Comment by kazinator | Hacker News Reader

Comment by kazinator | Hacker News Reader

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A complete stranger who has nothing whatsoever to do with you, who has never tried to do anything for you, nor has been expected to, has never disappointed you. They've also never failed to disappoint you, because they have not failed in any regard whatsoever.

This is an example of a vacuous truth.

I've never failed an airliner landing. While that may sound like I'm boasting of being a good pilot, in fact I'm not a pilot at all, and I've never attempted such a thing.

Another vacuous truth.

Every crow in an empty set of crows is white.

Also, every crow in an empty set of crows is black.

Propositions universally quantified over an empty set are all vacuously true.

Statements with always and never are universally quantified over some set of events. If that set is empty it leads to vacuous truths.

"Every time I've seen a crow, it has always been white" is vacuously true if I've never seen a crow. I.e. the set of crows I've seen is empty, and consequently is a true statement that they're all white.

> A complete stranger who has nothing whatsoever to do with you, who has never tried to do anything for you, nor has been expected to, has never disappointed you. They've also never failed to disappoint you, because they have not failed in any regard whatsoever.

Nobody who uses the phrase ever means it in this way. The point of using the statement is to convey that you are familiar with the person’s history.

As another commenter has already pointed out, “has never failed to disappoint” is not the same statement as “never fails to disappoint”. The habitual present can’t refer to empty sets, as it is only used to refer to repeated actions.

> Nobody who uses the phrase ever means it in this way.

That is true. Outside of formal logic situations, deliberately uttered vacuous truths are only ever used by nerds to be clever, or for sarcasm, or insult and such.

Someone habitually using "never fails to disappoint" intended as a compliment has somehow latched onto an incorrect idiom; they likely intend something slightly funny like "never manages to disappoint" (tries hard to disappoint, but never does, due to being so good!). Or maybe it's supposed to be a deliberately funny mixup of "never fails" and "never disappoints".

> A complete stranger who has nothing whatsoever to do with you, who has never tried to do anything for you, nor has been expected to, has never disappointed you. They've also never failed to disappoint you, because they have not failed in any regard whatsoever.

"never failed" != "never fails"

They said they were a follower of them though.

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