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Comment by mlok | Hacker News Reader

I didn't know the Liar's paradox had a name :)

Decades ago (after watching this scene from Labyrinth with David Bowie : https://youtu.be/ReFhu8KYbmU ) as a teenager I wanted to make a sentence I could use in a conversation that would always self-reference wrong. First it was "I always lie." But this (less pretty) version was more "accurate" to me :

"I always tell the opposite of the truth."

"Lie" was too vague a concept : one could argue that a lie is "relative", because it depends on subjectivity = what the subject believes is the truth. The "opposite of the truth" is more "absolute" because the subject and his beliefs/knowledge are out of the equation.

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I object to that specific incarnation because lying implies knowing the truth. Instead of lying, someone can just be incorrect.

This is why I ended up avoiding the concept of lying altogether. I explained this in my last paragraph :)

Once you have self-reference, these are pretty easy to create. I'm quite fond of such sentences that use no self-reference. E.g.

"is false when preceded by its quotation" is false when preceded by its quotation.

The above was, appropriately, first recorded by Willard Quine.

> "I always tell the opposite of the truth."

This is not a paradox though, is it? One can argue that you sometimes tell the opposite of the truth, and this is one of those times.

> I didn't know the Liar's paradox had a name :)

Liar's Paradox doesn't have a name.

Well, I used the word "always" to make sure noone can argue I sometimes tell the truth. I am not sure I understand your point.

Yes, but using "always" makes it a non-paradox. If you are someone who sometimes tells the truth you might have also said this sentence, which would make it (the sentence) simply "not true" instead of a paradox.

To disprove an universal quantification you need just a counter example of one instance, hence you are introducing an easy weakness

> Liar's Paradox doesn't have a name.

"Liar's paradox" is the "name" I discovered in this list today, to describe this kind of paradox. It has a wikipedia page, and pages in other encyclopaedias under this title. So I guess this is the most recognized name for it.

Sorry, that was a tongue-in-cheek comment, to create another paradox. I should have been more clear.

And now for something completely different: does the Liar's paradox name has a name? We know, due to the White Knight via Lewis Carroll, that e.g. the name of the song "A-sitting On A Gate" is actually "The Aged Aged Man" — are there other examples of such curious nomenclature?

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