Descartes' Fourth Meditation, he begins with the assumption that God exists, is infallible, and is not a deceiver. While those assumptions may be subject to debate, for the purposes of the analyzing his argument, they will be taken as the truth. From those truths, Descartes takes several steps to arrive at the conclusion that human error is not the result of a failure of either the will or of intellect, but due to the fact that the will's scope is so much greater than the scope of the intellect, that the two are essentially incompatible. However, while this conclusion may seem satisfactory, when one examines the various steps in Descartes' argument, it becomes clear that he does not always use sound reasoning to come to that conclusion. The first mini-conclusion that Descartes reaches in his argument is to conclude that, because man has been created in God's image, mankind's judgment, if used correctly, is infallible. Even within the bounds of the idea of an all-knowing, omnipotent, all-loving God, the idea that a man created in God's image must be infallible seems unlikely. After all, even if man has been created in God's image, a man clearly lacks some of the attributes of God. Mankind is mortal, which differs from God's image. Even the differences in intellect, appearance, and physical attributes between men suggest that while mankind, as a whole, may have been created in God's image, there is obviously room for variation in a number of different attributes. Descartes fails to address those differences. Certainly, God's perfection means that He is perfectly wise, perfectly beautiful, and...

The fact that humans naturally vary from him in those characteristics suggests that they might also naturally vary from him in infallibility.
Descartes next goes on to conclude that, despite being created in the image of an infallible God, human beings are fallible. However, Descartes notes that humans have a lack of absolute knowledge. That leads ones to question whether humans are actually fallible? Do human beings make mistakes in judgment and reasoning, or, given the information that they can obtain, are those mistakes actually examples of infallible logic and reasoning, but faulty knowledge. If human beings are coming to the correct conclusions given the knowledge that they have, does a mistake in judgment really indicate fallibility in logical reasoning? Therefore, the next assumption that Descartes makes, which is that humans must not be using their judgment correctly, seems unsupported by the evidence. After all, if one makes the best possible, most logical conclusion that one can make based upon the evidence one has in one's possession, that is not evidence that judgment has been used incorrectly, but could simply be evidence that one has received incorrect information.

Whether or not one buys into the Descartes' descriptions of human fallibility or that humans are not using their judgment correctly, one is forced to agree with his conclusion that humans do make errors. Some of these errors are mistakes that come from a simple lack of knowledge. The idea that the sun revolved around the earth was certainly a simple, logical conclusion for…