If I said to you...

TNGL · 25 Sep 2018 at 00:08

If I said to you that I always lie. Am I a liar or am I not?

After all, I am telling the truth about being a liar... But if I am telling the truth, I am not a liar... Now I have lied about being a liar.

Thoughts?

Interested to see how GD's wisdom tackles the liar's paradox.

TNGL · 26 Sep 2018 at 23:57

Reworded the OP to remove the ambiguity. At one point I thought somebody was going to enter their boxing stance over the wording.

TNGL · 29 Sep 2018 at 19:00

I do not think the example given of the liar's paradox in the OP has been understood. What if it was presented in the form of:

"This sentence is false"

There is no sometimes, selectiveness, occasionally etc to be had in this instance.

TNGL · 30 Sep 2018 at 11:49

muon said:
But that's not referring to something real so isn't a paradox.

What?

touch said:
That's essentially what the OP was before it was edited.

This example is more black and white in that it is clear you cannot have a solution that makes use of words such as occasionally or sometimes.

TNGL · 30 Sep 2018 at 12:40

muon said:
a = b and b > a.

Paradox! Except there is nothing intrinsic about what I've said so isn't a paradox.

I see what you're getting at but I wouldn't apply that same logic here.

You have two statements, a = b and b > a. I have merely stated (where B is 'this sentence'):

A = True (if B = False), however, if A = True then B ≠ False. This is where the contradiction comes into play. I have not proposed "This sentence is false" and "This sentence is true", I am only proposing "This sentence is false".