User blog comment:Icehard712/Nerd fight, anyone?/@comment-11643042-20150214045139

Now for Dipper's real name.

Alright, put yourself in this kid's shoes. He has an embarrassing birthmark which, as Dipper admitted himself, he hides all the time under his hair. The name Dipper is a constant reminder of that birthmark. So, if he had another name, don't you think he would go by that name? The only reason I can think of why he wouldn't is if that name was even more embarrassing.