He states “cogito, ergo sum”, that is, I think, therefore I am. By saying this, Descartes demonstrates that in order to think one must exist and therefore not be the puppet of an Evil Demon. As stated by Keith Crome in his essay on the Evil Demon, “as Descartes observes, for all that there is an omnipotent and cunning deceiver dedicated to constantly deceiving, he cannot cause me to be nothing, for it is beyond doubt that if I am deceived, I exist." This simply points to the fact that to be controlled and realize the fact you have to actually be real. And at that point, if there were to be an evil demon controlling all our actions, why would he admit the doubt that we are in charge, from which the theory itself arises? If we were truly in control, wouldn't we go through life without ever questioning whether or not we were real? Compared to my initial answer, the evil demon doesn't change much, because either it is or it isn't, and there's no certain way to know. All we have for certain is "I think, therefore I am" to demonstrate that we are thinking beings and this is enough to contradict Evil