Ontological arguments are a priori, which show that God exists without appealing to a sense experience. These ontological arguments argue about what God is to where he is from. St. Anselm, the creator of the ontological argument, based his theory on that we cannot think of anything greater than God. Therefor God must exist, why you might ask? If the greatest thing that we can conceive does not exist than we can still conceive the greatest thing that does exist, and that would be God.
The best explanation to the existence of God through St. Aquinas’s argument is that God does not exist as the first efficient cause. The argument for God, as presented by St. Aquinas, attempts to show that the existence of the world and everything within it can only be explained if there is a God who is the first efficient cause. The argument states that it is impossible for any being to be the efficient cause of itself because then it would have to bring itself into being, and to bring itself into being, it would have to exist before it existed. If a being exists, it is because some being before it caused it to exist. Therefore, if no first cause exists, neither will any other being exist.
St. Anselm (1033-1109) was a Benedictine monk; his philosophical views were very much influenced by Plato (Mavrodes 26). His greatest works were Monologium, Proslogium, Cur Dues Homo. St. Anselm had many views on God and religion, but instead of asking if God existed, he asks if the nonexistence of God was conceivable (Mavrodes 26). To proof this statement he followed it up with several statements such as: "Truly there is a God, although the fool hath said in his heart, there is no God." In addition, "God cannot be conceived not to exist.
Spinoza’s method of proving one substance relies upon his definitions and reason. I take further issue with this method because God cannot be proven through reason alone. Through this same reasoning Spinoza gives life too much meaning. In his argument, he claims that since God is the only substance all things flow from God. Meaning that everything in existence is a part of
It should be noted that this entire argument was formed from reason which is the process of forming conclusions and judgements through logic. As a result, a prior (first hand) knowledge is used. The first part is focused on proving God’s existence. Anselm began with his definition of God. That God is “that then which nothing greater can be conceived” (Id quo nihil mauis potest), meaning that it is impossible for there to be a more perfect being.
To make such an affirmation about a being absolutely infinite and supremely perfect, is absurd; therefore, neither in the nature of God, nor externally to his nature, can a cause or reason be assigned which would annul his existence. Therefore, God necessarily exists. --The potentiality of non-existence is a negation of power, and contrariwise the potentiality of existence is a power, as is obvious. --In this last proof, I have purposely shown God's existence a posteriori, so that the proof might be more easily followed, not because, from the same premises, God's existence does not follow a priori. Imperfection, on the other hand, does annul it; therefore we cannot be more certain of the existence of anything, than of the existence of a being absolutely infinite or perfect --that is, of God.
Anselm’s argument he starts by stating the concept of a “being than which no greater can be conceived”. This statement is one of the strategies Anselm uses to defend the existence of God. St. Anselm has confidence that if individuals understand the terminology of God and existence and also can understand what it means to speak of him, they must then come to the conclusion that he is of existence (Halsall, par. 14). This statement then leads everyone to believe that God definitely exists in our understanding as well as the atheist mind.
The ontological argument argues that if you understand what it means to talk about God, you will see His existence is necessarily true. Anselm defined God as 'that than which nothing greater can be conceived', hence God must exist. Anselm also believed that even atheist had a definition for God even just to disregard his existence; hence God exists in the mind. Anselm said this is so because that which exists in reality is greater than that which exists purely in the mind. In the words of Anselm, "Therefore, Lord, not only are You that than which nothing greater can be conceived but you are also something greater than can be conceived.
McCloskey’s article labels these arguments as “proofs” and concludes none of these arguments would be evidence of God’s existence. I find McCloskey’s article to lack logic and coherence which only serves to invalidate his arguments. I find this little more than an attempt to justify his own atheistic worldview. Coherence is an essential part of the theist’s belief structure. The individual arguments when joined collectively hold just that, coherence.
Thus, Anselm tends to base his argument on the definitions and terminology used. Anselm’s first form of the argument is that God is "that than which none greater can be conceived". Firstly, it must be emphasised that Anselm’s definition does not limit God to being the "greatest" but makes it known that nothing greater can be thought than God himself. Therefore, God should not in any way be linked to terms such as ‘omnipotent’ as terminology such as this limit him to what he really is. With this definition, he attempts to prove that not only does God exist in the mind but also in reality.