Who are excessively talkative? You never see intelligent people shoot their mouths off about pointless nothings or ramble about their entire life to people that so obviously don't give a damn and just want to get on with their day as planned. Smart people don't trap you while you're going along, minding your own business, and hijack your time so that they have an excuse to flap their lips off about nothing important. Smart people don't interrupt your day for no less than a half hour at a time to verbally dribble at you. No, smart people often keep to themselves, and maybe offer a friendly "hello" to maintain neighborhood morale. That's about it. You never see a smart person ask favors of their socially reluctant neighbors who are basically strangers, since they never have an opportunity to get a word out. Only a stupid or crazy person would ask their new neighbors to do some grocery shopping for them after they just came home from a long day at work. The nerve! Only stupid people have such nerve. Only a stupid person wouldn't know that after all the accumulative hours they've spent gabbing needlessly at someone, that that someone would never go out of their way to pick up your cat's litter even if you paid them.
The worst thing is that stupid people are convinced that they're smart.