Personally, my own introduction to self-reference is the most excellent The Monster at the End of This Book, a literary work which I had the great pleasure to introduce to my kids upon discovering it on the shelves of our local public library.

DO NOT TURN THE PAGE

Nice one! I remember seeing a short video, from a comment in HN, that was brilliant and was taking the idea of self-reference and our universe being a simulation to the extreme. (Spoilers follow) It was inside a big prison cell, where a new inmate arrived and there was an older man holding a box that contained a duplicate of the cell, but with real (identical) people. Someone could interact and see the results on 2 different levels/realities! Anyone remembers or knows what I’m describing?

Here you go https://www.youtube.com/watch?v=WJj_NMhYwf0

Thanks for the discovery Petros :-)

For other HN users (and future reference) the short film is titled "Room 8" by James W Griffiths [0], it won the BAFTA 2014 award for short film [1] and is based on a short script written by Oscar winning writer Geoffrey Fletcher.

[0] https://en.wikipedia.org/wiki/Room_8_(film) [1] http://awards.bafta.org/award/2014/film/british-short-film

My favorite recursive music video has to be Radiohead - Burn The Witch. Difficult to explain, but easy to intuit. Brings the listener's reality into the equation at the end, establishing a recursive link. "Model village"

Depeche Mode - Get the Balance Right! music video is an early example of computer-simulated recursive reality and really gets it right, a common trope nowadays.

My fave is the video for Björk's Bachelorette by Michel Gondry. Self-reference is one of his signature moves.

https://youtu.be/JNJv-Ebi67I

How does one do something like this https://github.com/mame/quine-relay

Does anyone know the core concept?

By nesting Quines, this is the core concept:

http://www.madore.org/~david/computers/quine.html

I have a small poem I wrote which I think is worth adding to the list.

    In haiku parse tree
        The oroborous told me
            "In haiku parse tree..."

Last line could also be "now go to first line" or "restart at line one".

Go to is thought bad

  By many who don't want to

    Go to the first line

What a nice surprise to be reading through a great list like this (finding some lovely new things I'd never heard of like 13532385396179) only to come across my own Quine tweet!

Previous HN discussion of that: https://news.ycombinator.com/item?id=25244872

I didn't know the Liar's paradox had a name :)

Decades ago (after watching this scene from Labyrinth with David Bowie : https://youtu.be/ReFhu8KYbmU ) as a teenager I wanted to make a sentence I could use in a conversation that would always self-reference wrong. First it was "I always lie." But this (less pretty) version was more "accurate" to me :

"I always tell the opposite of the truth."

"Lie" was too vague a concept : one could argue that a lie is "relative", because it depends on subjectivity = what the subject believes is the truth. The "opposite of the truth" is more "absolute" because the subject and his beliefs/knowledge are out of the equation.

I object to that specific incarnation because lying implies knowing the truth. Instead of lying, someone can just be incorrect.

This is why I ended up avoiding the concept of lying altogether. I explained this in my last paragraph :)

Once you have self-reference, these are pretty easy to create. I'm quite fond of such sentences that use no self-reference. E.g.

"is false when preceded by its quotation" is false when preceded by its quotation.

The above was, appropriately, first recorded by Willard Quine.

> "I always tell the opposite of the truth."

This is not a paradox though, is it? One can argue that you sometimes tell the opposite of the truth, and this is one of those times.

> I didn't know the Liar's paradox had a name :)

Liar's Paradox doesn't have a name.

> Liar's Paradox doesn't have a name.

"Liar's paradox" is the "name" I discovered in this list today, to describe this kind of paradox. It has a wikipedia page, and pages in other encyclopaedias under this title. So I guess this is the most recognized name for it.

And now for something completely different: does the Liar's paradox name has a name? We know, due to the White Knight via Lewis Carroll, that e.g. the name of the song "A-sitting On A Gate" is actually "The Aged Aged Man" — are there other examples of such curious nomenclature?

Sorry, that was a tongue-in-cheek comment, to create another paradox. I should have been more clear.

Well, I used the word "always" to make sure noone can argue I sometimes tell the truth. I am not sure I understand your point.

Yes, but using "always" makes it a non-paradox. If you are someone who sometimes tells the truth you might have also said this sentence, which would make it (the sentence) simply "not true" instead of a paradox.

To disprove an universal quantification you need just a counter example of one instance, hence you are introducing an easy weakness

I was surprised to not see Droste cocoa in there.

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

The best example of this that I can think of is sharing your screen while showing your screen sharing app window.

…or simply connecting via screen sharing to your own screen.

I like that the opening of "YYZ" by Rush features Neil Peart tapping out those letters in Morse Code => https://www.songfacts.com/facts/rush/yyz

I've seen a couple of insurances recently of people who put up a photo of an index page of a textbook. In each case it was from a CS book, and the index of the word "recursion" has its own page number in it.

Back in the early days of Reddit someone made digg and reddit posts that linked to each other. Can't find those now. I'm pretty sure the old/original digg content doesn't exist anymore.

HN post that upvoted itself: https://news.ycombinator.com/edit?id=3742902 (from 2012, before HN put CSRF protection in place).

There must be a self-linking post as well, but I can't find it

someone did this for a tweet as well...

"The Most Beautiful Program Ever Written" should be in this list.

https://youtu.be/OyfBQmvr2Hc?t=3383

Believe it or not, I was at that PWL meetup in 2017! LISP and metacircular evaluation were definitely among the things that inspired the list. The "Micro-Manual for LISP" mentioned in the talk is on it.

A couple more I thought of

- “We Are In A Book” (Gerald & Piggie book) - characters refer to themselves being in that book

- Godel, Escher, Bach (Douglas Hofstadter) - pretty much entirely about self-referential structures

I’m happy to see that the repo lists itself as one of the examples…

Love that the website lists itself. I snorted my coffee.

Oh c'mon, it doesn't even link to itself. ;)

https://github.com/aztek/awesome-self-reference/blame/master... was from 3 years ago

Like this? https://news.ycombinator.com/item?id=29891928

Here you go:

https://news.ycombinator.com/item?id=29401449

Here is the silly title I forged for myself: unique first utterer of this impredicative performative statement.

Of course, both notions deserve credits:

- impredicativity was coined by Bertrand Arthur William Russell

- performativity was identified by John Langshaw Austin

Is "recursion" analogous to self-reference in computing?

pretty much, as is a circular dependency in OOP or dependency management.

Apparently, "contents" line is missing in the contents.

Love it how it has a link to itself in Web examples section.

This comment is a lie.

The parent comment is not a lie.

The two above comments are as true as each other.