Aquinas was famously inspired by the works of Aristotle. Aristotle had a rather odd idea, to modern ears, of what politics is about. Aristotle tells us:
“The end of politics is the best of ends; and the main concern of politics is to engender a certain character in the citizens and to make them good and disposed to perform noble actions.”-- Ethica Nicomachea, I.9, 1099b30.
Aristotle believed that virtue is the highest good--that only virtue truly leads to happiness. In order to seek the good of its citizens, then, Aristotle believed that the state should guide us to virtue. Taken at face value, Aristotle's dictum can lead in some very dangerous, totalitarian directions. After the horrors of the twentieth century, we certainly don't want some fascist or communist dictatorship micromanaging our lives, trying to remold us through great misery and pain into the state's vision of virtue. And yet we Catholics do find Aquinas agreeing with Aristotle.
(Before reading what Aquinas has to say, a word about how he writes. It can be hard on the modern reader, but I think his arguments need to be read in full if we are to grapple with them. The first thing to keep in mind is that Aquinas writes in outline form. He begins his consideration of each philosophical question by imagining objections to his own position. Only after listing these objections does he "answer" with his own viewpoint, and then explain why the objections are wrong.)
Here is Aquinas agreeing (as usual) with Aristotle, whom Aquinas always deferentially refers to as "The Philosopher":
-- Summa Theologica, I-II, Q. 92, art. 1.
Article 1. Whether an effect of law is to make men good?
Objection 1. It seems that it is not an effect of law to make men good. For men are good through virtue, since virtue, as stated in Ethic. ii, 6 is "that which makes its subject good." But virtue is in man from God alone, because He it is Who "works it in us without us," as we stated above (Question 55, Article 4) in giving the definition of virtue. Therefore the law does not make men good.
Objection 2. Further, Law does not profit a man unless he obeys it. But the very fact that a man obeys a law is due to his being good. Therefore in man goodness is presupposed to the law. Therefore the law does not make men good.
Objection 3. Further, Law is ordained to the common good, as stated above (Question 90, Article 2). But some behave well in things regarding the community, who behave ill in things regarding themselves. Therefore it is not the business of the law to make men good.
Objection 4. Further, some laws are tyrannical, as the Philosopher says (Polit. iii, 6). But a tyrant does not intend the good of his subjects, but considers only his own profit. Therefore law does not make men good.
On the contrary, The Philosopher says (Ethic. ii, 1) that the "intention of every lawgiver is to make good citizens."
I answer that, as stated above (90, 1, ad 2; A3,4), a law is nothing else than a dictate of reason in the ruler by whom his subjects are governed. Now the virtue of any subordinate thing consists in its being well subordinated to that by which it is regulated: thus we see that the virtue of the irascible and concupiscible faculties consists in their being obedient to reason; and accordingly "the virtue of every subject consists in his being well subjected to his ruler," as the Philosopher says (Polit. i). But every law aims at being obeyed by those who are subject to it. Consequently it is evident that the proper effect of law is to lead its subjects to their proper virtue: and since virtue is "that which makes its subject good," it follows that the proper effect of law is to make those to whom it is given, good, either simply or in some particular respect. For if the intention of the lawgiver is fixed on true good, which is the common good regulated according to Divine justice, it follows that the effect of the law is to make men good simply. If, however, the intention of the lawgiver is fixed on that which is not simply good, but useful or pleasurable to himself, or in opposition to Divine justice; then the law does not make men good simply, but in respect to that particular government. In this way good is found even in things that are bad of themselves: thus a man is called a good robber, because he works in a way that is adapted to his end.
Reply to Objection 1. Virtue is twofold, as explained above (Question 63, Article 2), viz. acquired and infused. Now the fact of being accustomed to an action contributes to both, but in different ways; for it causes the acquired virtue; while it disposes to infused virtue, and preserves and fosters it when it already exists. And since law is given for the purpose of directing human acts; as far as human acts conduce to virtue, so far does law make men good. Wherefore the Philosopher says in the second book of the Politics (Ethic. ii) that "lawgivers make men good by habituating them to good works."
Reply to Objection 2. It is not always through perfect goodness of virtue that one obeys the law, but sometimes it is through fear of punishment, and sometimes from the mere dictates of reason, which is a beginning of virtue, as stated above (Question 63, Article 1).
Reply to Objection 3. The goodness of any part is considered in comparison with the whole; hence Augustine says (Confess. iii) that "unseemly is the part that harmonizes not with the whole." Since then every man is a part of the state, it is impossible that a man be good, unless he be well proportionate to the common good: nor can the whole be well consistent unless its parts be proportionate to it. Consequently the common good of the state cannot flourish, unless the citizens be virtuous, at least those whose business it is to govern. But it is enough for the good of the community, that the other citizens be so far virtuous that they obey the commands of their rulers. Hence the Philosopher says (Polit. ii, 2) that "the virtue of a sovereign is the same as that of a good man, but the virtue of any common citizen is not the same as that of a good man."
Reply to Objection 4. A tyrannical law, through not being according to reason, is not a law, absolutely speaking, but rather a perversion of law; and yet in so far as it is something in the nature of a law, it aims at the citizens' being good. For all it has in the nature of a law consists in its being an ordinance made by a superior to his subjects, and aims at being obeyed by them, which is to make them good, not simply, but with respect to that particular government.
Aquinas endorses the idea that it is legitimate for the state to lead us to virtue. Further, Aquinas tells us that the state may legitimately compel us to virtue:
Article 1. Whether it was useful for laws to be framed by men?-- Summa Theologica, I-II, Q. 95, art. 1.
Objection 1. It would seem that it was not useful for laws to be framed by men. Because the purpose of every law is that man be made good thereby, as stated above (Question 92, Article 1). But men are more to be induced to be good willingly by means of admonitions, than against their will, by means of laws. Therefore there was no need to frame laws....
On the contrary, Isidore says (Etym. v, 20): "Laws were made that in fear thereof human audacity might be held in check, that innocence might be safeguarded in the midst of wickedness, and that the dread of punishment might prevent the wicked from doing harm." But these things are most necessary to mankind. Therefore it was necessary that human laws should be made.
I answer that, As stated above (63, 1; 94, 3), man has a natural aptitude for virtue; but the perfection of virtue must be acquired by man by means of some kind of training. Thus we observe that man is helped by industry in his necessities, for instance, in food and clothing. Certain beginnings of these he has from nature, viz. his reason and his hands; but he has not the full complement, as other animals have, to whom nature has given sufficiency of clothing and food. Now it is difficult to see how man could suffice for himself in the matter of this training: since the perfection of virtue consists chiefly in withdrawing man from undue pleasures, to which above all man is inclined, and especially the young, who are more capable of being trained. Consequently a man needs to receive this training from another, whereby to arrive at the perfection of virtue. And as to those young people who are inclined to acts of virtue, by their good natural disposition, or by custom, or rather by the gift of God, paternal training suffices, which is by admonitions. But since some are found to be depraved, and prone to vice, and not easily amenable to words, it was necessary for such to be restrained from evil by force and fear, in order that, at least, they might desist from evil-doing, and leave others in peace, and that they themselves, by being habituated in this way, might be brought to do willingly what hitherto they did from fear, and thus become virtuous. Now this kind of training, which compels through fear of punishment, is the discipline of laws. Therefore in order that man might have peace and virtue, it was necessary for laws to be framed: for, as the Philosopher says (Polit. i, 2), "as man is the most noble of animals if he be perfect in virtue, so is he the lowest of all, if he be severed from law and righteousness"; because man can use his reason to devise means of satisfying his lusts and evil passions, which other animals are unable to do.
Reply to Objection 1. Men who are well disposed are led willingly to virtue by being admonished better than by coercion: but men who are evilly disposed are not led to virtue unless they are compelled.
So does this mean that human law should control every aspect of our lives? Should Catholics seek a totalitarian state that micromanages us into virtue? No.
Article 2. Whether it belongs to the human law to repress all vices?-- Summa Theologica, I-II, Q. 96, art. 2.
Objection 1. It would seem that it belongs to human law to repress all vices. For Isidore says (Etym. v, 20) that "laws were made in order that, in fear thereof, man's audacity might be held in check." But it would not be held in check sufficiently, unless all evils were repressed by law. Therefore human laws should repress all evils.
Objection 2. Further, the intention of the lawgiver is to make the citizens virtuous. But a man cannot be virtuous unless he forbear from all kinds of vice. Therefore it belongs to human law to repress all vices.
Objection 3. Further, human law is derived from the natural law, as stated above (Question 95, Article 2). But all vices are contrary to the law of nature. Therefore human law should repress all vices.
On the contrary, We read in De Lib. Arb. i, 5: "It seems to me that the law which is written for the governing of the people rightly permits these things, and that Divine providence punishes them." But Divine providence punishes nothing but vices. Therefore human law rightly allows some vices, by not repressing them.
I answer that, As stated above (90, A1,2), law is framed as a rule or measure of human acts. Now a measure should be homogeneous with that which it measures, as stated in Metaph. x, text. 3,4, since different things are measured by different measures. Wherefore laws imposed on men should also be in keeping with their condition, for, as Isidore says (Etym. v, 21), law should be "possible both according to nature, and according to the customs of the country." Now possibility or faculty of action is due to an interior habit or disposition: since the same thing is not possible to one who has not a virtuous habit, as is possible to one who has. Thus the same is not possible to a child as to a full-grown man: for which reason the law for children is not the same as for adults, since many things are permitted to children, which in an adult are punished by law or at any rate are open to blame. In like manner many things are permissible to men not perfect in virtue, which would be intolerable in a virtuous man.
Now human law is framed for a number of human beings, the majority of whom are not perfect in virtue. Wherefore human laws do not forbid all vices, from which the virtuous abstain, but only the more grievous vices, from which it is possible for the majority to abstain; and chiefly those that are to the hurt of others, without the prohibition of which human society could not be maintained: thus human law prohibits murder, theft and such like.
Reply to Objection 1. Audacity seems to refer to the assailing of others. Consequently it belongs to those sins chiefly whereby one's neighbor is injured: and these sins are forbidden by human law, as stated.
Reply to Objection 2. The purpose of human law is to lead men to virtue, not suddenly, but gradually. Wherefore it does not lay upon the multitude of imperfect men the burdens of those who are already virtuous, viz. that they should abstain from all evil. Otherwise these imperfect ones, being unable to bear such precepts, would break out into yet greater evils: thus it is written (Psalm 30:33): "He that violently bloweth his nose, bringeth out blood"; and (Matthew 9:17) that if "new wine," i.e. precepts of a perfect life, "is put into old bottles," i.e. into imperfect men, "the bottles break, and the wine runneth out," i.e. the precepts are despised, and those men, from contempt, break into evils worse still.
Reply to Objection 3. The natural law is a participation in us of the eternal law: while human law falls short of the eternal law. Now Augustine says (De Lib. Arb. i, 5): "The law which is framed for the government of states, allows and leaves unpunished many things that are punished by Divine providence. Nor, if this law does not attempt to do everything, is this a reason why it should be blamed for what it does." Wherefore, too, human law does not prohibit everything that is forbidden by the natural law.
Aquinas' words above in the "Reply to Objection 2" are the core of this post, and of much of my own attempt at political thought. The state may legitimately lead us to virtue, but in prudence, it must lead us gradually. This will often mean allowing us to behave viciously (i.e., with vice), if we are unable to bear compulsion to greater virtue. The core insight of a Burkean conservatism is that human nature is not amenable to utopian schemes to refashion it with the brutal tools of the state. Modern liberals, conservatives, and libertarians, all Whigs in different ways, draw from this the lesson that we have a right to be let alone by the state. While conceding that it is often imprudent for the state to attempt to mold us to virtue, Aquinas does not concede, however, a right to act as viciously as we please without state interference:
Article 3. Whether human law prescribes acts of all the virtues?-- Summa Theologica, I-II, Q. 96, art. 3.
Objection 1. It would seem that human law does not prescribe acts of all the virtues. For vicious acts are contrary to acts of virtue. But human law does not prohibit all vices, as stated above (Article 2). Therefore neither does it prescribe all acts of virtue.
Objection 2. Further, a virtuous act proceeds from a virtue. But virtue is the end of law; so that whatever is from a virtue, cannot come under a precept of law. Therefore human law does not prescribe all acts of virtue.
Objection 3. Further, law is ordained to the common good, as stated above (Question 90, Article 2). But some acts of virtue are ordained, not to the common good, but to private good. Therefore the law does not prescribe all acts of virtue.
On the contrary, The Philosopher says (Ethic. v, 1) that the law "prescribes the performance of the acts of a brave man . . . and the acts of the temperate man . . . and the acts of the meek man: and in like manner as regards the other virtues and vices, prescribing the former, forbidding the latter."
I answer that, The species of virtues are distinguished by their objects, as explained above (54, 2; 60, 1; 62, 2). Now all the objects of virtues can be referred either to the private good of an individual, or to the common good of the multitude: thus matters of fortitude may be achieved either for the safety of the state, or for upholding the rights of a friend, and in like manner with the other virtues. But law, as stated above (Question 90, Article 2) is ordained to the common good. Wherefore there is no virtue whose acts cannot be prescribed by the law. Nevertheless human law does not prescribe concerning all the acts of every virtue: but only in regard to those that are ordainable to the common good--either immediately, as when certain things are done directly for the common good--or mediately, as when a lawgiver prescribes certain things pertaining to good order, whereby the citizens are directed in the upholding of the common good of justice and peace.
Reply to Objection 1. Human law does not forbid all vicious acts, by the obligation of a precept, as neither does it prescribe all acts of virtue. But it forbids certain acts of each vice, just as it prescribes some acts of each virtue.
Reply to Objection 2. An act is said to be an act of virtue in two ways. First, from the fact that a man does something virtuous; thus the act of justice is to do what is right, and an act of fortitude is to do brave things: and in this way law prescribes certain acts of virtue. Secondly an act of virtue is when a man does a virtuous thing in a way in which a virtuous man does it. Such an act always proceeds from virtue: and it does not come under a precept of law, but is the end at which every lawgiver aims.
Reply to Objection 3. There is no virtue whose act is not ordainable to the common good, as stated above, either mediately or immediately.
Aquinas' vision tempers Aristotle by giving us the important Burkean insight that people are not always reformable by the state, and the state will do more harm than good if it fails to recognize this. However, Aquinas tempers modern Whiggish liberal and libertarian philosophies because he does not speak in terms of the state's leaving us alone as a matter of our "rights," rather than of political prudence.
(Which is not to say that people do not have rights vis-à-vis the state. For example, in the 1965 declaration Dignitatis Humanae, the council fathers of Vatican II endorse and defend the human right to the free exercise of religion.)
In contrast to modern thinkers, Aquinas agrees with Aristotle that the state may and should legitimately lead us to virtue. Where Aquinas saves us from totalitarianism, however, is tempering this truth with the recognition that sometimes the best way to lead us to virtue is indeed to leave us alone. Totalitarian micromanagement of individual lives by the state does not lead to virtue. Instead, it "bringeth out blood."