, he winds up converting an argument from and for motion into an argument about necessary existence. In order to explain per se ordered series of movers in a post-Newtonian world, Feser will push the chain of movers to the point where he'll say things like "but the desk has to be sustained in being." Now he's not talking motion anymore. So I think so far in my acquaintance with his work, that Feser's treatments of some of the Ways collapse into the argument from necessary vs. contingent being. So he might as well just work from De Esse et Essentia and leave it at that.

I'm ready to be corrected if I'm misunderstanding Feser.

Last edited by ficino (10/28/2017 6:17 am)