I just don't get it

[Old Baby]

This might have been discussed before, but I'm really unable to understand it.

Today I've been discussing atheism with my friends (Muslims) and believe me, they're quite intelligent. At any rate, after I gave them plenty of strong arguments and cornered them, all they could say was " I believe deep down that there is a god".

Now this got me thinking (which is strange now that I think about it, since I've listened to this argument countless of times before and this has been discussed very often on these forums)

What kind of process that led me to become an atheist, that for some reason did not occur to them? I'm not a special snowflake for pit sakes.

I think intelligence is not the issue here, I know I can't convince you guys, but these friends of mine are really scientifically versed. Richard Dawkins, and many others, often said that these people are stuck in some kind of "child stage". 

I think it has to do with their "character", but I am very hesitant to say that, since I wouldn't consider myself to be a courageous person. In fact, I've had atheist friends who were particularly shy and introvert.

So what gives?

I was of the same mind at one time.  My mind was just closed.  It's not that I willed it closed or was in denial.  I just knew that I knew that I knew, as Christians said.  Until I eventually stopped and opened my mind up to the possibility that there could be cracks in the dogma, there was no way for any light to come through.  It simply doesn't matter how powerful your arguments are.  I'm finding this out now, discussing religion with a casual Christian friend of mine.  She is interested, but no matter how damning my evidence is, she just files it away.  It seems to prove itself out that those who are deeper in Christianity and have spent more time with the bible, such as clergy or those who are studying to be, are the ones who are able to break free the easiest.  To those "casuals" who are less studied (perhaps less intelligent?), good luck ever getting them to open their minds.