Ariadne: Cobb can't build anymore, can he?
Arthur: I don't know if he can't, but he won't. He thinks it's safer if he doesn't know the layouts.
Ariadne: Why?
Arthur: He won't tell me. But I think it's Mal.
Ariadne: His ex-wife?
Arthur: No, not his ex.
Ariadne: They're still together?
Arthur: No, she... she's dead. What you see in there is just his projection of her.
Ariadne: What was she like in real life?
Arthur: She was lovely.