Human nature, left unchecked, can lead one to be sure of oneself far beyond what is reasonable.
Case in point:
Me (Mr. R.): "Does anyone know what is the definition of a smuggler?"
(Student raises his hand immediately.)
Mr. R.: "Now be careful. We've had a lot of kids guessing the wrong definition lately. We have talked about this. You have to learn how your brain works, and recognize what is the difference between something that you tell yourself you know and something you really do know."
(Student begins frantically windshieldwipering their hand.)
Mr. R.: "Some of you may think you know what a smuggler is, but you are only telling yourself that you know. You don't really know. It's a word that children won't run into very often, so don't raise your hand unless you have learned about smugglers and studied them. What is a smuggler?"
(Student begins to wave their hand like a castaway shipwrecked on a desert island for seven years and now sees an airplane.)
Mr. R.: "I'll call on you if you are not just guessing. Please. No guessing."
(Student begins rising out of their chair and making noises. Loud ones.)
Mr. R.: "O--K. I'll call on you, Mario, if you are absolutely positive you know the definition of a smuggler."
Mario: "I am sure, Mr. R."
Mr. R.: "O--K, Mario. What is a smuggler?
Mario: "A smuggler is a guy who dresses up in white and goes into beehives and smokes the bees with a smoking machine so that the bees will get sleepy."
As my wife, Peggy, would say, "There is a reason this child is in your classroom."