How we cite our quotes: All quotations are from The Godfather.
Quote #1
DON CORLEONE: So, Barzini will move against you first. He'll set up a meeting with someone that you absolutely trust, guaranteeing your safety. And at that meeting, you'll be assassinated.
Don Corleone is relying on pure criminal intuition here. He's going with his gut, and he's completely right. He's been around lies and deceit for so long that he can always sense the pattern. Without this advice, Michael could well have been assassinated.
Quote #2
DON CORLEONE: Listen, whoever comes to you with this Barzini meeting, he's the traitor. Don't forget that.
This is more evidence of Don Corleone's great nose for lies. Maybe it's true that only a great liar would himself be able to recognize another?
Quote #3
MICHAEL: […] Only don't tell me that you're innocent. Because it insults my intelligence and it makes me very angry. Now, who approached you first? Barzini or Tattaglia?
CARLO: It was Barzini.
MICHAEL: Good. There's a car outside that will take you to the airport. I'll call your wife and tell her what flight you're on.
Michael is deceiving Carlo, after the violent deception Carlo helped Barzini play. But there's a practical reason for this too: It makes it much easier to kill Carlo. If he thinks he's going to survive, he won't put up much of a fight. They'll be able to murder him more efficiently.