# Einsteins knights and knaves

For an upcoming major puzzling event, I was honored with the task of creating one of the puzzles which will be presented. I decided to go with a variation of Einstein's puzzle. I selected four countries (Netherlands, France, Hungary and Lithuania), and invited two people from each of them.

I practiced my greetings in the respective languages before I met them, so I could give them a warm welcome. To my surprise, however, some of the guests didn't actually speak the language of the country they came from...

Well, I guess it just adds another layer to my puzzle. Luckily, it seems the languages correspond perfectly to the countries (i.e. Dutch, French, Hungarian and Lithuanian), and there are exactly two speakers of each language!

Anyway, to get to my puzzle: I decided to ask them to make a couple of statements, which would then allow the participants of the event to figure out where all of the guests came from and which languages they spoke.

In order to not give it away (and to ensure the participants could actually understand them), all the statements would be made in English. I decided to do a test round before the real event, and got the following statements:

Carl Elav: Ms. Klechter is from France
Ms. Klechter: Kifca Zagó is from the Netherlands
Prof. Iglav: I'm from the Netherlands.
Stan Elav: I know Dr. Cedric is not from Hungary
Dr. Cedric: Lisa Chever is from France.
Rita Steir: Frau Pinot is either from Hungary or Lithuania.
Kifca Zagó: I know Rita Steir is afraid of water, and thus has never been to the Netherlands.
Lisa Chever: Prof. Iglav is not from Hungary
Frau Pinot: I'm from Lithuania

... Well. It seems we have a few problems. First of all, none of the guests said anything about what language they were speaking. Secondly, we somehow ended up with 9 people speaking instead of the 8 I invited. Thirdly, I have an awful gut feeling that some of them actually weren't speaking the truth (and from experience, my gut feeling is usually pretty accurate). And last, but not least... I have a terrible memory. I don't remember which guest came from which country, or even which guest wasn't invited at all, and I lost my notes.

I've accepted the fact that we might never know where the uninvited guest came from, but I do hope that with the help of you smart people we can figure out:

• Where the other guests came from
• What language everyone speaks (including the uninvited guest)
• Who tells the truth and who is lying

It might seem like an impossible task, but my gut feeling tells me there should be some people here who should be able to do it. Please show me my gut feeling is right again - I'd love to present it at the event!

• "upcoming major puzzling event" - What? Where? When? I need details!! :P – Sid Mar 2 '18 at 13:22
• @Sid : in Lithuania. Or Holland. Or France. Or Hungary. – Evargalo Mar 2 '18 at 13:23
• @Sid It's a closed event unfortunately, but maybe if you happen to solve my conundrum I'd be able to get you an invite :P – Lolgast Mar 2 '18 at 13:23

I'm still not quite sure about some parts, but I think the final solution is:

    guest           is a      speaks        comes from
------------    ------    ----------    -------------
Carl Elav       knight    Catalan*      Mystery
Ms. Klechter    knave     Dutch         France
Prof. Iglav     knight    Hungarian     Netherlands
Stan Elav       knave     Lithuanian    Lithuania*
Dr. Cedric      knight    Dutch         Hungary
Rita Steir      knight    Lithuanian    Netherlands*
Kifca Zagó      knave     Hungarian     Lithuanian
Lisa Chever     knight    French        France
Frau Pinot      knave     French        Hungary

(Parts I'm uncertain about are marked with asterisks. I'll explain below.)

First, the languages and the truthfulness of the guests:

It is clear that this is not a regular Einstein puzzle. The statements are exclusively about the countries of origin of the guests. And how can we assign peferred language, knighthood and knaveship? In particular, how can we know the language of the mystery guest?

There is an enigmatic component to the puzzle. The names of the guests are peculiar and raise suspicion. It turns out that each of the names is a near-anagram of either "knight" or "knave" in one of the four given languages plus one anagram in an unknown language. For each language, there is one knave and one knight.

Carl Elav: cavaller (Catalan for knight)
Ms. Klechter: schelm (Dutch for knave) + kter
Prof. Iglav: lovag (Hungarian for knight) + fipr
Stan Elav: valetas (Lithuanian for knave) + n
Dr. Cedric: ridder (Dutch for knight) + cc
Rita Steir: riteris (Lithuanian for knight) + at
Kifca Zagó: gazfickó (Hungarian for knave) + a
Lisa Chever: chevalier (French for knight) + s
Frau Pinot: fripon (French for knave) + uat

(I'm not quite sure about the significance of the leftover letters and why there are different amounts for each word. Only cavaller is a proper anagram. The Romanian word calavel would leave one ell unused. The excess letters also makes assigning words to languages difficult. For example, one possibility to say knave in French is valet, which clashes with the Lithuanian word.)

Now the countries of origin. Over to you, Einstein!

Now that we know which of our guests speaks the truth, we can adjust the knaves' statements (in italics) accordingly:

Carl Elav: Ms. Klechter is from France
Ms. Klechter: Kifca Zagó is NOT from the Netherlands
Prof. Iglav: I'm from the Netherlands.
Stan Elav: I know Dr. Cedric is not from Hungary
Dr. Cedric: Lisa Chever is from France.
Rita Steir: Frau Pinot is either from Hungary or Lithuania.
Kifca Zagó: I know [...] Rita Steir has never been to the Netherlands.
Lisa Chever: Prof. Iglav is not from Hungary
Frau Pinot: I'm NOT from Lithuania

Some of the statements are write-ins: Ms. Kletcher and Lisa Chever are from France; Prof. Iglav is from the Netherlands; Dr. Cedric and Frau Pinot are from Hungary. The mystery guest must be Carl Elav, who doesn't speak any of the four languages of the invited guests. That leaves the two Stan Elav, Rita Steir and Kifca Zagó unaccounted for; two of them are from Hungary, one is from the Netherlands.

What to make of Kifca Zagó's statement? It it were true, it would rule out that Rita Steir is from the Netherlands. But which part of the rather arcane sentence is a lie? Has Rita never been to the Netherlands and Kifca doesn't know about this? Or has she never been to the Netherlands, but not because she's afrais of water? Or has she been to the Netherlands, which doesn't say anything at all whether she lives there. This sentence is not very useful.

The only other statement that hasn't been used is the one that says that Kifca Zagó is not from the Netherlands, which means that Kifca is from Lithuania.

I'm not really sure how to determine which of the two remaining persons, Stan Elav and Rita Steir, comes from the Netherlands and who from Lithuania, so I'll just assume that the negation of the knavish Kifca's statement means that Rita come from the Netherlands.

And ...

... I still don't know whether the excess letters have a meaning. The puzzle says that we might never know where the ninth guest comes from, but I'm uneasy: Can the letters be used to find out where Carl is from? The extra leters arenÄt really needed to make good names. For example, Dr. Cedric might just have been Dr. Reid. Hmmm ...

• Thanks for helping me out! I guess it's no big deal we don't know where our 9th guest comes from, and I don't think we'll be able to figure it out. I'm thinking Kifca is just being unnecessarily complicated, he probably just means to say that Rita is not from the Netherlands, leaving your analysis complete. I've contacted the person responsible for sending out invitations to the event, but it seems they're all given out already :/ – Lolgast Mar 2 '18 at 18:12
• (Out of role-playing: The extra letters are just for obfuscation. Unless you happen to find a perfect solution for them of course - then I'll be happy to pretend that was totally intended!) I'll accept your answer in a bit. – Lolgast Mar 2 '18 at 18:13
• I think one of the Elavs is the extra guest, probably Carl, as he is the only one who doesn't have a corresponding language partner, and might have been brought along by Stan – Peregrine Lennert Mar 2 '18 at 19:02