You know, I've never been fond of the idea that your character stats and ability to use spells is tied in with your personality.  There's nothing wrong with being a ditzy cleric, clueless wizard, or shy sorcerer, except that playing it "by the book" means you end up being horribly ineffective for it.  So you either have to suck it up and play a smart wizard, play a silly foolish wizard with an int of 10, or say screw the rules, play whatever personality you want, and not care that it doesn't go by the numbers written on your character sheet.