He disagrees. Nevermind repeated references to the contrary, and the existence of actual fact. My grandfather is a great, if unknowing, advocate of truthiness.
He refuses to believe that John Stewart is Jewish, but he INSISTS Colbert IS, with his entire argument based on their last names. "Stewart is a Scottish last name! He can't be Jewish! But Colbert, that's definitely a Jewish name. He's Jewish. Looks Jewish, too. Stewart doesn't look Jewish."
I mean, it matters not to me, but of all the things to mix-up concerning those two...it's hard to keep the laughter choked back while watching.