With Thomas Aquinas we have the enfolding of the Aristotelean system into the Augustinian. We have the enfolding of a system that holds that justice and rationality requiring education in virtue into system that posits that the demands of justice are in some way self-evident to all human beings, even in a fallen state and that our ability to act justly and reason properly depends not upon our own abilities but primarily on the grace of God. Thomas’ solution is to hold that our natural-yet-fallen understanding of justice precedes and presupposes our graced-education into virtue which is only possible as our will is transformed from a state of inability to will the good to the ability with God’s help to will the good. God’s law is the basis of justice, but there is no justice without virtue, and no virtue without grace, and it is grace that transforms our wills and minds so that acting faithfully and acting rationally are one in the same thing.
Thomas held that the natural law is discoverable by human reason apart from any special infusion of grace. Though it was discoverable it was impossible to obey apart from grace, therefore justice and rationality require an infusion of grace which leads to the presence of the cardinal virtue of charity. With our minds and wills shaped by charity we will develop prudence, the practical intelligence whereby we understand what charity demands in a given situation. Charity cannot be acquired by education it is a gift of God’s grace through the Holy Spirit.
The good toward which all human actions aim for Thomas is the beatific vision of God. This is the good toward which all of our graced actions and faith-ed thoughts guide us. Aristotle could conceive of no such telos. And because of this for Thomas Aristotle’s who system is defective because it is ordering its goods toward the wrong goal.
What sets Thomas apart from any other moral philosopher up to that point was the scope and scale of his project. The numbers of topics he covered was massive and the systematic nature in which he treated them was without peer. Thomas was truly a systematic thinker whose system shaped an entire world-view, one that is completely at odds with the modern world-view at several points. One is that Thomas’ system has no place for the endless acquisitiveness of free-market capitalism which is all about amassing and reinvesting surplus capital. For Thomas such unending surpluses are a sign that justice isn’t being served because one is demanding more for goods or labor than is just which is an exploitation of the other. In a Thomist economy there is such thing as a just distribution of goods and a restraint upon the amount of wealth that one can amass. Thomist justice is also counter to our adversarial court system. For Thomas it is unjust for one to defend someone they believe to be guilty. Our legal system requires it. Thomas held that unjust laws don’t have to be obeyed and as governments approach tyranny they lose all claim to our obedience.
But what sets Thomas most apart is his assertion that the first demand of justice is the worship that we owe God. A social order cannot be justice if it does not render to God what is His due. This is especially striking to those of us raised in a country where the relationship of the state to religion is conceived of as neutral, not opposing or supporting such worship. For Thomas that a society such as ours could be called just or rational would be beyond his comprehension.