How smart are you?

I just overheard someone on the phone ask "Hey Joe. You're a smart guy, right?"

Now how would someone respond to that?

"Well actually I am not very smart Susie. You see I don't even know what this thing I am using to talk with is called....a snorkel? How does it work? Are you trapped inside of it? Hello Susie? My third grade teacher told me I wasn't going to amount to much but I didn't really have time to listen because I was too busy gluing pencils to onto my elbows. I can't really talk now Susie I need to go make a peanut butter and jelly shoehorn. It's going to take quite some time to find the recipe on Google because I don't know if shoehorn is a compound word or not."