In November 2006, Mr Robertson wrote an open letter to the scientist challenging The God Delusion.

BBC: Pastor attacks scientist's talk

Some biologists, such as Richard Dawkins (author of "The God Delusion"), argue that we did not.

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Professor Dawkins is an emeritus fellow of New College, Oxford, as well as being the author of The God Delusion, and Sir David is a professor at Princeton University in the United States.

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Mr Robertson, who wrote a book, The Dawkins Letter, in response to the scientist's The God Delusion, claimed Prof Dawkins' visit was not to promote science but to "advance a polemic", or controversial argument.

BBC: Pastor attacks scientist's talk

With his latest book "The God Delusion" currently sitting comfortably among Amazon.com's top sellers and on both the New York Times and the UK's Sunday Times bestseller lists, Richard Dawkins will no doubt appreciate the irony of friends and families exchanging copies on Christmas Day.

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