"These, then, are the two points I wanted to make. First, that human beings, all over the earth, have this curious idea that they ought to behave in a certain way, and cannot really get rid of it. Secondly, that they do not in fact behave in that way. They know the Law of Nature; they break it. These two facts are the foundation of all clear thinking about ourselves and the universe we live in."
From Book I, Chapter 1, The Law of Human Nature
"My argument against God was that the universe seemed so cruel and unjust. But how had I got this idea of just and unjust? A man does not call a line crooked unless he has some idea of a straight line. What was I comparing this universe with when I called it unjust? If the whole show was bad and senseless from A to Z, so to speak, why did I, who was supposed to be part of the show, find myself in such violent reaction against it? A man feels wet when he falls into water, because man is not a water animal: a fish would not feel wet. Of course I could have given up my idea of justice by saying it was nothing but a private idea of my own. But if I did that, then my argument against God collapsed too - for the argument depended on saying that the world was really unjust, not simply that it did not happen to please my private fancies. Thus in the very act of trying to prove that God did not exist - in other words, that the whole of reality was senseless - I found I was forced to assume that one part of reality - namely my idea of justice - was full of sense. Consequently atheism turns out to be too simple. If the whole universe has no meaning, we should never have found out that it has no meaning: just as, if there were no light in the universe and therefore no creature with eyes, we should never know it was dark. Dark would be without meaning."
From Book II, Chapter 1, The Rival Conceptions of God
That's all for now, I will continue to update this post as I continue reading the book.
Update 2/28/2013
"What is the problem? A universe that contains much that is obviously bad and apparently meaningless, but containing creatures like ourselves who know that it is bad and meaningless. There are only two views that face all the facts. One is the Christian view that this is a good world gone wrong, but still retains the memory of what it ought to have been. The other is the view called Dualism. Dualism means the belief that there are two equal and independent powers at the back of everything, one of them good and the other bad, and that this universe is the battlefield in which they fight out an endless war. I personally think that next to Christianity Dualism is the manliest and most sensible creed on the market. But it has a catch in it.
The two powers, or spirits, or gods-the good one and the bad one-are supposed to be quite independent. They both existed from all eternity. Neither of them made the other, neither of them has any more right than the other to call itself God. Each presumably thinks it is good and thinks the other bad. One of them likes hatred and cruelty, the other likes love and mercy, and each backs its own view. Now what do we mean when we call one of them the Good Power and the other the Bad Power? Either we are merely saying that we happen to prefer the one to the other-like preferring beer to cider-or else we are saying that, whatever the two powers think about it, and whichever we humans, at the moment, happen to like, one of them is actually wrong, actually mistaken, in regarding itself as good. Now if we mean merely that we happen to prefer the first, then we must give up talking about good and evil at all. For good means what you ought to prefer quite regardless of what you happen to like at any given moment. If "being good" meant simply joining the side you happened to fancy, for no real reason, then good would not deserve to be called good. So we must mean that one of the two powers is actually wrong and the other actually right.
But the moment you say that, you are putting into the universe a third thing in addition to the two Powers: some law or standard or rule of good which one of the powers conforms to and the other fails to conform to. But since the two powers are judged by this standard, then this standard, or the Being who made this standard, is farther back and higher up than either of them, and he will be the real God. In fact what we meant by calling them good and bad turns out to be that one of them is in a right relation to the real ultimate God and the other in a wrong relation to him.
The same point can be made in a different way. If Dualism is true, then the bad Power must be a being who likes badness for its own sake. But in reality we have no experience of anyone liking badness just because it is bad. The nearest we can get to it is in cruelty. But in real life people are cruel for one of two reasons-either because they are sadists, that is, because they have a sexual perversion which makes cruelty a cause of sensual pleasure to them, or else for the sake of somthing they are going to get out of it-monrey, or power, or safety.
From Book II, Chapter 2, The Invasion