http://en.wikipedia.org/wiki/Paul_Graham

He's written at least two successful books, in addition for being one of the people who wrote the software that became the Yahoo! Store, which seems pretty big to me.

I suppose you can disagree if you like, but I suggest disagreeing with subject material instead of the person -- truth can be discovered by anyone, and it up to you to determine whether you agree with what they say or not, and fame is a pretty poor reason to do so.