THAMUS: It's ready, sire. What do you think?
KING: Oh, excellent. I'm sure it's a fantastic door. There's nothing a dwarf likes more than a good sturdy door - except mining, hating elves, beards, axes, and actually liking elves quite a lot after all.
THAMUS: Yep, they're my top 5, too.
KING: Haha! Capital. So, Thamus, may I have the key?
THAMUS: No, my lord. There is no key.
KING: No key? Thamus, I may not know much about doors...but actually, I do, in fact, know an awful lot about doors, and I know a door has to have a key.
THAMUS: Not this one. Up the top, above the door, it says "Speak, friend, and enter".
KING: So, your mate's got the key?
THAMUS: No, sire, it's a magical lock. Imagine you're trying to open it. Do what it says.
KING: Speak?
THAMUS: Yes.
KING: Err, hello, door. Open up. Chop chop, come on, shake a hinge. I'm king you know/
THAMUS: Aha! Now, imagine if the word you were to speak were to be the word "friend", the door just might open.
KING: Friend?
THAMUS: That's the one. The clue was right there all along! Clever, don't you think?
KING: No it wasn't.
THAMUS: Speak, friend, and enter.
KING: Doesn't make any sense.
THAMUS: No, it's like a joke. What it is, you see, is-
KING: No, I get it, Thamus. But it doesn't work. "Say friend and enter", that would work - well, with the minor addition of some inverted commas - but speak friend? Absolute garbage. It's not idiomatic. It's a shit joke.
THAMUS: I think it works.
KING: It definitely does not.
THAMUS: Ah, well, it doesn't matter, really. The inscription won't be in English.
KING: What's English?
THAMUS: What we're speaking now. What's spoken by all men, and hobbits, and barrow wights, and giant spiders, and bear people, and orcs sometimes it's not consistent.
KING: Oh, yes. And we're speaking it now, apparently.
THAMUS: That's right. It was also called Galactic Basic Standard, a long time ago. So, yes, the inscription isn't in English, it's in Dwarfish, where there's no ambiguity. Everyone will know what it means.
KING: Really?
THAMUS: Oh, yes, deinfitely.
KING: We might as well leave the bloody door open, then.
THAMUS: No, no, only people who can speak Dwarfish will know it. And, you know, our enemies can't do that.
KING: Course they can! If you were planning on invading a whole people, I'm sure that you could find someone in your vast phalanx of warriors who could learn the language.
THAMUS: Ooh, I dunno, it's hard work learning a language.
KING: Thamus, there are loads of wolves down the hill there that have learnt to talk.
THAMUS: English?
KING: Coincidentally, yes. And if wolves can do it, I'm sure a highly organised enemy can find a single person.
THAMUS: So, do you want me to change the door, then?
KING: Yes.
THAMUS: Alright, you're the king. But I will miss the engravings.
KING: Engravings? Why didn't you say? Engravings are my sixth most favourite thing! I think a little bit of lax security is worth it for some good engravings. We shall keep your wondrous door, Thamus.
THAMUS: Hooray! Err, and, sire, here's my bill.
KING: Oh, yes, fine, fine. Speak to the treasury.
THAMUS: "To the treasury". [Beat] Oh, sorry, that happens to me a lot.