Upon breaking down the elements of how senses gather information Rene Descartes begins to realize that all these elements also exist in dreams and it is very difficult for him to create a clear distinction between dreams and reality because they share the same elements and often you have a dream that seems real but then is justified as a dream by the act of waking. The only argument Descartes poses against the idea of the devil tricking us is that for a loving god to exist this has to be false because a loving god who created us in his image would not want us to be deceived because by definition this god is good and if something is all knowing and powerful and good this being would never allow something evil to make us believe something that is in fact false.
For example god sets out that killing is wrong in the Ten Commandments written in stone but then tells Abraham to kill just to see if he would. Basically god’s word in that situation directly from his mouth overrides his previous decision set in stone; Murder was evil but then became good for a short period. For that brief period god promoted evil. Can god change his/her mind and if so what impact does that have on the validity of his/her morality? Is man merely a mistake of God's? Or God merely a mistake of man's? (Friedrich Nietzsche 1900, Twilight of the Idols, Maxims and Arrows) Can we be sure what he actually said is even interpreted correctly? What if god is misunderstood? Is it possible that god could be evil and controls our actions under the pretence of being good or say evil is subjective and someone from another planet might consider everything we believe to be good as evil. However in the other perspective morality becomes something independent of god and god just tells us about it, so we don’t really need god to be objectively moral at all, because he’s served his purpose, we don’t need god to be moral because we already have his basic schema we just need to follow it.
“What is good? All that heightens the feeling of power in man, the will to power, power itself. What is bad? All that is born of weakness. What is happiness? The feeling that power is growing, that resistance is overcome.”
Friedrich Nietzsche, The Antichrist, section 2
In these terms god has little to no power over our actions, so to be evil is the same as good, a moral choice born of the existence of free will. Good is of our strengths and evil is a choice to give in to our weaknesses. As long as we have a choice we will have evil, god essentially allowed evil by giving us free will. (Friedrich Nietzsche 1900)
Descartes, Rene (1641) Meditations on First Philosophy. Print
Plato (424/423 BC) Euthyphro