X Close Menu





Thomas Aquinas was born at Roccasecca in Italy. His father was Count Landulf of Aquino (thus the name Aquinas). He joined the Dominican order of monks in 1242 against his family’s wishes. His father sent his brothers to kidnap him in an attempt to “deprogram” the young man. They even tried, unsuccessfully, to lure him into sin with a prostitute, thinking that he would then regard himself as unfit for the ministry! Aquinas was held captive by his family for two years. Upon his release he immediately returned to the order, and began his studies at the university in Paris. He spent a dozen years teaching in Italy until he was recalled to Paris in 1269. He encountered opposition there and in 1272 was sent to Naples to establish a dominican school. He died two years later on March 7, 1274, not yet fifty years old.


It is said that shortly after his death, miracles began to occur near the place where his body was laid. Monks at the Cistercian abbey at Fosanova, where Thomas was buried, feared that some might steal the body. They exhumed the corpse and cut off its head, placing the latter in a secret corner of the chapel. Mutilations continued for almost fifty years until all that remained were the bones. These were finally moved to the Dominican monastery at Toulouse where they remain to this day.


His teacher, Albert Magnus (Albert the Great) is supposed to have said in class: “We call this lad a dumb ox, but I tell you that the whole world is going to hear his bellowing.” The nickname (“dumb ox”) stayed with him throughout life. His two most notable works are the multivolume Summa contra Gentiles (a defense of Christianity against Muslim scholars in Spain and North Africa) and Summa Theologica (his systematic theology, described by Peter Kreeft as “certainly the greatest, most ambitious, most rational book of theology ever written”). He is known primarily for:


·His doctrine of natural theology, according to which rudimentary knowledge about God and the human soul is attainable by reason apart from any special, gracious, supernatural or revelatory activity of God. Thus even a non-Christian (such as Aristotle) could follow a purely natural path to the knowledge of God. However, when it comes to the doctrine of the Trinity or the incarnation or the nature of Christ’s redemptive sacrifice or the efficacy of the sacraments, we are dependent on divine revelation.


·His doctrine of the five ways or five proofs for the existence of God (see below).


·His doctrine of salvation, which to the surprise of most Protestants, was remarkably Augustinian and monergistic (he did, however, maintain the necessity of church sacraments for progress in the Christian life).


·His concept of analogy as the way of knowing God. Two words are said to be univocal if they are used in an identical sense (in the assertions, “Al Gore was the Democratic candidate” and “George Bush was the Republican candidate” the word “candidate” is used in the same sense, i.e., univocally). Two words are said to be equivocal if they are used in an entirely different sense (in the assertions, “That animal is a rat” and “That man is a rat” the word “rat” is used in two different senses, i.e., equivocally). Two words are used analogically if their respective meanings are in some sense both similar and different (in the two sentences, “My home is in Chicago” and “A gopher’s home is underground” the word “home” is partly the same in both and partly different). “According to Thomas, no words that humans apply to God can be used in a univocal sense. While God is transcendent and infinite, the categories by means of which humans attempt to describe him are drawn from our human experience of the imperfect world” (Ronald Nash, Life’s Ultimate Questions [Zondervan] 178). Therefore, whatever words we use to describe God are, at best, analogically true of him. [Note: It is important to point out that regardless of what we say concerning God there must be a univocal element present. As one critic of Aquinas has pointed out, “all the analogies of common speech have a univocal basis. . . . Now matter how complicated, or what type of analogy, an examination must discover some univocal element. The two terms [in an analogy, such as “God and Solomon are both wise”] must be like each other in some respect. If there were no likeness or similarity of any sort, there could be no analogy. And the point of likeness can be designated by a simple univocal term of phrase” (Gordon Clark, A Christian View of Men and Things, 311).]


Aquinas was canonized as a saint in 1323 and given the title Angelic Doctor. Pope Pius V gave him the title Universal Doctor of the Church in 1567 during the Council of Trent (during the council a copy of the Summa Theologica was placed on the altar “in second place only to the Bible” [Kreeft, A Shorter Summa, 15]). Pope Leo XIII made Aquinas’s theology the norm for Catholic theology in his encyclical letter of 1879 called Aeterni Patris (in it he exhorted all Catholic teachers to “restore the golden wisdom of St. Thomas . . . and let them clearly point out its solidity and excellence above all other teaching”).


Lest one regard Thomas as a coldly intellectual theologian, devoid of godly passion, consider the story told of him by one young man. During his final years at Naples, Thomas was working on the conclusion of the Summa (which he never concluded!). A young man entered the room to find Thomas deep in prayer, allegedly floating above the ground (!). A voice was heard coming from the crucifix which Thomas held in hand: “Thomas, you have written well of me. What reward can I give you for all your labours?” To which Thomas replied: “Nothing, Lord. Nothing, but You.” Some time later, on Dec. 6th, 1273, he had an experience during Mass that so profoundly affected him that he wrote nothing more. When urged by his friends to complete the Summa, he replied: “I cannot, for compared with what I have seen and what has been revealed to me [evidently, during the Mass], everything I have written seems like straw.”


A. The Five Ways


Thomas advocated what has come to be known as the cosmological argument for the existence of God, according to which one may argue from the existence of the world to the existence of an uncaused, First Cause, namely, God. Related to this is the teleological argument, according to which one may argue from order and design in the world to the existence of an Orderer or Designer. The Five Ways include:


·The argument from motion or change

·The argument from causation

·The argument from contingency of being

·The argument from gradation

·The argument from design


(1) Consider the following, taken from his first argument from motion or change:


“The first and most obvious proof is that which is based on change. It is certain and evident to the senses that some things in this world are in a process of change. But anything in a process of change is being changed by something else. For although things which are changing possess the potential for [the actuality] towards which they move, they do not yet have it, whereas that which causes the change possesses it in actuality. To cause change is nothing more than to transform potentiality into actuality, but to transform potentiality into actuality can only be done by something in which the actuality already exists. For example, fire, which is hot in actuality, causes wood, which is hot in potentiality, to become hot in actuality, and thereby it brings about a change in the nature of the wood. Now it is impossible for something to be actually and potentially the same thing at the same time. It may, however, be actually one thing and potentially something else. For example, something which is actually hot cannot be potentially hot at the same time. It can, however, be potentially cold. So it follows from this that something which is changing cannot itself be the cause of the change and the result of the change at the same time: a thing cannot change itself. Anything that is changing, therefore, is being changed by something else. But if the thing that is causing the change is itself being changed, it is itself being changed by a second something, and this, in turn, by a third. But we cannot go on forever with this process, for if we do, there will be no First Changer to cause the first change and therefore no subsequent causes [to cause the subsequent changes]. A second cause will not produce change unless it is acted upon by a first cause. A stick, for example, will not move or change anything else unless it is itself first moved by the hand. It follows, therefore, that one is bound to arrive at some first cause of change which is not itself changed by anything, and this is what everybody understands by God” (Summa Theologica, Part I, Question Two, Article Three).


(2) Aquinas appeals, secondly, to the nature of an efficient cause:


“We find that there is a sequence of efficient causes in sensible things. But we do not find that anything is the efficient cause of itself. Nor is this possible, for the thing would then be prior to itself, which is impossible. But neither can the sequence of efficient causes be infinite, for in every sequence the first efficient cause is the cause of an intermediate cause, and an intermediate cause is the cause of the ultimate cause, whether the intermediate causes be many, or only one. Now if a cause is removed, its effect is removed. Hence if there were no first efficient cause, there would be no ultimate cause, and no intermediate cause. But if the regress of efficient causes were infinite, there would be no first efficient cause. There would consequently be no ultimate effect, and no intermediate causes. But this is plainly false. We are therefore bound to suppose that there is a first efficient cause. And all men call this God” (ibid.).


(3) His third argument is based on the nature of possibility and necessity. He argues that whereas some things may either exist or not exist, there must be some thing that must exist:


“Now everything which is necessary either derives its necessity from elsewhere, or does not. But we cannot go on to infinity with necessary things which have a cause of their necessity, any more than with efficient causes, as we proved. We are therefore bound to suppose something necessary in itself, which does not owe its necessity to anything else, but which is the cause of the necessity of other things. And all men call this God” (ibid.).


(4) The fourth way of arguing for God’s existence is


“from the degrees that occur in things, which are found to be more and less good, true, noble, and so on. Things are said to be more and less because they approximate in different degrees to that which is greatest. A thing is the more hot the more it approximates to that which is hottest. There is therefore something which is the truest, the best, and the noblest, and which is consequently the greatest in being, since that which has the greatest truth is also greatest in being. . . . There is therefore something which is the cause of the being of all things that are, as well as of their goodness and their every perfection. This we call God” (ibid.).


(5) Fifth, and finally, Aquinas appeals to the fact that


“some things, like natural bodies, work for an end even though they have no knowledge. . . . Now things which have no knowledge tend towards an end only through the agency of something which knows and also understands, as an arrow through an archer. There is therefore an intelligent being by whom all natural things are directed to their end. This we call God” (ibid.).


All five “ways” of demonstrating God’s existence ultimately reduce to the cosmological argument, moving from an event or aspect of reality to what Aquinas insists must be its first and original Cause, namely, God.


·First, why is the idea of an infinite regression of causes impossible? Why must there be a first cause antecedent to which there are no other causes?


·Second, even if Aquinas is correct in positing a first and altogether independent Cause, on what grounds does he identify this First Cause with the God of the Bible?