¶ … existence or non-existence of God forms a very central basis to the philosophies of some thinkers. This paper examines the philosophies of Descartes, Kant and Sartre in order to determine the significance and connection of belief in existence and non-existence of God with their respective philosophies. DESCARTES, KANT AND SARTRE

The existence of God, the necessity of assuming that God exists, or the non-existence of God play a crucial role in the philosophies of either of the thinkers, namely, Descartes, Kant and Sartre. The existence of God is central to the philosophies presented by Descartes in the sense that he can explain away the questions that do not have simple answers with the existence of God. As a result, he does not have to provide absolute logic for questions whose answers might be out of human grasp anyway; instead he focuses on the intangible proof to state that God does exist. By asserting this as an unchangeable truth, Descartes proceeds to convey his entire philosophy. Kant, however takes a slightly different route but the notion that assumption of God's existence is necessary, plays an important role in his philosophy as well. Since Kant was a devout moralist, going so far as to preach accommodating morality within political conduct, existence of God is a central necessity to his philosophies. Since Kant believed that morality ultimately leads to religion, his entire philosophy of morality would fall apart if God was left out of the equation. Hence it can be stated that existence of God was necessary to philosophies presented by Kant. In direct contrast to these two philosophers, Sartre claimed that there was no such being as God or that God did not exist. Again such a claim was central to Sartre's philosophies since he proceeded to develop them on this one notion. Sartre, known as an atheist existentialist, believed that God was dead; as a result he proceeded to form his philosophies using this basis. Sartre formed his philosophies regarding the human condition in a world that did not have an overseer who could have otherwise provided basis and structure for the world patterns. Therefore non-existence of God was crucial to the philosophies of Sartre because he attempted to form them keeping God out of the equation (Levine, 1998).

The fact that existence or non-existence of God plays a central role in the philosophies of Descartes, Kant and Sartre is supported by the length of their respective arguments. In other words, each of these three thinkers has argued extensively in favor of their respective arguments. Beginning with Descartes, he believes that an individual can reach the same conclusion as his through various means. Firstly he argues that God can be felt as a value that is independent of the will of the object. Secondly he argues that the cause and effect profile or the objective reality also supports existence of God. His first argument is rather intangible and he asserts that it is supposed to be so. However he fully explains his second argument about cause and effect. Descartes claims that an object has an effect when it arises from a cause. In other words, the mind creates thoughts and ideas regarding a form on a physical plane and widens this form so that it is extended to become a reality. Moreover he asserts that the fact that he believes in the existence of God is in itself a proof of His existence. What Descartes is attempting to say here is that since this belief has occurred to him, it must have been planted in his mind by some outside factor; and this outside factor is superior to the worldly objects since it has the ability to plant beliefs. Finally Descartes argues that there is a God because he, as a human being, exists and this being, himself is not God. Since a human being is not independent of other existences, and form and matter, he cannot attain the status of a supreme being. Hence God has to be necessary and external entity. Kant, on the other hand, holds different views regarding providing evidence for the existence of God. Kant states that if anything exists at all, an absolutely necessary being must also exist. Since I or any other object exists, it follows that an absolutely necessary being also exists. Introducing subjects and predicates, where one exists when another exists, Kant states that the necessary being can be determined in one way only: by any one out of every possible pair or combination of opposed predicates. Therefore the proof for existence of God must be located through...

As a result, the concept of ens realissimum is the only concept through which a necessary being can be derived. In other words, a supreme being necessarily exists and cannot be proven through the traditional arguments (Levine, 1987). As for Sartre, he has evolved his argument that God does not exist through his theory of nature of human existence. He begins by saying that the fundamental distinguishing characteristic of human "Being" (ontology) is his ability to make free choices. This freedom makes man a "subject," rather than an "object." Sartre further equates this freedom with complete autonomy, arguing that a being is a law in itself. Thus he states, "If man exists, God cannot exist...," because God's characteristics are such that a human being is reduced to the status of being an object which in turn destroys his distinguishing characteristic of freedom. Sartre continued by saying that God's attribute of omniscience would not allow free moral choice to humans because a free choice should not be subject to scrutiny whereas with God's existence human beings are always under scrutiny of a Supreme Being (Stevenson, 1987). Furthermore, Sartre also denied God's existence based on the argument that God, by His very nature is a "self-caused being." In other words, God would have to be ontologically already present in order to create Himself. Since such a phenomenon is highly illogical, Sartre concludes that God does not exist.
God's possible existence is strongly connected to Kant's theory of existentialism in the sense that God is at the end of morality. Since achieving morality should be a human being's target, for Kant a believer could have faith in God because this faith would complement and echo the reason and the categorical imperative. Kant believed that since the human beings have the autonomy to create moral values, it is rational to have faith in a God who gives meaning and purpose to the moral realm of existence. In other words, since there has to be something more to achieving morality than just the immediate benefits, a higher purpose or meaning is achieved when a human being believes in God. Moreover Kant claims that God is necessary to existence. Since his claim is profound, it has to affect the rest of his theory. Keeping God as an imperative, Kant proceeds to give his views regarding morality. In other words, Kant includes God in the equation. Furthermore when Kant defines religion within the limits of reason alone, he is making the assumption that God's will is the ultimate goal, even superior to achieving morality. If Kant would not have believed in God, his theories regarding morality would be drastically different. When he considers religion within the limits of reason, Kant states that the basis of God's existence arises out of morality but that God does not become the basis of moral obligation. Therefore Kant himself makes a powerful connection between morality and existence of God when he states that morality eventually leads to religion. Furthermore Kant states that morality extends itself to accommodate the notion of a powerful moral lawmaker who exists as a separate entity from mankind. Conducting oneself in accordance with the will of this separate entity is what Kant considers achieving the highest moral state of being which ought to be man's final destination.

The claim that God does not exist provides a deep connection to Sartre's theory of existentialism. When Sartre claims that God does not exist, he is trying to create an understanding of the world that operates without the "prime-mover." The importance of the connection between his claim that God does not exist and his theory of existentialism can also be understood within the context that his theories would be very different, had he believed that God does exist. Since he proceeded to develop his theories of existentialism on this one notion, Sartre gave a world view that was completely autonomous, free in itself. Sartre, as an atheist existentialist, bought the notion that God was dead; as a result he proceeded to form his philosophies using this basis. Therefore it can be stated that the connection between his theories regarding human conditions in this world and God's non-existence is profound since one cannot exist without the other.

Descartes believed in the validity of ontological and cosmological arguments that supported God's existence whereas Kant took the opposite stance by stating the impossibility of generating proof from these…