When John Sullivan’s grandmother heard he’d left the Christian faith, she sent him a 33-page letter “with a dismissal of evolution on theological grounds.” He’s now posted his response online—a long letter of his own, filled with figures and data and ending with this:

I expect you to agree with a few points and to firmly disagree with others (I do expect that you will respond), but above all I expect that nothing I have said changes our relationship or the interest we both take in approaching these usually sensitive subjects. I love you! Thanks for reaching out to me and thank you for spending time to understand where I am and how I got here.

“Bravo!” says PZ Myers. “This is how loving families should deal with faith, by simply caring enough to wrestle with the ideas between them.”