Once Descartes has "proved" his existence by way of the Cogito argument, and has determined what it is that belongs to his essence of being a thinking thing, he must move to examining questions about the world around him. However, before doing this, he thinks it better to examine the question of the existence of God. If he can prove that he was created by a perfectly benevolent creator, then his innate ideas must carry some semblance of truth, as God is not a deceiver and has placed these ideas in Descartes. Knowledge of God will allow the possibility of achieving understanding of the fundamental principles of the universe.1
Descartes offers two arguments for the existence of God. The first, considered in Meditation Three, is known as the "Trademark Argument." The second, proposed in Meditation Five, is called the "Ontological Argument." This essay will consider the former alone.
The Trademark Argument arises out of the fact claimed by Descartes that there is within each of us an idea of a supreme being, which was placed within us by the thing that created us. The purpose of this idea was to act as the mark of a tradesman placed within us. From examination of this idea, it follows, says Descartes, that God exists. His argument firstly involves the acknowledgement of such an idea within ourselves. This idea of God is one of a being who is "eternal, infinite, omniscient, omnipotent, and the Creator of all things that exist apart from him." This is the first premise of the argument (of course, this has not yet shown that anything corresponding to the idea exists). Secondly, there is the "Causal Adequacy Principle." This principle implies that any object must have as its cause something that contains at least all the attributes of the object if not more. Descartes off ...