Unless there is a God....

The following is taken from the chapter, The Skeptical Student, in Tim Keller's book Encounters With Jesus.

W.H. Auden moved to Manhattan in 1939. By that time he was already a great writer, and he had abandoned his childhood faith in the Church of England, as had most of his friends in the British intellectual classes. But after World War II broke out, he changed his mind, and he embraced the truth of Christianity... What happened?

(Auden in his own words:)

If I am convinced that the highly educated Nazis are wrong, and that we highly educated English are right, what is it that validates our values and invalidates theirs? The English intellectuals who now cry to Heaven against the evil incarnated in Hitler have no Heaven to cry to. The whole trend of liberal thought has been to undermine faith in the absolute. It has tried to make reason the judge. 

Auden had moved away from Christianity as obsolete and unhelpful. But the rise of the Nazis made him see something. He believed in human rights, in liberty and freedom. But why did he? The operational principle of the natural world is that the strong can eat the weak. So if it's natural for the strong to eat the weak, and if we just got here only though the natural, unguided process of evolution, why do we suddenly turn around when the strong nations start to eat the weak nations and say, That is wrong? On what basis can we do that? On what basis can we say that genocide in the Sudan [or Syria, or of the Yezidis in Iraq, to bring it up to date] where a strong ethnic group "eats" the weak one, is wrong? If there is no God, then my views of justice are just my opinion- so how then can we denounce the Nazis?

Auden realised that unless there was a God, he had no right to tell anybody else that his feelings or ideas were more valid than their feelings or ideas. He saw that unless there was a God, all the values we cherish are imaginary. And because he was sure they were not imaginary- that genocide was indeed absolutely wrong- he concluded that there must be a God.