"Badness is only spoiled goodness. The bad power cannot supply himself either with good things to desire or with good impulses to pervert. He must be getting both from the Good Power. Evil is a parasiste, not an original thing. The powers which enable evil to carry on are powers given it by goodness. Christianity thinks this Dark Power was created by God, and was good when he was created, and went wrong. The universe is at war, but this is not a war between independent powers (dualism). We are living in a part of the universe occupied by the rebel. Christians believe that an evil power has made himself for the present the Prince of this World.
   How did the Dark Power go wrong? The moment you have a self at all, there is a possibility of putting yourself first ­ wanting to be the centre ­ wanting to be God, in fact. That was the sin of Satan: and that was the sin he taught the human race. What Satan put into the heads of our remote ancestors was the idea that they could "be like gods" ­ could set up on their own as if they had created themselves ­ be their own masters ­ invent some sort of happiness for themselves outside God, apart from God. And out of that hopeless attempt has come nearly all that we call human history ­ money, poverty, ambition, war, prostitution, classes, empires, slavery ­ the long terrible story of man trying to find something other than God which will make him happy." (C. S. Lewis - Mere Christianity. Macmillan Publishing, 1978. Pgs. 49-54)