A confusing statement

If a man says 'all men are liars', is he telling the truth or is he lying?

I tried this problem, but I am getting some strange answers. When I assume that he is telling the truth, it means that all men are telling the truth, so obviously, his statement 'all men are liars' is true and he would also be a liar. If he would be a liar then the statement 'all men are liar ' would be false, it means that all men would be telling the truth, and then he would also be telling the truth, and then the process goes on.........

Note: for the time being we are assuming that either all the men is telling the truth or is lying, it cannot happen in this case that some of them would be liars and some of them would be truth tellers.

#Logic

Easy Math Editor

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Comments

I believe you want to talk about the Russell's Paradox, but there are some flaws in your logic. First, the negation of the statement "all men are liars" is "there exist a truth teller", instead of "all men are truth tellers". The question is solvable, where the man is a liar. Therefore, the statement "all men are liars" is false. In fact, there exist a man who is telling the truth.

Christopher Boo - 4 years, 8 months ago

who is the man ,(#who is telling the truth )

Syed Hissaan - 4 years, 8 months ago

i am asking not the exact same question , my question is "if a man says all men are liar , is he saying true or false "

Syed Hissaan - 4 years, 8 months ago

@Calvin Lin can you help me out in this one ?

Syed Hissaan - 4 years, 8 months ago

I think the scenario you present is equivalent to the scenario in the classical Liar's paradox.

Prasun Biswas - 4 years, 8 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$