When my political philosophy professor mentioned how he invites debate, pushback, and skepticism, I think he made a mistake...and sure enough, within an hour a kid took advantage of the invitation to make a complete ass of himself in front of the entire class.
In relation to game theory, and specifically The Prisoner's Dilemma, the professor was talking about how some societies are more cooperative are more cooperative than others, and was using his experiences in Minnesota and New Orleans as examples. He said people in Minnesota are extremely cooperative, whereas, as he put it, people in New Orleans wouldn't cooperate even if you shot them. He then went on to cite research that shows that whether we cooperate or not depends on what everyone else is doing; if everyone's cooperating, then we tend to cooperate too, and vice versa.
Then the ass raised his hand. I think you're wrong about this, he said, and I think I understand why you are wrong too. He then proposed some theory of geographical determinism, claiming that people in colder climates need to be more cooperative in order to survive the winter, and that this explains the discrepancy between Minnesota and New Orleans. Uh-huh, said the professor; that would also explain perfectly why the Russians are such cooperative people...
Of course there's nothing wrong with honest intellectual inquiry. If you see things another way, go ahead and share it. But do it in a respectful way: the classroom is no place for picking fights and trying to show how "smart" you are.
Afraid of discouraging students, professors have taken to letting this kind of arrogance go unchecked, happy that students are at least speaking. But this is dangerous. I think students may get the misconception that the rest of the world will be just as patient, leading them to an inflated ego, an argumentative personality, and a head full of empty ideas. No, students need to understand that the classroom has no room for intellectual pageantry and that there is a reason they are not lecturing themselves; the quicker they do this, the better off everyone will be.
But let's not go to the other extreme either. I am not talking about complete deference to authority and seniority. Like most things in life, being a good student requires striking a balance--in this case between independent thinking and deference. It's a difficult balance to attain, but humility (which is appallingly scant in university classrooms) makes it possible.