I can normally tell how intelligent a man is by how stupid he thinks I am.
Man is so intelligent that he feels impelled to invent theories to account for what happens in the world. Unfortunately, he is not quite intelligent enough, in most cases, to find correct explanations. So that when he acts on his theories, he behaves very often like a lunatic.
Ninety-nine percent of everything that goes on in most Christian churches has nothing whatsoever to do with the actual religion. Intelligent people all notice this sooner or later, and they conclude that the entire one hundred percent is bullshit, which is why atheism is connected with being intelligent in people's minds.