DOCTOR: Your watch stopped. I over-compensated, ended up in the wrong time zone, ten seconds into your future.

PERI: I thought you'd been killed.

DOCTOR: You cared?

PERI: Of course I did.

DOCTOR: You know, I'll never understand the people of Earth. I have spent the day using, abusing, even trying to kill you. If you'd have behaved as I have, I should have been pleased at your demise.

PERI: It's called compassion, Doctor. It's the difference that remains between us.