The Cool....as an elusive essence

A piece of Simpsons dialogue (from the episode Homerpalooza)....

Homer: So, I realized that being with my family is more
important than being cool.
Bart: Dad, what you just said was powerfully uncool.
Homer: You know what the song says: "It's hip to be square".
Lisa: That song is so lame.
Homer: So lame that it's... cool?
Bart+Lisa: No.
Marge: Am I cool, kids?
Bart+Lisa: No.
Marge: Good. I'm glad. And that's what makes me cool,
not caring, right?
Bart+Lisa: No.
Marge: Well, how the hell do you be cool? I feel like
we've tried everything here.
Homer: Wait, Marge. Maybe if you're truly cool, you
don't need to be told you're cool.
Bart: Well, sure you do.
Lisa: How else would you know?