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        riddles >> easy >> Very Easy: Logical Signs 1
        
(Message started by: ThatGirlLooksTasty on Jan 29^th, 2003, 11:39pm)

Title: Very Easy: Logical Signs 1
Post by ThatGirlLooksTasty on Jan 29^th, 2003, 11:39pm

Sorry, I couldn't find a Logical Signs I thread. I apologize for starting this thread if there already exists another one:

Fact: One chest contains a treasure, the other contains python.
Silver Chest says: "Python in here"
Gold Chest says: "One of these is true."

Let's focus on the Gold Chest:

If the Gold Chest is true, it means that it's referring to itself, which means its the only true chest of the two, which means the Silver chest is false, which means there's no python in the Silver Chest, which means the python is in the Gold chest.

If the Gold Chest is false, it means that either both of these chests are true or both are false: If both are true, it means that the Gold chest is also true, but we just stated in this case that the Gold Chest is false. Therefore, it's a contradiction. If both are false, it also means the Silver Chest is false, which means there is no python in the silver chest.

Ultimately I would pick the silver chest... but that's just because I do not enjoy having my head ripped off. If I did enjoy getting my head ripped off, I would pick the gold chest.

Title: Re: Very Easy: Logical Signs 1
Post by prince on Jan 30^th, 2003, 3:41pm

There is, or was a thread somewhere.

The gold chest does not say ONLY one of these is true, so both chests could be true without contradiction. Unfortunately, it also doesn't necessarily gives any valid information about the silver chest.

Title: Re: Very Easy: Logical Signs 1
Post by Icarus on Jan 30^th, 2003, 4:53pm

Here is the thread for this riddle.

http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_easy;action=display;num=1027805413

You've made another assumption that is not justified: That the signs are either true or false.

If the Python is in the Silver chest, then the silver sign is true and the Gold sign is true (since, as prince points out, Golds statement does not mean only one is true).

If the Python is in the Gold chest, the silver sign is false. But the Gold sign is still not true. It is undecidable. If you assume it to be true, then yes it is true. But if you assume it to be false - guess what? it's false! Either truth value can be assigned to it without contradiction.

So my choice, if forced, would be to open the Gold chest. Much better, though to take the advice someone gives on the other thread, and find someone else to take the risk. After all, no information we are given indicates that either of the statements has to be true!

Title: Re: Very Easy: Logical Signs 1
Post by towr on Jan 31^st, 2003, 12:04am

the python is dead anyway.. (I mean, it's been in the chest without air, water, food for hundreds of years)

Title: Re: Very Easy: Logical Signs 1
Post by killian on Feb 19^th, 2003, 12:23am

I dont understand why it cant the treasure be in the bronze chest

"You know that at least one of the inscriptions is true, and at least one of the inscriptions is false."

If in the bronze chest then :

Silver Chest : Treasure is in this Chest ---- FALSE
Gold Chest : Treasure is not in this Chest ---- TRUE
Bronze Chest : Treasure is not in the Gold Chest ---- TRUE

Treasure being in the GOLD chest does not fit description :

Silver Chest : Treasure is in this Chest ---- FALSE
Gold Chest : Treasure is not in this Chest ---- FALSE
Bronze Chest : Treasure is not in the Gold Chest. ---- FALSE

Treasure Being in the SILVER chest Does not fit description :

Silver Chest : Treasure is in this Chest ------ TRUE
Gold Chest : Treasure is not in this Chest. ----- TRUE
Bronze Chest : Treasure is not in the Gold Chest ---- TRUE

So to have one inscription true and one inscription wrong , the treasure chest must be bronze

Title: Re: Very Easy: Logical Signs 1
Post by Icarus on Feb 19^th, 2003, 7:05pm

Killian - You are thinking of Logical Signs II (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_easy;action=display;num=1027937006;start=0). This thread is for Logical Signs I.