Here’s a summary of Lewis’ argument for existence of God from the existence of objective morality taken from his book “Mere Christianity.” I’ve sought to summarize his argument and provide some helpful quotes from it.
Ch 1: Objective Moral Laws Really Exist and We Fail to Keep Them.
-“appealing to some kind of standard of behavior which he expects the other man to know about.” (15)
-“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.” (19)
Ch 2: Dealing with Objections.
-Aren’t morals just herd instinct? We don’t deny that instincts play some influencing role, but moral obligation is different: “feeling a desire to help is quite different from feeling that you ought to help whether you want to or not.” (20)
-Aren’t morals just mere social conventions? We don’t deny that society has some role in shaping morals, but we assert that moral truths exist that transcend societies. Just as mathematical truths or historical truths exist (22-23).
-“the moment you say that one set of moral ideas can be better than another, you are, in fact, measuring them both by a standard, saying that one of them conforms to that standard more nearly than the other. But the standard that measures two things is something different from either. You are, in fact, comparing them both with some Real Morality, admitting that there is such a thing as a real Right, independent of what people think, and that some people’s ideas get nearer to that real Right than others.” (23)
Ch 3: The Reality of the Law
-The moral law we sense is different from other laws, like gravity. Gravity describes what happens, but the moral law tells us what OUGHT to happen (26).
-The moral law cannot be equated with ‘what works’ or pragmatism. We find that what we OUGHT to do often is not necessarily helpful or useful to us, but we sense that we ought to do it anyways (27).
-“there is something above and beyond the ordinary facts of men’s behavior, and yet quite definitely real—a real law, which none of us made, but which we find pressing on us.” (29)
Ch 4: What Lies Behind the Law (What are the implications for that facts of Moral Realism?)
-“men find themselves under a moral law, which they did not make, and cannot quite forget even when they try, and which they know they ought to obey” (31)
-If I look at two ways of thinking about the universe, naturalism or theism, naturalism could never account for the presence of real moral values “you can hardly imagine a bit of matter giving instructions” (33).
-Thus the presence of moral values is a CLUE that points to a mind that gives us this law (33) =God!
Ch 5: We Have Cause to Be Uneasy
-Because of the reality of objective morals and our inability to keep them, we are in trouble.
-“For the trouble is that one part of you is on His side and really agrees with his disapproval of human greed and trickery and exploitation. You may want Him to make an exception in your own case, to let you off this one time; but you know at bottom that unless the power behind the world really and unalterably detests that sort of behavior, then He cannot be good. On the other hand, we know that if there does exist an absolute goodness it must hate most of what we do. This is the terrible fix we are in. If the universe is not governed by an absolute goodness, then all our efforts are in the long run hopeless. But if it is, then we are making ourselves enemies to that goodness every day, and are not in the least likely to do any better tomorrow, and so our case is hopeless again. We cannot do it without it, and we cannot do with it. God is the only comfort, He is also the supreme terror: the thing we must need and the thing we most want to hide from. He is our only possible ally, and we have made ourselves His enemies. Some people talk as if meeting the gaze of absolute goodness would be fun. They need to think again. They are still only playing with religion. Goodness is either the great safety or the great danger—according to the way you react to it. And we have reacted the wrong way.” (36-37).
-“Christianity simply does not make sense until you have face the sort of facts I have been describing. Christianity tells people to repent and promises them forgiveness. It therefore has nothing (as far as I know) to say to people who do not know they have done anything to repent of and who do not feel that they need any forgiveness. It is after you have realized that there is a real Moral Law, and a Power behind the law, and that you have broken that law and put yourself wrong with that Power—it is after all this, and not a moment sooner, that Christianity beings to talk.” (37)
-“I wish it was possible to say something more agreeable. But I must say what I think true. Of course, I quite agree that the Christian religion is, in the long run, a thing of unspeakable comfort. But it does not begin in comfort; it beings in the dismay I have been describing, and it is no use at all trying to go on to that comfort without first going through that dismay” (38).