Knights and Knaves question
$begingroup$
You are on a land inhabited by Knights and Knaves. Knights will always tell the truth and knaves always lie.
You meet three inhabitants(A, B, and C), and ask how many of them are knaves. A answers so quietly, so you ask B what A had said. B says that A had said that exactly two of them were knaves. C says B is lying.
Is it possible to know what A is?
Further, what are B and C.
logical-deduction liars
asked 5 hours ago
user58804user58804
263
New contributor
user58804 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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add a comment |
$begingroup$
You are on a land inhabited by Knights and Knaves. Knights will always tell the truth and knaves always lie.
You meet three inhabitants(A, B, and C), and ask how many of them are knaves. A answers so quietly, so you ask B what A had said. B says that A had said that exactly two of them were knaves. C says B is lying.
Is it possible to know what A is?
Further, what are B and C.
logical-deduction liars
asked 5 hours ago
user58804user58804
263
New contributor
user58804 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
3
$begingroup$
Please don't change your question after someone has answered it. Now the answer references D, E, and F, and makes no sense. I'm editing the answer to match the revised question, but in the future it's best not to make changes that make the answers obsolete ... especially when the changes are superficial like this.
$endgroup$
– Rubio♦
3 hours ago
add a comment |
$begingroup$
You are on a land inhabited by Knights and Knaves. Knights will always tell the truth and knaves always lie.
You meet three inhabitants(A, B, and C), and ask how many of them are knaves. A answers so quietly, so you ask B what A had said. B says that A had said that exactly two of them were knaves. C says B is lying.
Is it possible to know what A is?
Further, what are B and C.
logical-deduction liars
asked 5 hours ago
user58804user58804
263
New contributor
user58804 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
You are on a land inhabited by Knights and Knaves. Knights will always tell the truth and knaves always lie.
You meet three inhabitants(A, B, and C), and ask how many of them are knaves. A answers so quietly, so you ask B what A had said. B says that A had said that exactly two of them were knaves. C says B is lying.
Is it possible to know what A is?
Further, what are B and C.
logical-deduction liars
logical-deduction liars
asked 5 hours ago
user58804user58804
263
New contributor
user58804 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 5 hours ago
user58804user58804
263
New contributor
user58804 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 4 hours ago
user58804
asked 5 hours ago
user58804user58804
263
New contributor
user58804 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 5 hours ago
user58804user58804
263
asked 5 hours ago
user58804user58804
263
263
New contributor
user58804 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
user58804 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
user58804 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
3
$begingroup$
Please don't change your question after someone has answered it. Now the answer references D, E, and F, and makes no sense. I'm editing the answer to match the revised question, but in the future it's best not to make changes that make the answers obsolete ... especially when the changes are superficial like this.
$endgroup$
– Rubio♦
3 hours ago
add a comment |
3
$begingroup$
Please don't change your question after someone has answered it. Now the answer references D, E, and F, and makes no sense. I'm editing the answer to match the revised question, but in the future it's best not to make changes that make the answers obsolete ... especially when the changes are superficial like this.
$endgroup$
– Rubio♦
3 hours ago
3
3
$begingroup$
Please don't change your question after someone has answered it. Now the answer references D, E, and F, and makes no sense. I'm editing the answer to match the revised question, but in the future it's best not to make changes that make the answers obsolete ... especially when the changes are superficial like this.
$endgroup$
– Rubio♦
3 hours ago
$begingroup$
Please don't change your question after someone has answered it. Now the answer references D, E, and F, and makes no sense. I'm editing the answer to match the revised question, but in the future it's best not to make changes that make the answers obsolete ... especially when the changes are superficial like this.
$endgroup$
– Rubio♦
3 hours ago
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
It's not possible to know what A is.
C says B is lying. So either C is a knave and B is a knight or C is a knight and B is a knave. Therefore there is one knave among (B,C).
Assume A is a knave. Then there are 2 knaves and A would lie about it. Therefore B is lying about what A said, so A, B are knaves and C is a knight.
Assume A is a knight. Then there is only one knave and B is lying about what A said, so A, C are knights and B is a knave.
In both scenarios B is a knave and C is a knight. A could be either a knight or a knave.
edited 3 hours ago
Rubio♦
30.8k667189
answered 5 hours ago
JayJay
2,8942922
$endgroup$
add a comment |
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1 Answer
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1 Answer
1
active
oldest
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active
oldest
votes
active
oldest
votes
$begingroup$
It's not possible to know what A is.
C says B is lying. So either C is a knave and B is a knight or C is a knight and B is a knave. Therefore there is one knave among (B,C).
Assume A is a knave. Then there are 2 knaves and A would lie about it. Therefore B is lying about what A said, so A, B are knaves and C is a knight.
Assume A is a knight. Then there is only one knave and B is lying about what A said, so A, C are knights and B is a knave.
In both scenarios B is a knave and C is a knight. A could be either a knight or a knave.
edited 3 hours ago
Rubio♦
30.8k667189
answered 5 hours ago
JayJay
2,8942922
$endgroup$
add a comment |
$begingroup$
It's not possible to know what A is.
C says B is lying. So either C is a knave and B is a knight or C is a knight and B is a knave. Therefore there is one knave among (B,C).
Assume A is a knave. Then there are 2 knaves and A would lie about it. Therefore B is lying about what A said, so A, B are knaves and C is a knight.
Assume A is a knight. Then there is only one knave and B is lying about what A said, so A, C are knights and B is a knave.
In both scenarios B is a knave and C is a knight. A could be either a knight or a knave.
edited 3 hours ago
Rubio♦
30.8k667189
answered 5 hours ago
JayJay
2,8942922
$endgroup$
add a comment |
$begingroup$
It's not possible to know what A is.
C says B is lying. So either C is a knave and B is a knight or C is a knight and B is a knave. Therefore there is one knave among (B,C).
Assume A is a knave. Then there are 2 knaves and A would lie about it. Therefore B is lying about what A said, so A, B are knaves and C is a knight.
Assume A is a knight. Then there is only one knave and B is lying about what A said, so A, C are knights and B is a knave.
In both scenarios B is a knave and C is a knight. A could be either a knight or a knave.
edited 3 hours ago
Rubio♦
30.8k667189
answered 5 hours ago
JayJay
2,8942922
$endgroup$
It's not possible to know what A is.
C says B is lying. So either C is a knave and B is a knight or C is a knight and B is a knave. Therefore there is one knave among (B,C).
Assume A is a knave. Then there are 2 knaves and A would lie about it. Therefore B is lying about what A said, so A, B are knaves and C is a knight.
Assume A is a knight. Then there is only one knave and B is lying about what A said, so A, C are knights and B is a knave.
In both scenarios B is a knave and C is a knight. A could be either a knight or a knave.
edited 3 hours ago
Rubio♦
30.8k667189
answered 5 hours ago
JayJay
2,8942922
edited 3 hours ago
Rubio♦
30.8k667189
edited 3 hours ago
Rubio♦
30.8k667189
edited 3 hours ago
Rubio♦
30.8k667189
30.8k667189
answered 5 hours ago
JayJay
2,8942922
answered 5 hours ago
JayJay
2,8942922
answered 5 hours ago
JayJay
2,8942922
2,8942922
add a comment |
add a comment |
user58804 is a new contributor. Be nice, and check out our Code of Conduct.
user58804 is a new contributor. Be nice, and check out our Code of Conduct.
user58804 is a new contributor. Be nice, and check out our Code of Conduct.
user58804 is a new contributor. Be nice, and check out our Code of Conduct.
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3
$begingroup$
Please don't change your question after someone has answered it. Now the answer references D, E, and F, and makes no sense. I'm editing the answer to match the revised question, but in the future it's best not to make changes that make the answers obsolete ... especially when the changes are superficial like this.
$endgroup$
– Rubio♦
3 hours ago