And if you are in doubt concerning that which We have sent down (i.e. the Qur'ân) to Our slave (Muhammad Peace be upon him ), then produce a Sûrah (chapter) of the like thereof and call your witnesses (supporters and helpers) besides Allâh, if you are truthful."
(Qur'an 2:23)
https://www.youtube.com/watch?v=YfCyCRZqaGc
http://thenewkoran.blogspot.com/
http://skeptic-mind.blogspot.jp/2011/09/produce-sura-like-it.html
What if Koran was conceived in the mind of Arabic Prophet and not by God? What if he was a good philosopher and worked his way to the top?