ROBOT: You have been examining it for 2.36 minutes. Logic circuits dictate you wish to buy the book.

DOCTOR: I happen to be browsing!

ROBOT: ‘Browsing’ — that word is not in my database.

DOCTOR: Why did I know you were going to say that...? All right, fine, I’m buying the book. You do take Alpha Centauri express, I take it?

ROBOT: That will do nicely, sir.

(FX: Electronic till sound)

DOCTOR: You, my metal friend, are an electronic mugging machine.

ROBOT Would you like to consider other related titles, sir?

DOCTOR: No, I think ‘electronic mugging machine’ will quite suffice.