Terrence McNally interviews atheist Richard Dawkins on his new book 'The God Delusion.' From AlterNet

TM: Why did you write The God Delusion?

RD: I care passionately about the truth. I believe that the truth about whether there is a God in the Universe is possibly the most important truth there is. I happen to think it's false, but I think it's a really important question.

Also, because I felt that the world actually is drifting, parts of it anyway, towards theocracy in very dangerous ways. Education in my own field of Evolutionary Biology was under threat. There are all sorts of reasons why one might worry about the looming rise of religious influence, especially in the United States of America and in the Islamic world.

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TM: The argument from personal experience...? In late-night conversations during my high school days, my questions regarding God's existence would be answered by the challenge-defying, "You have to experience it."

RD: I think that is a difficult one, but, on the other hand, anybody who knows anything about psychology, knows what an immensely powerful simulation engine the brain is. I'm impressed by the fact that every single night of my life, my brain conjures up images and sounds of things that have never existed and never will exist. They are completely non-sensical. It's as though I go temporarily insane every night of my life and you do, too. Everybody does. We get a very life-like, full color simulation of a fantasy world inside our heads. Now, when we get that in our sleep, we call it a dream. When we get it in our waking lives -- in much less vivid form -- we might call it a vision of God or a vision of an angel, or we might say "God just talks to me."

Even when you actually see an angel or you actually hear a voice inside your head, that is an easy feat of simulation for the brain to achieve. When it's just a sort of vague feeling that God is whispering to you, it's really rather pathetic to be fooled by that, I think.