Thomas Aquinas: Biography, Faith, Reason, and God
Biography of Thomas Aquinas
Thomas Aquinas was born in Roccasecca Castle, the son of the Count of Aquino. He entered the Dominican Order in Naples and later joined the faculty of theology in Paris, where he became a disciple of Albertus Magnus. He taught and wrote in various cities in France and Italy. He returned to Paris and was summoned by the Pope to the Second Council of Lyons. He fell ill during the journey and died at the Cistercian abbey of Fossanova.
Faith and Reason According to Aquinas
Aquinas distinguished between philosophy and theology, reason and faith. He believed there is revealed truth, accessible only through faith, and natural truth, accessible through reason. The articles of faith, he argued, can only be believed by faith. Aquinas defined faith as an act of understanding, with the will moved by God to assent through grace. Articles of faith are inaccessible to reason, and that is why theology is concerned with their study. Reason investigates self-evident truths. Aquinas sought to find the correlation between faith and reason, hence the notion that philosophy is the handmaiden of theology. He invalidated the theory of double truth, asserting that truths arrived at by reason do not contradict the truths of faith.
The Need for Proof of God’s Existence
Why is it necessary to demonstrate that God exists if it is something believed by faith? Aquinas addressed Saint Anselm’s ontological argument, which defined God as “that than which nothing greater can be conceived” and established the necessity of God’s existence a priori (propter quid, as St. Thomas called it). Aquinas argued this demonstration is not valid because it starts from the essence of God. While God *is* existence, the essence of the subject is not clear to us. Therefore, for a demonstration to be valid, it must start from the effect and ascend to the cause. Thus, the demonstration must be a posteriori, from effect to cause.
Aquinas’s Five Ways (Arguments for God’s Existence)
First Way: Argument from Motion
It is evident to our senses that things in the world are in motion. Anything that is moved is moved by another. It is impossible for something to be both mover and moved in the same respect. This chain of movers cannot go on to infinity. Therefore, it is necessary to arrive at a first unmoved mover, and this is what everyone understands to be God.
Second Way: Argument from Efficient Cause
We find in the sensible world an order of efficient causes. Nothing can be the efficient cause of itself, for then it would be prior to itself, which is impossible. Therefore, it is necessary to admit a first efficient cause, to which everyone gives the name of God.
Third Way: Argument from Contingency
We find in nature things that are possible to be and not to be (contingent beings). It is impossible for these always to exist, for that which can not-be at some time is not. Therefore, not all beings are merely possible. There must exist something the existence of which is necessary. This necessary being either has its necessity caused by another or not. If not, then it is the uncaused cause of necessity, and this all men speak of as God.
Fourth Way: Argument from Gradation of Being
Among beings, there are some more and some less good, true, noble, and so on. But “more” and “less” are predicated of different things according as they resemble in their different ways something which is the maximum. Therefore, there is something which is truest, best, noblest, and, consequently, most fully in being. This we call God.
Fifth Way: Argument from Design (Teleological Argument)
We see that things which lack intelligence, such as natural bodies, act for an end. They do this not fortuitously, but designedly. Whatever lacks intelligence cannot move towards an end, unless it be directed by some being endowed with knowledge and intelligence. Therefore, some intelligent being exists by whom all natural things are directed to their end; and this being we call God.
Conclusions
There is a clear Aristotelian influence in the first, second, and fifth ways. The fourth way shows Neoplatonic influences. Aquinas’s arguments are influenced by Latin Averroism’s distinction between possible beings (created, contingent beings) and the necessary being.