A curated list of examples of self-reference in art, science, and technology.
- The Treachery of Images – A painting by René Magritte.
- Triple Self-Portrait – A painting by Norman Rockwell.
- Mise en abyme – A formal technique of placing a copy of an image within itself.
- Droste effect – The effect of a picture recursively appearing within itself, in a place where a similar picture would realistically be expected to appear.
- Autogram – A sentence that describes itself in the sense of providing an inventory of its own characters.
- Fumblerule – A rule of language or linguistic style, humorously written in such a way that it breaks this rule.
- Recursive acronym – An acronym that refers to itself.
- Liar’s paradox – This sentence is false.
- Russell’s paradox – Does the set of all those sets that do not contain themselves contain itself?
- Trott’s constant – The unique number whose digits equal its continued fraction coefficients.
- 13532385396179 – A number that is its own prime factorization, that is 13532385396179 = 13 × 53² × 3853 × 96179.
- Tupper’s self-referential formula – A formula that visually represents itself when graphed at a specific location in the (x, y) plane.
- Life in Life – Conway’s Game of Life running inside Conway’s Game of Life using OTCA metapixels.
- Quine – A computer program that takes no input and produces a copy of its own source code as its only output.
- An Ouroboros Quine – A Ruby program that generates Rust program that generates Scala program that generates (through 128 languages in total) REXX program that generates the original Ruby code again.
- A radiation hardened quine – A Ruby quine that remains a quine after any one of the characters in its source code is removed.
- quinesnake – A quine that plays snake over its own source.
- The Qlobe – A Ruby quine with an ASCII image of a globe in its source code that rotates by 45 degrees after each run, eventually coming around after eight runs.
- html_wysiwyg – A truly naked, brutalist html quine.
- Meta-circular evaluator – An interpreter that defines each feature of the interpreted language using a similar facility of the interpreter’s host language.
- A Micro-Manual for LISP – Not the whole truth – The LISP interpreter written in LISP.
- Fix-point combinator – A higher-order function fix that, for any function f that has an attractive fixed point, returns a fixed point x of that function.
- Universal Turing machine – A Turing machine that can simulate an arbitrary Turing machine on arbitrary input.
- Bootstrapping – A technique for producing a self-compiling compiler – that is, compiler (or assembler) written in the source programming language that it intends to compile.
- Man man – Manual pager man page (accessed using
$ man man).
- Wikipedia – An article about Wikipedia on Wikipedia.
- Wayback Machine – Snapshots of The Internet Archive stored in The Internet Archive.
- Quine Tweet – A tweet that quote tweets itself.
- Awesome Self-Reference – A curated list of examples of self-reference in art, science, and technology, which includes itself.
- Hofstadter’s law – “It always takes longer than you expect, even when you take into account Hofstadter’s Law”.
- Miniatur Wunderland – The world’s largest model railway in Hamburg, Germany has a model of itself in its model of Hamburg.
- Untitled Goose Game – The village where Untitled Goose Game takes place contains a small model version of itself, and also a tiny version of the model inside that.