Philx1001 Introduction to Philosophy - the Evil Demon Argument, Its Objection, and Response

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A possible response a skeptic could raise to argue against this objection is: the idea of the false sky is also injected to our minds by the evil demon. The demon, as he is all-powerful and tries his best to deceive us, knows that we might have a doubt about the existence of the sky, so he constructed a double-folded illusion. That is to say, the doubt itself, which we think is the internal product of our minds, is predicted and enforced by the evil demon. If we make an analogy of our mind to a computer, which runs a program, then the program is written by the evil demon. The program, which is a grand scheme that includes the part where we doubt that whether or not there is a sky, is designed by the evil demon, for that the malevolent demon bents on deceiving us as much as possible.

This response could be further attacked by additional objections, however given that the skeptics are radical and are prone to have an unmitigated doubt on our external world, I think this response is plausible. Descartes concludes in the end that he is “finally compelled to admit that there is not one of my former beliefs about which a doubt may not properly be raised”. Thus in my opinion, the skeptics’ response possesses certain validity because it endorses the underpinning idea: it is not in our senses’ power to arrive at the knowledge of any truth of the external world.

In conclusion, Descartes holds an a posteriori opinion that humans could not trust their senses or constructing true knowledge from their senses. We could only obtain knowledge of this world through reasoning and deduction, which is a priori. Evil Demon argument serves as the cornerstone of the Meditation as it proves that we cannot be certain of anything, upon which Descartes further develops more reasons as to why he must to mistrust his senses.