Survey reveals atheists and agnostics test better than their more decidedly religious brethren.

[glitch25]

http://religion.blogs.cnn.com/2010/09/28/dont-know-much-about-religion-youre-not-alone-study-finds/?hpt=Sbin

I wonder if part of this is that a lot of folks who don't come by agnosticism and atheism naturally (as suggested by the survey), are more apt to question and research the material in their struggle to find their own truths, rather than "take it on faith."