In Discourse on Method and Meditations on First Philosophy, Descartes attempts to rebuild his idea of reality, to see if he really knows anything, or if his ideas can be destroyed by the slightest hint of a doubt. In his pursuit of reality, Descartes encounters the problem of a powerful and malicious entity, an evil demon. Descartes believes this evil demon could be deceiving his entire existence, including any or all of his beliefs, sensations, and perceptions. Due to this belief, he concludes that he will “never be capable of being completely certain about anything else” (71) if he is not certain a God exists. If such a God does exist, can he prove beyond a doubt whether or not this God is a deceiver? Henceforth, I will attempt to illustrate how Descartes proves God’s existence and therefore solves the entire issue of a deceiving Evil Demon’s existence.
In his evil demon argument, Descartes suggests that whatever one person may be doing could be controlled entirely by an all powerful and deceiving Entity, whom Descartes claims to be the “evil demon.” For example, one could be eating chocolate cake and believe they are eating chocolate cake because they willed to, but in reality it could be the cause of an all powerful evil demon deceiving them into eating chocolate cake. Simultaneously, this demon causes one to believe they desire chocolate cake due to their own will. This leads to Descartes’ proclamation that one may know the contents of one’s will, but cannot be sure it is truly his or her own will.
Descartes claims that he has also experienced in his daily life, times when certain ideas appearing to him have not “[depended] on [his] will…for [he] often notices them even against his will” (72). Descartes makes the argument that something exists outside of himself that causes him to feel that idea. For example, a person walking outside on a windy and snowy day feels cold even though they do not will to feel cold. The idea of cold is coming from something existing outside of their being; in this case the wind and snow are causing them to feel cold. But, he claims that the reality of an idea has certain degrees; the highest of which belongs to infinite substances. Since his idea of a supreme deity is a being “eternal, infinite, omniscient, omnipotent…”, then this supreme deity will “clearly have more objective reality within it than do those ideas through which finite substances are displayed” (73).
Since, an infinite regression of causes cannot be allowed in the idea of God and the certainty of God’s existence is necessary to understand the argument of the Evil Demon’s existence, Descartes states that the cause of an idea must have as much reality as the idea being presented. From understanding that all human beings are capable of making mistakes and “what is more perfect cannot come into being from what is less perfect,” (73) it is understood that the idea of God could not have originated from a human being. Since God is perfect (as in possessing highest morals and being an infinite substance) and human beings are more or less imperfect and finite substances, the idea of God then must have “proceeded from some substance which really was infinite.” Thus, it is proven that the cause of an idea must have as much reality as the idea presented. Since the former is proven true, it is also true God exists.
Since it has been proven that God exists and that God is perfect, having highest morals, it is also proven that an Evil Demon could not possibly be continually deceiving a person. The idea of God is a being that has all the perfections one cannot even come to imagine, a being that has no defects. For a person to be deceptive a defect must be present, therefore “it is quite obvious that [God] cannot be a deceiver” (80). Since the Evil Demon would be deceptive, the Evil Demon possesses an imperfection, and imperfection it has been proven is not a characteristic of God. It has also been proven that something perfect cannot come into being from what is less perfect. Due to this revelation, God could not have been created by the evil demon; God exists at a higher level than the evil demon and is the all powerful, perfect, benevolent being and so, would not allow us to be deceived by the evil demon.