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ColinWright

I read statement "All my hats are green" as meaning:

For every hat H that I have, H is green.

If I have no hats, this statement is true, just as

* the empty sum is 0,

* the empty product is 1,

* the empty AND is True, and

* the empty OR is False.

So with this interpretation, the liar having no hats would make the statement true.

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by the same following, this would mean that any statement on the members of an empty set can be made and it would be logically true?

e.g. "all my lamborghinis have magical goat skin seat covers" is true if 1) I have no lamborghinis or 2) All the ones I own have magical goat skin seat covers.

(fr I have no logical or mathematical background)

Correct.

Common source of confusion/trickery/divergence between ordinary language and formal logic.

Edit: Logically speaking, the following two are equivalent:

They married and had kids.

They had kids and married.

Also I think sometimes children will realize a logic gap there and so they will try this funny trickery where they will make statements like these, which technically are true, but imply something totally otherwise to others. Which I find very interesting and kind of speaks to ability and inventiveness of children to think outside the box. Parents may find it annoying or dismiss it, but I think it is great.

vacuous truths are indeed a useful form of half-truth if you are aiming to deceive.

> Edit: Logically speaking, the following two are equivalent:

Depends on your logical system! There are temporal logics to allow one to capture logically the difference between the two.

I don't have formal logic or any math beyond calculus, either, and it appears that this fact is to our advantage.

You don't need to have learned formal logic to conclude the answer to this puzzle in my view. Yes, formal logic concludes it, but plain logic as well. The key is to realize that the answer will go against your learned social intuition and be fine with that. Social communication in many cases is illogical for efficiency reasons and that is fine. It is interesting to point out those cases and make puzzles out of them.

I agree.

I would appreciate it if you would correct my thinking on the subject, if I have erred: https://news.ycombinator.com/item?id=42365506

Thanks in advance.

Yes, your statement would be true.

Yes

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