Do you know WikiIslam ?

[Angrboda]

The "science of the hadith" was the same process that gave you magic book.  You and I have discussed this before, and iirc you and I were together in mentioning to winter that if the game of telephone couldn't be trusted for hadith, it couldn't be trusted for magic book either.  Up to and including any notion....as told in the narrative chain certified by this vry srs science..that magic book is inerrant.  

That's true. But believing in a miracle because it's reported in the Qur'an is not the same as believing in it because we trust the chain of narrators of that particular event. A Muslim has independent reasons to believe that the Qur'an is God's words, and the Qur'an says an event E happened, therefore the Muslim believes that E happened. No need to investigate who was there when E took place.

What are those independent reasons?