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There Is(Ǝ) – Such That (∋)

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Re: There Is(Ǝ) – Such That (∋)

#21

Post by frank_nitti »

bayesnet wrote: post #8

I don’t think I have ever seen ∋ used to mean “such that” so I was very confused until I got to the explanation (as it were; why CONTAINS AS MEMBER is being used to mean “such that” is never explained).

Interesting, my experience in classes using set theory was the opposite, where ∋ only meant “such that” and ∈ only meant “is a member of”.

Learning programming syntax at the same time made it frustrating to learn that math symbols were less strictly defined and less universal, that it was best to write proofs/derivations/etc in plain English in many cases instead of the neat symbols

Re: There Is(Ǝ) – Such That (∋)

#22

Post by brookst »

lloeki wrote: post #15
dist-epoch wrote: post #2

The kind of exploration that would require a massive one-month of full-time investment before LLMs. Now doable in days. (I don't know on which side of this author was)

I've seen such explorations done over a couple of days during weekend hackathons or gamejams. Have we gotten so addicted to our daily token fix that we can't even fathom focusing for 48h?

Not me, but I would produce a much larger output with 48h focus on my token fix.

Re: There Is(Ǝ) – Such That (∋)

#23

Post by ameliaquining »

npinsker wrote: post #7

For me at least, the post is kinda confusing and feels a bit overwrought (“there exists a raven such that the vector of hours”?), and was hard to understand at first. Sadly, in the wonderful year of 2026, I can’t help myself wondering if it was all written by an LLM, prompted by “be mysterious” or similar — though I still wouldn’t bet on it. The project is cool! It’s a simple visual graph layout system for making you…

Pangram says human-written. It does have some stylistic quirks often associated with LLMs, but those aren't a reliable indicator.

Re: There Is(Ǝ) – Such That (∋)

#25

Post by dabraham1248 »

bayesnet wrote: post #8

I don’t think I have ever seen ∋ used to mean “such that” so I was very confused until I got to the explanation (as it were; why CONTAINS AS MEMBER is being used to mean “such that” is never explained).

Same. I recalled pipe being used for "such that". But [per wikipedia](https://en.wikipedia.org/wiki/Glossary_of_mathematical_symbo...), that's specifically "set-builder notation", and the _last one_ of the twelve instances of the string "such that" on the page (though I don't know if they're ordered by usage, "alphabetically", or what).

Re: There Is(Ǝ) – Such That (∋)

#26

Post by MarkusQ »

bayesnet wrote: post #8

I don’t think I have ever seen ∋ used to mean “such that” so I was very confused until I got to the explanation (as it were; why CONTAINS AS MEMBER is being used to mean “such that” is never explained).

This isn't quite what's going on. A better reading might be "which is a";

"Ǝx s.t. x∈ℕ" (there exists an x such that x is in the naturals) is just being shortened to "Ǝx∋ℕ" (there exists an x in the naturals), or there exists an x which is in the naturals.

It's not really that different from the normal usage.

Re: There Is(Ǝ) – Such That (∋)

#27

Post by stackghost »

npinsker wrote: post #7

For me at least, the post is kinda confusing and feels a bit overwrought (“there exists a raven such that the vector of hours”?), and was hard to understand at first. Sadly, in the wonderful year of 2026, I can’t help myself wondering if it was all written by an LLM, prompted by “be mysterious” or similar — though I still wouldn’t bet on it. The project is cool! It’s a simple visual graph layout system for making you…

Whichever field of study these backwards E symbols are from, I've never taken a course in it.

So for me it's "Backwards E a raven Italics Backwards E the vector of hours" and I closed the tab there.

After reading this comment the symbols are now clear but by that point I'd already lost interest and moved on with my life.

Maybe this is only for people who already know set theory or whatever the backwards E comes from, and that's fine, I guess, but it was pretty annoying not to have any explanation whatsoever at the top.

I only learned that this is something to do with clocks from the comments.

Re: There Is(Ǝ) – Such That (∋)

#28

Post by drdeca »

MarkusQ wrote: post #26
bayesnet wrote: post #8

I don’t think I have ever seen ∋ used to mean “such that” so I was very confused until I got to the explanation (as it were; why CONTAINS AS MEMBER is being used to mean “such that” is never explained).

This isn't quite what's going on. A better reading might be "which is a"; "Ǝx s.t. x∈ℕ" (there exists an x such that x is in the naturals) is just being shortened to "Ǝx∋ℕ" (there exists an x in the naturals), or there exists an x which is in the naturals. It's not really that different from the normal usage.

If that’s it, why is it using ∋ rather than ∈? I would expect “Ǝx∈ℕ”.

Re: There Is(Ǝ) – Such That (∋)

#29

Post by pwdisswordfishq »

MarkusQ wrote: post #26
bayesnet wrote: post #8

I don’t think I have ever seen ∋ used to mean “such that” so I was very confused until I got to the explanation (as it were; why CONTAINS AS MEMBER is being used to mean “such that” is never explained).

This isn't quite what's going on. A better reading might be "which is a"; "Ǝx s.t. x∈ℕ" (there exists an x such that x is in the naturals) is just being shortened to "Ǝx∋ℕ" (there exists an x in the naturals), or there exists an x which is in the naturals. It's not really that different from the normal usage.

> Ǝx∋ℕ

"There is an x such that the set of natural numbers is a member of x"?

Re: There Is(Ǝ) – Such That (∋)

#30

Post by tel »

PufPufPuf wrote: post #3

I keep hearing about the "Recurse center". I tried to understand from their website what exactly is it, but only thing I got was "a sabbatical where you work on random stuff and talk with people doing the same" which still doesn't really click. But clearly it leads to cool stuff like this.

I think you've got it. You go in each day and work on things and talk with people working on things. There are multiple opportunities to share weekly, one or two are pretty regular and the rest are self-organized. Maybe you learn about something new and dive in, maybe you come up with a project and share it with others.

I think the beating heart is that everyone is there with some passion to learn and build and you're encouraged to do so collaboratively. It's surprising, I feel, how rare it is to have a community of folks who are all learning together and not afraid to dive in and figure things out. Recurse Center is a chance to spend 6 or 12 weeks building and then living in a place like that.

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