Who knows?

This is the title of a book by Raymond Smullyan.

The book is about what we can and what we can't logically prove about God, alterlife, and in general religious-like stuff (like atheism).

I don't think Mr Smullyan needs introducing, but I can't let pass the chance to know if anyone here has read the book...

By the way, most of it is written in Smullyan's conversational tone, full with anecdotes and funny points.