Sir Humphrey: With Trident we could obliterate the whole of Eastern Europe.
Jim Hacker: I don't want to obliterate the whole of Eastern Europe.
Sir Humphrey: It's a deterrent.
Jim Hacker: It's a bluff. I probably wouldn't use it.
Sir Humphrey: Yes, but they don't know that you probably wouldn't.
Jim Hacker: They probably do.
Sir Humphrey: Yes, they probably know that you probably wouldn't. But they can't certainly know.
Jim Hacker: They probably certainly know that I probably wouldn't.
Sir Humphrey: Yes, but even though they probably certainly know that you probably wouldn't, they don't certainly know that, although you probably wouldn't, there is no probability that you certainly would.