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## Question

The population of the world in 2999 has been dominated by aliens. the only humans left are humans dressed as aliens. Aliens cannot lie and humans can not tell the truth. Give these factors who is whom in this situation?

A) Identifies himself to B

B) he tells C "he says he is an alien."

C) he answers B, "no he is not an alien he is a human being"

either answer is correct: ALIEN ALIEN HUMAN or HUMAN ALIEN ALIEN

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The population of the world in 2999 has been dominated by aliens. the only humans left are humans dressed as aliens. Aliens cannot lie and humans can not tell the truth. Give these factors who is whom in this situation?

A) Identifies himself to B

B) he tells C "he says he is an alien."

C) he answers B, "no he is not an alien he is a human being"

either answer is correct: ALIEN ALIEN HUMAN or HUMAN ALIEN ALIEN

Being human, I suppose I should give an incorrect answer so as not to tell the truth.

Since it's not 2999 yet, I'll stick with trying to do it right.

Congratulations for an excellent twist an old puzzle....!

Aliens and humans alike identify themselves as aliens.

B says correctly that A claimed to be an alien. So B is an alien.

C says two things.

[1] he contradicts B by saying "No." Since B was correct, we know C must be human.

[2] he says A is not alien, but human. Since C lies, A an alien.

A = alien

B = alien

C = human.

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1. Let us consider A to be human or alien.

2. If he identifies himself as B, then B cannot be human because, then, according to 1, human is telling truth, SO B IS ALIEN.

3. C denies A to be an alien. Now if A is human, C is telling truth. If A is alien, C is telling a lie. So, A and C can never be of same species. Either A-alien, C-human or A-human, C-alien.

THE RESULT IS-

A- Alien

B- Alien

C- Human

A-Human

B-Alien

C-Alien

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Being human, I suppose I should give an incorrect answer so as not to tell the truth.

Since it's not 2999 yet, I'll stick with trying to do it right.

Congratulations for an excellent twist an old puzzle....!

Aliens and humans alike identify themselves as aliens.

B says correctly that A claimed to be an alien. So B is an alien.

C says two things.

[1] he contradicts B by saying "No." Since B was correct, we know C must be human.

[2] he says A is not alien, but human. Since C lies, A an alien.

A = alien

B = alien

C = human.

Bona, C is not contradicting B becoz B is stating the claim of A not the actual state, But C is talking about the fact. So, the second answer is also correct.

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Lets make another twist---now, only one answer is possible--

A) Identifies himself to B

B) he tells C "he says he is an alien."

C) he answers B, "no he is not an alien he is a human being"

D) he says both of you (B and C) are lying.

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Bona, C is not contradicting B becoz B is stating the claim of A not the actual state, But C is talking about the fact. So, the second answer is also correct.

C's answer is: "no he is not an alien he is a human being".

My sense is that "no" only makes grammatical or logical sense if taken to be an independent statement that requires B's statement as a context.

Doing so makes A an alien.

Suppose we meet and I say

"No I am feeling fine, how are you?" or

"No it seems to be getting colder, doesn't it?" or

"No I'm seeing a movie tonight." or

"No [anything]."

What would you think the "No" means? Without context, it doesn't have a meaning.

and with context it requires a semicolon.

For C, the only available context is B's statement. Let's see how that plays out.

"no; he is not an alien..." aha! Now it makes sense.

"no" is an independent clause: a short one to be sure, but carrying the meaning:

"no, he didn't say that; he is not an alien ..." or

"no, you misquoted him; he is not an alien ..."

Making C's response two independent statements: "B is wrong; A is human"

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Lets make another twist---now, only one answer is possible--

A) Identifies himself to B

B) he tells C "he says he is an alien."

C) he answers B, "no he is not an alien he is a human being"

D) he says both of you (B and C) are lying.

We know A has said "I am alien"

B's statement is true. B is alien

C's statement is still up for grabs, I think, but let's shorten it to "A is human".

D says both B and C are lying. Thus B and C are same, so C is alien. Thus A is human, and D is human.

In C's full statement "no" has to be ignored or it's a logical mess.

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