I noticed somebody brought up Dawkins. I'm curently reading 'The God Delusion'and thought this might be of some interest.
He shows a belief system based on the numbers 1 through 7. If you are a '1' you are a "Strong theist. 100 per cent probability of God. In the words of C. G. Jung, 'I do not believe, I know'."
Skip 2 through 5, we have 6, "Very low probability, but short of zero. De facto atheist. 'I cannot know for certain but I think God is very improbable, and I live my life on the assumption that he is not there'."
Number 7, "Strong atheist. 'I know there is no God, with the same conviction as Jung "knows" there is one."
He even goes on to say that he'd be surprised to meet very many who are in group 7.
Dawkins counts himself in category 6 where he says, "I am agnostic only to the extent that I am agnostic about fairies at the bottom of the garden."
It seems that a lot of people say atheists "know there is no God." If an atheist says that they are being just as hypocritical as some of their counterparts of religious faith who 'know' there is a God.