My 6 year old is a know-it-all. He has mastered the art of the declarative claim. "Dad," he'll say, "some planes can go 1000, or 24, fast." Needless to say, such claims are insane. Some are not: "Scorpion pinchers are not long enough to bite through motorcycle clothing."
It's a tone, yes, but it's also the structure of the claim — a thing, its action, a number. Sometimes, the three elements are of a type; as often, they are not. No matter. It's the affect that counts.
And this is what interests me. We learn how to make claims to knowledge as much as we learn facts per se. Learning is a matter of taking on a posture, inhabiting a pose, of making the right gestures. We learn the affect of knowing.