As part of his method of radical doubt, Descartes speculates that perhaps

As part of his method of radical doubt, Descartes speculates that perhaps there is an “evil genius”—an all-powerful being, bent on deceiving us at every turn without our awareness.  While this may sound fantastical, some philosophers consider this a compelling argument against the possibility of achieving absolute certainty regarding any of our beliefs, and they credit this argument with highlighting the epistemological predicament we face:  since all of our beliefs about reality are filtered through our consciousness, how could we ever be sure that our conscious experience accurately corresponds to the way the world really is, independent of our consciousness?  Descartes, of course, believed that his Cogito Ergo Sum argument  (“I think.  Therefore, I am.”) could withstand the challenge of an evil genius—as an inference that was beyond any doubt.

What do you make of Descartes’ evil genius argument?  Can any of our beliefs—including those you may have endorsed in the previous discussion board--stand up to this challenge, such that we could endorse them without any doubt?   What about Descartes’ Cogito Ergo Sum argument?