Welcome Guest [Log In] [Register]
Add Reply
  • Pages:
  • 1
  • 11
Puzzle #13; The Three Gods
Topic Started: Jul 8 2009, 07:48 PM (4,556 Views)
Don Paolo
Member Avatar
Administrator
Three gods A, B, and C are called, in some order, True, False, and Random. True always speaks truly, False always speaks falsely, but whether Random speaks truly or falsely is a completely random matter. Your task is to determine the identities of A, B, and C by asking three yes-no questions; each question must be put to exactly one god. The gods understand English, but will answer all questions in their own language, in which the words for yes and no are 'da' and 'ja', in some order. You do not know which word means which.

* It could be that some god gets asked more than one question (and hence that some god is not asked any question at all).
* What the second question is, and to which god it is put, may depend on the answer to the first question. (And of course similarly for the third question.)
* Whether Random speaks truly or not should be thought of as depending on the flip of a coin hidden in his brain: if the coin comes down heads, he speaks truly; if tails, falsely.
* Random will answer 'da' or 'ja' when asked any yes-no question.
Offline Profile Quote Post Goto Top
 
Darkstar Runner
Member Avatar
That Crazy Lady
Argh! Dang it! I remember seeing that riddle somewhere quite recently...but I can't remember the answer...
Offline Profile Quote Post Goto Top
 
TheUncleBob

No.
Edited by Don Paolo, Jul 8 2009, 07:54 PM.
Offline Profile Quote Post Goto Top
 
ndef

Do all three gods speak the same language? (If "Ja" means "Yes" to one god, does that mean that "Ja" means "Yes" to all the gods?)
Offline Profile Quote Post Goto Top
 
TheUncleBob

I, personally, always like the "Exploding Heads" solution. Ask each of the three Gods the following question: "Will you answer this question with the word that means "no" in your language?" (This would be all three of your questions).

The God that tells the truth cannot answer - if he says "No", then he's lying. If he answers "Yes", then he's lying.

The God that always lies must answer "Yes", otherwise, he'll tell the truth.

The random God, of course, can do whatever he wants - so you won't actually solve the puzzle. But you made the first God's head explode, and that's more fun.
Offline Profile Quote Post Goto Top
 
Don Paolo
Member Avatar
Administrator
ndef
Jul 8 2009, 08:01 PM
Do all three gods speak the same language? (If "Ja" means "Yes" to one god, does that mean that "Ja" means "Yes" to all the gods?)
Yes
Offline Profile Quote Post Goto Top
 
ndef

When there are just two gods, True and False, then the trick is to ask one of them what the other would say. So, ask A if B would call himself "True." Then, you know the answer A gives you is false, because either he's lying or he's reporting the false information B would give.

So, maybe the trick is to identify Random within 2 questions, and then use this method to figure out which of the remaining two is True and which is False.
Offline Profile Quote Post Goto Top
 
wedge

TheUncleBob
Jul 8 2009, 08:02 PM
I, personally, always like the "Exploding Heads" solution. Ask each of the three Gods the following question: "Will you answer this question with the word that means "no" in your language?" (This would be all three of your questions).

The God that tells the truth cannot answer - if he says "No", then he's lying. If he answers "Yes", then he's lying.

The God that always lies must answer "Yes", otherwise, he'll tell the truth.

The random God, of course, can do whatever he wants - so you won't actually solve the puzzle. But you made the first God's head explode, and that's more fun.
while certainly not a sure fire way of answering, you could always hope for the best that if by asking the question 3 times that if one changes his answer then you know which is Random.

but being random he could say the same answer 3 times...
Offline Profile Quote Post Goto Top
 
Uohz

I'm running into a a wall. I can't figure out how to eliminate the Random from the problem in the first 2 questions.

Edit again: Nevermind, I just reworked my solution. I can determine which god is True and which is False with 1 question, but only if Random isn't involved. Someone work on ascertaining Random in 2 questions. I need to eat lunch.
Edited by Uohz, Jul 8 2009, 08:25 PM.
Offline Profile Quote Post Goto Top
 
Nek'rahm

Will Random answer the same question with the same answer, or will his answers be random?

i.e. if you ask him twice if he is True, could he answer "Ja" and "Da" to you?
Offline Profile Quote Post Goto Top
 
1 user reading this topic (1 Guest and 0 Anonymous)
Go to Next Page
« Previous Topic · Puzzle HQ · Next Topic »
Add Reply
  • Pages:
  • 1
  • 11

Theme created by tiptopolive. Find more great themes and skins at the ZB Theme Zone.