St. Thomas Aquinas attempted to prove the existence of God and His divine qualities in the book he wrote, The Summa Theologica, which included his famous work known as “The Five Ways.”  In the Five Ways, Aquinas selects two objections to the existence of god to disprove, to set forth in proving the existence of God. The connection between the metaphysics, knowing God to be real, and the epistemology, proving God to be real, does exist according to Aquinas. Aquinas argues that God’s existence can, in principle, be proved from His effects. Then gives his five ways as examples of how reason comes to know God.”  One could argue Aqiunas’ scope is so narrow, with only two objections; he hasn’t really proven anything, only potentially disproven two of the multitudes of objections which exist to the existence of God. Aquinas arguments, which are well thought out, do not prove the Existence of God, they merely give his reasoning and rationale, in his opinion that a reality beyond our five senses may exist. Although I do believe Aquinas reasoning to be logical, there are weaknesses in his argument that some other philosophers have shown in their critique of his work.
Aquinas theology and philosophy was pivotal in Roman Catholicism.  This work relied heavily on Aristotle’s belief of four causes, formal, material efficient and purposive that is all needed to cause an effect.  “He outlines These five ways as part of how God can be known by reason”  “The Five Ways” Aquinas uses are; “First Mover,” “First Cause,” Necessary Being,” “Greatest Being”, and “Intelligent Designer.”  “Each individual proof itself is not proof there is God, its all five proofs together that prove that God exists.”  “The First Mover” is an argument about motion, “Whatever is in motion, must be put in motion.”  Aquinas argued that this cannot go on for infinity because; “If there is no (un-moved) mover then there can be second (moved) movers; but there are second movers; therefore there is a First Moveraˆ¦.”  so therefore there has to be a first unmoved mover which Aquinas believed to be God.  This first proof is meant to prove God as the cause of universal change. 
Aquinas’s second way, a “First Cause”, explained as efficient causation, attempts to explain cause and effect.  Similar to motion, efficient causation cannot be infinite, so there has to be a first cause and without a first cause then there cannot be a second cause. “Infinite regress” is impossible because it means no “First cause.”  Aquinas is arguing that, “aˆ¦if no First (Uncaused) Cause, no second causes; therefore there is a First Cause.”  Aquinas believed the “First (uncaused) Cause” was created by God.
The third way, “Necessary Being”, explains that things in nature are possible to exist or not exist.  For example, a tree will grow leaves in the spring (begin to exist) and the leaves die in the fall (cease to exist). Then one can infer that things in our universe have a beginning and an end. If there was never a beginning then there will never be an end, “Therefore, if at one time nothing was in existence, it would have been impossible for anything to have begun to exist; thus even now nothing would be in existence—this was absurd.”  Similar to causation, necessary things cannot go on infinitely and necessity is either caused by another or not.  Instead, we cause our necessity on others rather than receiving it from others. 
Aquinas’s fourth way is that of the “Greatest Being.” He is meaning that there has to be a source of “being, goodness, and every other perfection.”  “The concept of degrees being can be understood if we remember that “being” means not simply existence (“to be not to be”) but also essence (what a thing is, its nature)aˆ¦  to understand what is meant by degrees of a being is to refer to something as great, greater, or greatest.
The fifth way is that of an “Intelligent Designer”  “this is often called the ‘argument from design.’”  “As Paley said, if we find a watch, it is reasonable to conclude there is a watchmaker”  Aquinas noted in this way that all things that lack intelligence do not have the ability to move to an end without having something direct it to an end.  “Therefore, some intelligent being exists by whom all natural things are directed to their end.” 
Aquinas uses an interesting way to format his argument in this article. He sets up a question in this article; “Whether God Exists?” then gives two objections or possible answers.  He then gives a biblical reference where God says he exists, “I am Who I am” (Exod. Iii. 14).  Then he proceeds to give his five ways to support the objections and ends with his thesis to the antithesis.  Aquinas’ five ways seems to be more of a cosmological argument, which is essentially one way.  This type of argument contains six elements to it: motion, efficient causality, contingency and necessity, degrees of perfection, design, and the Kalam argument (time or big bang theory).  Aquinas used this type of argument to support his answer to the existence of God yet he omitted Kalam argument. Simply said, “Aquinas is exploring the human understanding of the origins and possible structure of existence.”  By using reason as a means of understanding our existence he explores “the different aspects of reality that he believes are apparent to an intelligent observer which aspects his ultimate explanations of God.” 
Understanding that the question Aquinas is setting to prove all in lies in the question that something at some time and place and with reason had to set everything we know through our five senses and logic, in motion. One of Aquinas weaknesses in his argument is reason alone cannot prove that there is a being and creator of our existence.  One can come to a rational belief based on the ways their reality has impacted their live. Meaning one’s experience has a large influence on their personal belief system. So how is it that one knows or believes something to be fact or truth and what is fact or truth based only on what we know?
Aquinas argued the two objections he posed. The first was the question of evil and that why a God of goodness would create evil.  He answered this by referring to what Augustine had to say about evil which essentially was God created evil to bring better good.  I do however; question how it is they knew this to be true. Sextus Empericus wrote an article, Can We Know Anything?, which challenges the theory of knowledge.  His purpose was to “acknowledge that everything we think we know is in fact uncertain.”  He claims, “in order to be convinced of the truth of an opinion or belief…we need a criterion of truth.”  Sextus writes that there is no way to reliably prove something to be true or false.  Therefore all the opinions of philosophers about such things as the elements, or the soul, or the gods, are all worthless and without foundation”  He skeptic viewpoint was intended to free the mind from needless worries and not to adhere or believe in the truth to any one doctrine.  So we can believe things to be true or false, good or evil yet we can’t prove that God was the creator of evil unless we believe he did.
In writing “The Five Ways” Aquinas was reasoning that we know in order to have an effect there must be a cause. He related this to the universe; he didn’t believe it caused itself and that some agent did, “and if the universe is eternal there must be a cause for this ‘perpetual motion’ and the cause” has to be God.  How is it that we can know this to be true other than believing it to be true. St. Augustine said, “The fact that we can discover a truth about God through our own faculties does not mean that we hold in our minds purely intellectual proof of the existence of God.”  Bertrand Russell argued that the chain of cause and effect is cyclical.  He quoted John Stuart Mill’s from his autobiography which, “My father taught me that the question, Who made me? cannot be answered, since it immediately suggests the further question, Who made God?”  Therefore he believed there is “no validity to the first cause.” 
The second objection to “The Five Ways” that Aquinas stated was that there was not a need for God to exist because all things can be reduced to nature and human reason or will.  He answered this by saying that nature “can be traced back to God as to its first cause.”  He also said that there “some higher cause other than human reason”  and that “things capable of motion and of defect must be traced back to an immovable and self necessary first principle.”  Bertrand Russell stated,
“aˆ¦to establish the existence of something is to demonstrate that actual instances of the idea under scrutiny actually exist in the world. No amount of scrutiny of the idea itself can establish with certainty the real existence of any instances of it.” 
What is it to know something to be real rather than believe it to be real? Hume believes we know things through our individual impressions.  He claims we cannot know “laws of nature, only our own habits; and we cannot deduce the truth from habits.”  So our impressions don’t necessarily give us a truth of how things really are.  “To say that God exists is to make a statement of fact; clearly therefore, it is not a statement whose truth can be established a priori.”  Essentially Hume claims it is possible to make an argument of God’s existence but because evidence is lacking, these types of arguments become invalid because we can’t prove them. 
I believe Aquinas used a posteriori  argument was based his faith and reason (which he believed put together discover truth)  in addition to the knowledge known to him at the period of time in which he lived. He was “arguing from experience to God’s existence.”  He argues that God’s existence can be proven by giving “his five ways as examples how reason comes to know God in it’s explanation of five kinds of effects,”  which are “based on different aspects the he believes are apparent to any intelligent observeraˆ¦”  Aquinas was trying to prove God’s existence can be proven without the use of faith and scripture.  Aquinas’ “aˆ¦argument alone does not prove that Allah (God) is the cause of the universe; it takes the first step in attempting to show that there must be a cause.”  If God is omniscience and omnipotent then I have to raise the question as to why there is a world of such imperfection? Hume wrote, “the philosopher can hardly avoid noticing how imperfect is our world and or; could God really be such an incompetent builder?”  It appears to me that Hume was questioning the state of goodness in our world, or lack of, and there is nothing we can do to prove God’s existence other than only formulate what our idea of an all perfect being could be if one existed.  Aquinas answered this question of evil/imperfection in his reply to his antithesis as to whether God exists, saying was created for the better good. 
So the question remains, is there a omnipotent being and did “God make nothing from nothing, ex nihilo fit?”  As I have shown that others philosophers argued that we don’t have factual information to prove or disprove that God exists, and is a being of perfection and the creator of the universe and all in it. St. Anselm questioned God’s omnipotence by stating, “that there are some things God cannot do; he is unable to undo the past, he is cannot make the true false or the false true and he cannot lie.”  So with this idea that an all powerful being is able to do anything he found some things that God cannot do, therefore maybe implying there is not a God. “The Gospel of St. John says: “Do not try to understand in order to believe; believe in order to understand. Faith precedes reason.”  From what Aquinas believes, “a conflict between reason and faith is impossible since they both originate in God.” 
So taking Aquinas argument in his article “Whether God Exists” I feel it is in need of some improvement. What is believed to be true today can be disproved tomorrow and so on. Scientifically there is not concrete proof of God and I have to lean on the side of skepticism there is not anyway to prove something/someone was the ultimate creator of the universe is a hard concept to believe unless one relies on their secular believes. As I have shown there are many philosophers whom also find weaknesses in Aquinas argument in the proof of whether God exists. Therefore, factually an existence of God cannot be proven. I believe it does come down to your own beliefs and if you truly believe God exists you will find every way to support your belief regardless of other opinions that refute it. On the opposing side if you don’t believe that God exists you will do the same. Aquinas’ argument appears to be one that will be answered at the time of our own death and only then, if we are blessed, will we know if there is a God because we will be in the presence of his glory or we won’t.