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Thomas Aquinas and the Proof of Gods Existence Research Paper



Several theories have been explained by philosophers in attempt to prove that God exists. However, it is important to defend faith by first beginning to understand the fact of the existence of the world as a way of proving existence of God. Such lines of arguments are referred to as “cosmological” arguments (Thompson 284). My objective in this paper is to state and explain St Aquinas’s five ways on proving the existence of God.

Thomas Aquinas was a Christian theologian of the thirteenth century who applied Aristotle concepts to Christian theology. He endeavoured to devise a rational proof of existence of God by incorporating in part, upon conjectures of Aristotle that there must be a first cause (Owen 14). The first cause was the prime cause for creation. Initially, he devised five ways to prove existence of God; however, the first cause was termed by Thomas Aquinas as one which proceeds from the movement of sensible things.

The argument St. Thomas gives from motion had long and varying history. In regard to that history, it would seem at initial glance to be anything but an easy and manifest prove that God exists as Thomas understood as a Christian. The paper begins by reviewing literature related to Thomas Aquinas and the Proof that God Exists by examining (Owen 16).

A Review of Related Literature

Cosmological Argument for God’s Existence

Cosmological arguments are arguments presented to justify the existence of God. St Thomas Aquinas finds it useful to defend faith by presenting a way of proving that God’s existence emanates from the fact of existence of the world. The term cosmological refers to as ‘based on the fact of the cosmos’ (McKeon 14). The term has to do with cosmology a branch of metaphysics concerned with the universe as an orderly system. Obviously, the world exists and yet cannot explain its own existence. As such, something else must account for it. But, if we still don’t develop another unexplained existence of some kind, this “something else” must have within itself the cause of its own existence. Such example of an uncaused being is God (Thompson 284). This simple explanation provides the essence of cosmological argument; however it is enhanced and made logically defensive when stated more candidly. St Thomas Aquinas developed five ways of explaining the existence of God. The first three arguments are cosmological in nature (Wadia 54)).

The First Argument from Change

The first way of proving God’s existence is the argument from change. St Thomas thinks that our senses indicate without doubt that some of the things in the universe are changing. In essence whatever change must be caused to change by something other than itself (Thompson 330).

As a Christian theologian, Thomas embraced the concepts advanced by Aristotle to explain God’s existence. The argument when looked at in this way has its sources in physics and metaphysics (Thompson, 410). In physics, proof from motion seems to reach nothing further than a celestial soul.

In metaphysics, Aristotle’s demonstration arrives at a plurality of separate substances, each of which, although act without any mixture of potency, is nevertheless a finite entity. His argument in either case, that is, both physics and metaphysics, does the result of the proof at all resemble the Christian God (Thompson 284).

The Prima Via structure in the Summa Theologiae is remarkably clear (Reinchenbach 30). Its beginning point is situated in things of the sensible world, things which are evidently perceived through sensation to be in movement. Thomas Aquinas gives examples of fire heating wood and hand moving the stick which pushes something else. Analysis of this movement of sensible things reveals emergence of two successive propositions (Thompson 318).

In the first proposition, whatever is being moved is being moved by another; and second that an indefinite series of movents that are being moved cannot account for this motion. The conclusion from the analysis of the movement seen in sensible things is therefore that there is a first movent which is not being moved by anything, and this is all understood to be God (Wadia 420).

Accordingly, St Thomas constructs the arguments as follows: first, the starting point where some things in the sensible world are being moved; second, propositions where whatever is being moved is being moved by some thing else.

In addition, an indefinite series of moved movents cannot account for motion; and three, the conclusion where there is a first movent which is not being moved by anything at all, and this is understood as the existence of God (Wadia 416). The first of the two propositions emerges from a metaphysical examination of the movement witnessed in sensible things.

It is not agreeable in any a priori way, either analytic or synthetic, but is reached as a conclusion from what is seen happening in the sensible world. Thomas Aquinas reasoned with an evident example before his mind. “A piece of wood which is cold is being heated by a fire. The movement in this case is alteration, change in quality. Insofar as the wood is being moved from cold to heat, it is in potency to being hot.

This is at once seen to be the necessary condition for being moved. The thing that is being moved has to be in potency in the same respect. So nothing can move itself. If it is being moved, it is being moved by something else. The basis of this argument is that the act is something over and above the potency, something more than the potency, and so has to come from something which already has or is that act (Reinchenbach 96).

The Second Argument from Causation

The second proposition follows from a continuation of this study of sensible movement in terms of act and potency. If that which is causing the motion is thereby being moved itself, it is also necessary being moved by another. If this third is also a movent that is being moved, it is likewise being moved by still another. But one cannot proceed this way indefinitely, for there will be no first movement. Therefore there must be a first movent which is not being moved by anything; and this is all understood to be God (Fredrick 64).

Quite evidently, this evidence derives its force from the doctrine of act and potency explained in the proof of the first preposition. Anything that is being moved does not have of itself the act towards which it is being moved. So in an indefinite series of moved movents, none would have the act of itself.

Therefore, such a series would never be able to account for the motion. Since there is sensible motion, then there must be something which of itself is act, in the sense that it is in no way being actualized by anything whatsoever in causing the motion. Such a movent, Thomas notes without least hesitation, to be understood by all to be God (Fredrick 62).

In sum, Aquinas argues that there must be something on which this entire causal order depends for its existence. To him, God is this first cause who makes things to be and sets them in motion in turn makes other things to occur. It is therefore important to note that for Thomas the strict idea of temporal beginning of creation, as distinct from its eternal dependence on God as its first cause, cannot be derived from the basis of human reason, but must rather, come from revelation (Wippel 323).

Aquinas Argument from Contingency

St. Thomas third argument of contingency has become synonymous specifically as cosmological argument. He viewed it as an observed fact that some things have a start and an ending. These items are thus capable of either to exist or not to exist. This implies they are not necessary but contingent.

For if these things were necessary, they could not have had both the beginning and the ending. This leads to the conclusion of the presence of the necessary being to cause contingent beings; if not nothing could exist (Fredrick 60). Reichenbach (1972, 19-20) provides a modern angle of this argument when he states:

A contingent being exists. This contingent being is caused either by itself or by another. If it were caused by itself, it would have to precede itself in existence, which is impossible.

Therefore, this contingent being is caused by another, that is, depends on something else for its existence. That which causes (provides the sufficient reason for) the existence of any contingent being must be either another contingent being, or anon-contingent (necessary) being.

If then this contingent cause must itself be caused by another, and so on to infinity. Therefore, that which causes (provides sufficient reason for) the existence of any contingent being must be either an infinite series of contingent beings or a necessary being. An infinite series of contingent beings is incapable of yielding a sufficient reason for the existence of any being. Therefore, a necessary being exists.

We note that both Thomas and Reinchenbach’s forms of arguments commence with the existence of a contingent being. Contingent beings are vividly described by St. Thomas whereas Reinchenbach does not as it is an assumed fact that such exists. They postulate that a being that is contingent is one that doe s not need to exist.

In other words, it does not have the cause of its existence within itself, but relies for its being upon one or more other things. Contingent in terms of explaining God’s existence can be proved on the basis of time and change. All that exists in nature survive in the context of time (Reinchenbach 20).

Consequently, everything existing time undergoes change. In case change does not happen, imperatively, time has not elapsed. In other words, everything in nature undergoes changes. Nevertheless, everything that changes does so because it is affected by other things. If it had its various forms all together within itself, all these forms would exist at once, and in essence no change could happen. Thus, since everything that is affected by other things is contingent, everything in the universe is contingent (Thompson 312).

As a result of everything contingent being caused by something else, every being or item had to have a cause when people them in the natural realm. When people locate this cause, it is contingent and thus has a cause. This process may continue to infinity and still have a series of caused beings.

Because none of these could cause itself, none could exist unless there were anon-contingent being. Such a non-contingent being has its own cause in itself, thus is different from the other beings in that it must exist. In sum, it is possible to prove the existence of a non-contingent being because contingent beings exist (Ariel 298).

Aquinas third way differentiates between necessary and contingent beings. Human beings for instance, are contingent beings which come into existence and which can cease to exist. However, St Thomas argues contingent beings can only come into existence if they are caused to do so by an original cause of being whose existence is there as a matter of necessity.

Aquinas claims as before that this idea of a necessary being is what people refer to when speaking of God. Cosmological argument also offers distinction between existence and essence. For instance, the essence of man consists of all properties that make him a man, that is, his characteristics (McKeon 434). The properties that make the individual man do not make him exist. Therefore, a man’s essence is separate from his existence, and he is a contingent being.

Essence and existence in the eyes of God are identical. In other words, the essence of God is existence (Owen 14). God is a necessary being since it is God’s very nature to exist. God offers His creatures existence. However, the existence that he provides to them, though real, is not self existence like His own, but contingent existence (Thompson 345).

Argument of God’s Existence from Degree of Perfection

St. Thomas fourth proof of God’s existence is extracted from hi argument found in finite objects. He postulates that some things appear to be better, truer, nobler compared to other things. Every individuals has the ability to rate specific objects to be superior or more superior to other objects.

However, the degree of perfection can only be determined if there exists a being that is more perfect. To insinuate that something is more perfect than something else is to concur that it more closely approximates the perfect. In affirmative, the perfect must exist (Caputo 686).

Aquinas fourth argument observes values in human beings such as beauty, goodness and truth. He inquires where such things come from. He argues that existence of such values means that something must exist that is the most good, beautiful and true and this brings such human values into existence. Infact, that something is God who is the perfect and original cause of these values (Caputo 680).

Aquinas’s Argument of God’s Existence from Design

In this way of explaining the existence of God, St. Thomas argues that there exist clear signs of design within what terns as natural order. According to him, things don’t just occur; they appear to have been designed with some form of purpose in mind. This aspect of nature has been examined often in relation to natural sciences.

The orderliness of nature evident, for instance, in the laws of nature, seems to be a sign that nature has been designed for some purpose. It essentially for this point that naturalists approaches to science especially those that argue that matter possesses an intrinsic capacity to organize itself, are viewed as such a threat by some modern Christian apologists (Southgate 52).

Aquinas’s design argument became popular following the scientific revolution. The universal law of gravitation and laws of motion by Sir Isaac Newton suggested a mechanistic universe, carefully designed with a purpose in mind.

However, the weaknesses of this argument were philosophically exposed by Hume David who intimated to the degree of disorder or natural evil in the world as a significant countervailing fact. It was also exposed by Charles Darwin when he provided an alternative explanation of apparent design of the natural world in his evolution theory by natural selection (McGrath 182).

Aquinas viewed creation as both depending on God for its existence at every moment, but as also having been granted its own integrity to unfold according to its God given nature through the action of secondary causes striving, under inspiration change drawn from God’s spirit, too attain their desired end and fulfillment in God.

The fifth way views the intelligent design in the world, that is, things seem to be adapted with certain purposes in mind. The source of this design or natural ordering must, St. Thomas reasons, in be some intelligent being, God, who works out God’s purposes in creation (Southgate 52).

With his arguments for existence of God, Thomas developed the concept that nature had purposes deriving from God’s design. These purposes did not only offer evidence of God, they also provided a natural revelation of the end of creation. Thus, the eternal law of God is revealed in divine law through the scriptures and in natural law, reflected in the nature of creation itself.

If every part of creation naturally tends to seek its natural end or good, in the case of human beings this takes particular form in the search to know God and to construct an ordered society reflecting the well being of God’s good order. In constructing such a society, in addition to biblical commands, natural law means that human beings can identify universal and eternal moral standards.

Human law is therefore laid on these moral standards, and indeed the natural law provides a framework for laws in specific situations. The advantage of this is that it offers the opportunity of agreement on international law across different countries and cultures. This is evidenced in the role it played in developing concepts such as just war theory.

Objections to Cosmological arguments

Cosmological arguments received a number of objections from various philosophers. Kant Immanuel and others are among those who have objected that Aquinas cosmological arguments are depended upon ontological (Runyan 56).

According to objectors of cosmological arguments views, they eliminate cosmological arguments as an independent proof. Kant noted that the argument proves the existence of a necessary being. He however, alleged that it relies upon the ontological argument to indicate the properties of that being are those of God (Ariel 298).

Reichenbach on the other hand objected to this argument. He intimated that Kant classified cosmological argument into two categories; one, which Kant contented to be sound to prove existence of a necessary being, and two, which Kant claimed to, disagree, indicates that this being is God (Reichenbach 142).

Works Cited

Ariel R. Theistic Proof and Immanuel Kant. Journal of the American Academy of Religion, 1974.

Caputo, John D. Kant’s Refutation of the Cosmological Argument. Journal of American Academy of Religion, 1974, 686-691.

Fredrick, Copleston B. A History of Philosophy. New York: Image Books, 1962.

McGrath A. Christian Theology. New York: Wiley & Sons, 2010.

McKeon R. Thomas Aquinas Doctrine of Knowledge and its Historical Setting. Journal of Medieval studies, 1928, 434:14.

Owen H. Concepts of Deity. New York: Herder and Herder, 1971.

Reichenbach, Bruce R. The Cosmological Argument. Illinois: Charles C. Thomas.

Runyan, Mary E. The Relationship between Ontological and Cosmological Arguments. Journal of Religion, 40-60.

Southgate C. God, Humanity and the Cosmos. New York: Continuum International Publishing Group, 2005.

Thompson, Samuel M. A Modern Philosophy of Religion. Chicago: Henry Regnery, 1955.

Wadia P. Cosmological Argument. Religious Studies, 1975, 416-476.

Wippel, John F. The Metaphysical thought of Thomas. New York: CUA Press, 2000.

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