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Re:Endless Horse by ketanmaheshwari on Thursday December 29, 2022 @08:19PM (#34180464)
What does this mean? Could someone please clarify what this prose / poem means or what is the author's intention? Going completely over my head.
Re:Endless Horse by michaelnoguera on Thursday December 29, 2022 @08:43PM (#34180696)
The author has devised a logical argument based off drawing equivalences between similar sounding words ("forelegs" vs "four legs"). The absurdity of the conclusion that a horse has infinite legs and the novelty of the invalid leaps in reasoning makes the story humorous.
Re:Endless Horse by jdkee on Thursday December 29, 2022 @08:47PM (#34180736)
A mare has four (4) legs.

But no mare, meaning there is not any mare such that it has five (5) legs.

Thus the cardinality of "no mare" > the cardinality of "mare".

Re:Endless Horse by akiselev on Thursday December 29, 2022 @08:48PM (#34180744)
It's a series of misspellings, puns, and tortured logic.

> It has two hind legs, aside from its fourlegs.

Hind legs are the opposite of forelegs so the statement is true but misspelled, and [---tortured logic here---] two hind legs plus "four" forelegs totals to six legs.

> Which means it has six legs... Now six is an even number, so it must have an even number of legs... But six is an odd number of legs for a horse to have, so it has an odd number of legs.

Six is an even number but it's "odd" - as in strange - for a horse to have six legs so horses [---tortured logic here---] must also have an odd - as in mathematical - number of legs.

> The only number that is both odd an even is infinity. Since a horse has both an odd an even number of legs, it must have infinite legs.

Infinity is a complicated "number" with different interpretations and [---tortured pure math here---] if you stretch some of them to the breaking point, the only horse that can have both an "even" and an "odd" number of legs is one that "must have infinite legs"

> But there is one horse, that not only has an infinite number of legs, it has legs that are infinitely long.

This plays on the ambiguity of "infinite legs" which could mean an "infinite number of legs" or "infinitely long legs".

All in all, thumbs up. Cost me some cherry switches thanks to projectile tea.

Re:Endless Horse by thaumasiotes on Friday December 30, 2022 @12:42AM (#34182204)
> Infinity is a complicated "number" with different interpretations and [---tortured pure math here---] if you stretch some of them to the breaking point, the only horse that can have both an "even" and an "odd" number of legs is one that "must have infinite legs"

I am not aware of this math; can you elaborate? In pretty much any system, there is no number that is both even and odd, and including infinite quantities in the system doesn't change that.

Re:Endless Horse by naet on Friday December 30, 2022 @02:11AM (#34182686)
Infinity is an infinitely high number. What is Infinity plus one? It must still be Infinity, since it's already infinitely high and can't go any higher.

But if you have an odd number and add one, you get an even number (and vice versa). For Infinity = Infinity + 1 to hold true, Infinity must be both odd and even.

Or something like that. It's probably more accurate to say Infinity is neither odd nor even. If you add 2+2+2+2... up to infinity, it might appear even. But that could also be equivalent to 1+3+1+3+1... to infinity, which would be alternating even and odd. Or 1+2+2+2+2... which would always be odd.

Infinite quantities bend or break a lot of typical rules that other rational numbers follow.

Re:Endless Horse by Swizec on Friday December 30, 2022 @03:07AM (#34183000)
If I remember my college set theory correctly, this is because there are infinite infinities.

2+2+2+… is a different infinity than 2+1+2+1+…

You can construct infinite sets of numbers that do not overlap. Odd vs. Even infinity is the example our professor used in class to show the concept. I don’t remember enough to replicate here.

Re:Endless Horse by greggertt on Friday December 30, 2022 @03:56AM (#34183271)
Wow way to kill the enjoyment of a nonsense verse
Re:Endless Horse by Swizec on Friday December 30, 2022 @06:00AM (#34183916)
Nah the verse was wonderful, I thoroughly enjoyed it.
Re:Endless Horse by thaumasiotes on Friday December 30, 2022 @06:28AM (#34184078)
In the ordinal-numbers model that your notation leans toward, 2+2+2+... and 2+1+2+1+... are definitely the same infinity, both ω.

On the other hand, you reminded me that conditionally convergent series may converge to different sums depending on how you choose to group their terms, which is fun. (That is, [(s_1 + s_2) + s_3 + (s_4 + s_5) + s_6 + ...] may have a different sum than [(s_1 + s_2) + (s_3 + s_4) + (s_5 + s_6) + ...] does.)†

† I hope this is true; I can't find a cite for it. The more famous theorem is that you can get any sum you want by reordering the terms, but I think regrouping is good enough to get you different sums, if not arbitrary sums.

Re:Endless Horse by thaumasiotes on Friday December 30, 2022 @06:55AM (#34184232)
> What is Infinity plus one? It must still be Infinity, since it's already infinitely high and can't go any higher.

This is a mistake. That is how the extended reals behave. There are other systems. The diagonalization argument will already tell you that if you're at infinity, you can still go higher. This is also true for ordinal numbers and nonstandard analysis. It is the general case; the behavior in the extended reals is a special case.

> But if you have an odd number and add one, you get an even number (and vice versa). For Infinity = Infinity + 1 to hold true, Infinity must be both odd and even.

This is much worse; your conclusion is unrelated to your premise. You would need an additional premise, that infinity is either even or odd, which you didn't bother to supply. The same argument will tell you that either (a) 1.3 is even and 2.3 is odd, or (b) 1.3 is odd and 2.3 is even. (a) and (b) are both false.

Re:Endless Horse by lozenge on Friday December 30, 2022 @04:10AM (#34183331)
A set is even if you can pair each element up with another element.

A set is odd if you can pair each element with another element and have one element left over unpaired.

Then infinity is even and odd.