““Amy: So. Are you proposing to someone? The Doctor: Sorry? Amy: I found this in your pocket. The Doctor: No. No no. That's a memory. Friend of mine. Someone I lost. Would you... mind. Amy: It's weird. I feel... I dunno, something. The Doctor: People fall out of the world sometimes but they always leave traces. Little things we can't quite account for. Faces in photographs. Luggage. Half-eaten meals. Rings. Nothing is ever forgotten, not completely. And if something can be remembered it can come back.””