A few days ago I asked how Descartes went from “Cogito ergo sum” to proving the existence of God in his Meditations on First Philosophy (see here). I was skeptical of his argument and the more I thought about it the more I became skeptical of his first couple meditations as well.
Here is why:
(1) Descartes sought to find the one thing he could not doubt by doubting everything. The one thing he found was that he realized he was thinking and therefore he was a thinking thing. I think this can be doubted as well. It could be that there is a great being whose thoughts are so complex that when it imagines characters it also imagines the though life of characters. It would be like a 3-D version of John Grisham sitting down to write a novel. Another thing to consider would be a super computer that created a program where it simulated an artificial world that includes thinking beings as well as those being’s thoughts. Could we doubt these being exist in any “real” way? I think so.
(2) As Eric O. Springsted wrote (commenting on the arguments of Alasdair MacIntyre) we should note that Descartes never abandoned his language game, i.e. he never was able to think outside of French and/or Latin which provided him with a way of thinking and discussing concepts like thinking and doubting (see Philosophy for Understanding Theology, 2nd Ed. p. 235).
(3) Some confuse the probability that we exist, and the assurance that we exist, that we find in thinking and doubting with the absolute knowledge that we exist. In some Eastern religious schemes there is a teaching that we are part of a greater One and that “salvation” consist of escaping the misleading concept of our own autonomy. There are plenty of people throughout history that seem to have doubted that we are (in any serious way) existent. If we are part of a greater One or we are the imagination of a higher being we may be said to “exist” but not like Descartes was trying to prove.