Flew was a strong advocate of atheism, arguing that one should presuppose atheism until empirical evidence of a God surfaces. He has also criticised the idea of life after death, the free will defence to the problem of evil, and the meaningfulness of the concept of God. However, in 2004 he stated an allegiance to deism, and later wrote the book There is a God: How the World's Most Notorious Atheist Changed His Mind, with contributions from Roy Abraham Varghese. This book has been the subject of controversy, following an article in the New York Times magazine alleging that Flew has mentally declined, and that Varghese was the primary author. The matter remains contentious, with some commentators including PZ Myers and Richard Carrier supporting the allegations, and others—including Flew him