They don't find teachers who believe in them. They get convinced they are stupid.

Sean: My wife used to fart when she was nervous. She had all sorts of wonderful little idiosyncrasies. She used to fart in her sleep. I thought I’d share that with you. One night it was so loud it woke the dog up. She woke up and went ‘ah was that you?’ And I didn’t have the heart to tell her. Oh!
Will: She woke herself up?
Sean: Ah...! But Will, she’s been dead for 2 years, and that's the shit I remember: wonderful stuff you know? Little things like that. Those are the things I miss the most. The little idiosyncrasies that only I know about: that's what made her my wife. Oh she had the goods on me too, she knew all my little peccadilloes. People call these things imperfections, but there not. Ah, that's the good stuff.

~ Robin Williams as Sean Maguire, Matt Damon as Will Hunting.

Sean: Real loss is only possible when you love something more than you love yourself.

[ordering drinks]
Lambeau: Perrier.
Sean: That's French for "club soda."

Will (Voice over): Sean, if the professor calls about that job tell him sorry, but I had to go and see about a girl.
Sean: Son of a bitch, he stole my line.

Will: I didn't ask for this.
Sean: No, you were born with it. So don't cop out behind 'I didn't ask for this.'