A common accusation of atheists is that christians are irrational, preferring faith to evidence. To some christians this is not an insult, for they choose faith over logic. But other christians find this accusation both insulting and untrue, for they believe faith is based on reason and evidence.
I cannot recall anyone providing any scientific evidence for this claim. The evidence generally offered is simply that christianity involves faith, faith is not based on evidence and that is irrational.
I have just come across a book which turns this argument on its head. The Making of an Atheist by James Speigel (a professor of philosophy) argues that many atheists come to their beliefs by non-rational means. I have not read the book, but I have read parts of it and several reviews.
The book is based on scriptural teaching, but it uses evidence from psychology, the philosophy of science and atheists' own words, to establish this conclusion. The author argues that experiences in childhood, unwillingness to submit to God and immorality are all psychological factors leading to disbelief.
I'm sure there is truth in all this, although I feel some atheists I have "met" on the internet also have other, more honourable, reasons for their lack of belief in God. And I don't think I'll be using this book's conclusions to press any atheists to believe - I have objected often to atheists making unbased psychological explanations for my belief, so I don't think I should return the "compliment".
But it may be helpful to know what is in this book. At least it provides a counter to the old "christians are delusional" argument should I ever be really pressed on the matter.