So, there are certain aspects of Aquinas's view which are clear and others which are murky. First of all, I will go in to what is pretty clear and not (at least in the view of most, including myself) up for debate about his position.

1) Predestination is prior to the consideration of merits. For Aquinas, we are saved because of our merits (i.e. we die in the state of grace, avoid mortal sin, etc.). However, salvation is a free gift of God, therefore, it is ultimately up to God who is saved. That is basic Catholic thinking on the issue. But the question arises: does God determine those are saved conditionally (i.e. because of merits) or unconditionally (i.e. without considering future merits of individuals)? Aquinas argues that God predestines unconditionally, meaning that without considering future merits, God determines to elect certain people. On account of this decision, God by His omnipotence and His grace ensures that the elect act in such a way to attain eternal life. 

2) This may seem odd, how can God ensure that an elect individual acts rightly on the assumption that said individual have free will? Aquinas however would argue that God is the cause of every human choice. Now, this is not merely a Biblical conclusion but a philosophical one. According to St. Thomas, God is the first cause or creator of everything. Therefore, anything that exists, exists on account of God. The free choices of people are no exception. Therefore, God creates the free choices of individuals. This is how God can ensure that those whom He has chosen for heaven act meritoriously. There is no problem for Aquinas's view.

3) This raises the question: Does Aquinas think God is the cause of sin? No. Aquinas thinks God is the cause of the act of sin, and the choice to pursue some particular good when an agent sins. However, these are not what constitute the sin. According to Aquinas, the sin itself is both an activity (a choosing) and a defect, that is, something missing. Now, since defects aren't thinks but privations, they have no creative cause. They have a deficient cause. What this means is that the cause does not actively bring about something (as everything insofar as it exists according to Aquinas is good) but something which fails to act as it ought. And while it is true that in any sin it is a necessary precondition that God does not bring about the act or choice for virtue, it does not follow that God is the deficient cause of the sin. To be a deficient cause entails that the cause fails to act as it ought. However, since God has no telos, no moral obligations, or no purpose, we cannot say that if God fails to bring about my good actions He has failed to do as He ought. Therefore, God is not the deficient cause of the evil of sin although He is the creative cause of the goods present (e.g. the intellect's recognition of some good, the desire for that good, etc.)

4) Two colloaries follow: First, Aquinas cannot employ the Free Will Defense FWD (so popular today) to address moral evil because God could have prevented all moral evil without violating our freedom. Second, when God damns somebody, He does not actively create evil in them, but rather, He merely does not predestine that person to heaven. 

Here is where things get confusing: How exactly does God cause our choices while those choices remaining free? This question is both philosophical (how is divine causality to be reconciled with creaturely freedom and creaturely causality in general?) and theological (how is God's supernatural grace given to us via the sacraments compatible with our freely choosing?). Aquinas addresses these questions but it is not entirely clear what he is arguing for. Different interpreters throughout history have given different opinions. That said, the traditional "Dominican" Interpretation goes something like this:

1) God acts on creatures via a physical premotion. This basically means that things are instruments for God's causing. If God causes an apple to fall, it is because He physically premoves it to fall. What this means is that God, prior (not in the order of time but in the order of reason) to the apple falling decrees that the apple should fall. Then, in reality, the apple falls on account of this decree. This, the causes which move the apple to fall (the earth's gravity) become instruments of God's causality. In human choices, the same applies. The will becomes an instrument of God's causality. He decrees some choice should be made, and consequently, human wills follow God's decrees infallibly. 

2) What is said above applies to all choices and all created things in the natural order. However, what applies in the natural order also applies in the supernatural order. Therefore, grace, according to the Dominicans, moves people to freely choose the good and cannot fail. 


Hope this helps!

Camoden wrote:

Thanks for the reply. In some senses this sounds a decent bit like Calvinism, but not quite. Would you mine comparing and contrasting the differences between this and reformed theology?

Thanks in advance and may God bless you,

Cameron
 

Well, I am not expert in Calvinism and what Calvin himself actually wrote. So I speak somewhat tentatively. In any case, what I can say at first is that Calvin and Aquinas both are similar precisely because they are working with Augustine as a primary source. Augustine was one of the firsts to really articulate a view in which predestination takes place prior to consideration of our merits. In that sense, Calvin and Aquinas are Augustinians and insofar as they are faithful to Augustine, they are in agreement. 

Now, a lot of people would attribute "double predestination" to Calvin and this is certainly not what Aquinas or Augustine taught. In that sense, Calvin departs from these two. For Aquinas, God chooses who to predestination and consequently moves these people to perform good works. For a proponent of double predestination, God ALSO chooses who to damn and consequently moves these people to commit sins on account of this decree. So for Aquinas, the decision to damn someone is negative, i.e. prior to consideration of that person's sins, it is nothing other than the fact that God didn't predestine the person. However, for a proponent of double predestination, it is an additional decree to damn the person. (I realize that this distinction is somewhat obscure and perhaps a distinction without a difference...that is what the opponents of Aquinas's system argued).

Also, Calvin, I think takes a somewhat different view from Aquinas as to how God causes our actions. For Calvin, we are inevitably drawn towards choosing evil because we have evil desires unless God gives us grace. On account of giving us grace however, we are inevitably drawn towards the good. For Calvin, we are free as long as we choose from our own desires rather than external coercion. Our desires are sinful unless God gives us grace, in which case we always choose the good because it is what we want. So for God to cause our free choices, he just has to give us a stronger desire for one option over another. 

Aquinas however, doesn't argue like this. He doesn't say we always choose what we want the most. We are free in a stronger sense, i.e. in the sense that we can pursue any object as long as it is good in some sense, and nothing, not even our desires, can coerce us into choosing one way or another (if they did, we would lose our freedom). So for God to cause our choices, He can't just give us a desire. He has to move the will directly, in some different way. This is why the followers of St. Thomas call his doctrine one of PHYSICAL premotion. "Physical" in this context contrasts with moral influence. A moral influence is one in which someone is moved by motivating that person. For instance, if a mother offers a cookie to her young son for taking out the trash, she morally moves him to do so. Calvin's position involves God morally moving our wills. Aquinas's involves God working more directly. On this particular point, the Catholic Church does not have a particular stance. 

I'd add finally that there may be some difference between Aquinas and Calvin in terms of understanding (1) how free human beings are in fact (Calvin may be less optimistic than Aquinas) and (2) in understanding whether or not God's predestination is merely a result of the fall or not. For Aquinas, predestination would have existed even if Adam never fell because it is a consequence of the fact that God is the first cause, not merely a consequence of original sin. 

Hope this helps!