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0 pointsstakhanov6y ago0 comments

I have done my PhD in computational linguistics, specializing in semantics, with my thesis containing a fair chunk of work on mathematical logic, and I can assure you that presupposition is a thing!

https://en.wikipedia.org/wiki/Presupposition

It's also a thing in mathematics.

https://en.wikipedia.org/wiki/Syllogism#Existential_import

The statement "How many blue cats are bouncing" makes the presupposition that blue cats exist. That's just how language works.

It's one of those things where a formal education in mathematics will teach you to think about a thing in a way that is actually unnatural to most human beings.

The standard example that linguists use is "Do you still beat your wife?" to which you can answer neither "Yes" nor "No". Answering "Yes" means you admit that you used to beat your wife and that you are still doing it. Answering "No" means you admit that you used to beat your wife but claim that you are no longer doing it. You can only answer by escaping to the meta-level and attacking the presupposition as in "I am not currently beating my wife, nor have I ever beaten my wife". If you're a politician, then even that will get you in trouble. (Not thinking of a pink elephant, and all that, ...)

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gus_massa6y ago

I think it's perfectly fine to ask "How many bottles of milk are in the fridge?" even if there is no milk. I admit that most sane people will not answer "Zero".

If someone ask "How many elephants are in the fridge?" it would be weird.

I don't think that it is unnatural to answer "zero" in the first question, it is probably a social convention. For the second question I agree that is unnatural.

stakhanovOP6y ago

You reflected the example wrong though. Asking "How many blue cats are bouncing?" makes the presupposition that blue cats exist. "How many bottles of milk are in the fridge?" makes no presupposition of any kind. To demonstrate my point using your example: You ask: "How many of the milk bottles in the fridge are rancid?" I go to the fridge and see that there is no milk in the fridge. I now can't answer with any number at all, not even zero. Because if I say "None!" or "Zero!" then I will just have said: "I confirm that there is milk in the fridge, and state that none of it is rancid." which contradicts what I have just learned to be the truth.

This is not po-tay-to po-tah-to, people. It's a real thing.

SkyPuncher6y ago

> It's a real thing.

Most people aren't arguing this. Most people are discussing colloquial understanding of language and discussion. The differences you are arguing are important in a highly specialized area of math and science.

It feels like you're arguing whether an object is a Boeing 737 or an Airbus A320 when the important point is an airplane is not a car.

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alisey6y ago

This reminds me of vacuous truth (https://en.wikipedia.org/wiki/Vacuous_truth).

I was recently writing a function that returns early if all items in a list meet a certain condition. It was interesting to think about what should happen if that list is empty.

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