TheCodeCrack,

Most Swedes are atheists, they just don't know the word for it. I would not really claim they are more intelligent than other people, it's just that we are not indoctrinated with religion as much as others. I'm not particularly intelligent myself either, I just happen to find this topic extremely interesting and being drawn to skepticism it's easy to see why superstitions are wrong. It doesn't necessarily take intelligence to see that, it just needs you to not have been indoctrinated with lies, but with science.

If high intelligence was of need to become an atheist, what chances do we have in converting people (if that is ones will, of course)?

I have come to believe the best way is to teach skepticism. Most people will agree that it's sensible, and then they might apply it to their own faith.