Thomas Aquinas lived in the 13^th century within the theological empire of Christendom during the height of Papal power. He attempted to integrate the pagan classical philosophers (mainly Aristotle) with the teachings of Christianity. This is not straightforward. Philosophy provides a route to understanding through rational thought. Religion emphasises faith and revelation, and places limits on human understanding. Aquinas compromised by saying that human reason is a divine gift that should be used, but only within its proper sphere.

Papal vs. Secular Power

Two theories of authority existed in the Christian world; the descending view where rulers receive absolute power from God, and the ascending where they are granted power by the people. The descending view was more common, and Christian subjects had a duty to be obedient. However Augustine’s very narrow view of the circumstances for disobedience, appropriate during a time of Empire, were relaxed for the Medieval world of weaker states. In extreme cases if a ruler does not govern well then they have forfeited their right to rule. It was the Pope who determined when this was the case by Excommunicating the ruler. Given this belief in the divine source of authority and obligation to obedience, revolutions did not generally occur in the Medieval world, and constitutional methods of removing rulers were not considered.

The competing authority of Popes and secular rulers created huge opportunity for conflict, the ultimate question being who had the greater authority? The doctrine of the two swords was an attempt to answer this question. It said that both Pope and an Emperor had absolute authority from God, but in different spheres, and both were responsible for supporting the other’s authority. The church would obey secular law, but would have ultimate authority in matters of faith. The doctrine was rejected in the Eastern Roman Empire where the Emperor had sole absolute authority, but secured a tenuous peace between the Papacy and secular western rulers through most of the Medieval period.

Aquinas’ views on papal power are moderate. The pope and clergy have immunity from taxation and from secular law courts, but can only intervene in political matters in extreme cases. This is not the separation of church and state as Aquinas takes it for granted that the two overlap. The state needs the moral guidance of the church, and the church needs the earthly assistance of the state. Non-believers should be gently coerced to the true faith and prevented from subverting the faith of believers, but that is all. Non-Christian rulers should be obeyed as long as they follow their earthly duty to rule justly, and do not require Christians to break with Christian teaching. Heretics are a far more severe matter. They are in breach of their obligations to God and have committed a mortal sin. If unrepentant they must be executed.    

Natural & Divine Law

The idea of natural law, i.e. the notion of law that is consistent with our better nature and rationally right, was common in the classical world. The Christian view of descending divine power led to the view that the King’s word is law. However, if people had a Christian obligation to obey their ruler, the ruler’s laws had a similar obligation to be consistent with Christian morality. If they did not, the people could passively disobey. This represents a more confident  Christian world than that of Augustine’s, who believed humans incapable knowing right from wrong.

Aquinas discussed the relationship between natural and divine law. For example, in Aristotle’s view some people are naturally slaves, however God gave the world to man in common, so there can be no natural slavery under divine law. Both believed in a divine natural order of things, but Aquinas attributes the divine order to the will of God. Ever since our fall into sin we need natural law to make us live virtuously. Like Augustine, Aquinas believed that a sinful nature makes a coercive state necessary and the search for the perfect state on earth hopeless. But Aquinas is less pessimistic, believing like Aristotle that a political system is needed to aspire as close as possible to heavenly perfection. Like Aristotle he also believes that a politeia is the best practicable state, but believes monarchy rather than Aristocracy to be the best, on the grounds of efficiency. On the same ground tyranny is worse than democracy; tyranny is a more efficient and therefore damaging form of misrule. However Aristotle’s concern for achieving balance to avoid revolution is gone. The aim is to enforce Christian morality. Nevertheless, Aquinas’ morality points him towards limited or constitutional monarchy. It is not the personal will of the monarch that makes laws but the monarch’s ability to represent the will of the people. This was on the progressive end of contemporary thought. An ineffective monarch losses the moral right to rule, but tryannicide can only be done by the people or someone who represents the people. The murder of Caesar by a handful of senators would not qualify.

Property often highlights inequality and was an ethical issue during Aquinas’ time. He argued that God has sole sovereignty over the world, but gave mankind the world to use and improve, and gave us dominion over inferior creatures. Therefore we may appropriate what is useful for human life. He uses Aristotle’s argument that private property is better cared for and clarity of ownership provides stability. However, the distribution of property should be for the common good, and that theft of excess property is justifiable in extreme cases such as to avoid starvation. War can also be justified and lawful in the right circumstances. It must be declared by a person authorised to do so, it must be fought in self defence (which includes a pre-emptive strike, recovering territory unjustly taken), and it must be fought with the right intention to restore peace and punish the wicked.

If you are interested in finding out more about this topic, I strongly recommend getting a copy of Alan Ryan’s ‘On Politics’, which this blog is predominantly based on. Here are a few links you can use to find it:

https://www.penguin.co.uk/books/254/25400/on-politics/9780140285185.html

https://www.goodreads.com/book/show/13812171-on-politics

https://play.google.com/store/books/details/Alan_Ryan_On_Politics?id=w68kEZxDO3IC