Niles: Frasier, where are your ethics? You can't date someone who's involved with one of your patients.
Frasier: Marco is not a patient, he's a caller. There's a huge difference. I talked to him days before I met her.
Niles: Rationalization, the last refuge of an unsound argument.
[Both argue at the same time]
Frasier: Oh, Niles, I am not rationalizing. There is nothing wrong here.
Niles: As long as your conscience is clear. I'm not sure mine wouldn't be.
Frasier: Well, frankly, I don't care about your conscience. And I don't need your approval. I don't need you to like it. In fact, I don't need you for anything. Oh, by the way, Niles, my car's in the shop. I need you to give me a ride home tonight.
Niles: No problem.