Hacker News Reader

Yes, because a proposition without it is a statement about a thing: "I exist." Whereas, with not in it is a statement about everything that exists: "Black swans do not exist." You need knowledge of one thing in the former, you need knowledge of everything in the latter.

It's not just the word "not" it's an odd number of nots (double negatives and all that).

View on HN

"Black swans do not exist" isn't wholly a statement about everything that exists. It's a statement about the possibility of the property of "being a black swan" to exist.

It is a statement about an abstraction, not existence. Like saying "the cup is above the table" is a statement about the existence of the "above-ness with respect to the table" of the cup. One needn't survey all of reality to know if it is possible for some abstraction to exist. It need only be consistent with the rest of your language, so that's all you need to survey.

I would describe what you're talking about as "black swans cannot exist". That is an even stronger statement, because it also implies that black swans do not currently exist.

Reply on news.ycombinator.com