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   Self-referentiality can be quirky, interesting, and sometimes rather simple, like for example this sentence.
If used excessively however, it can become a little irksome, so I'll stop now.

Here is a 'story' which might be considered a prime example of that irksomeness I mentioned. I like the very end especially, although it cannot be taken in isolation.

In an act of daring self-referential civil disobedience, I took this photo:

If it weren't for the fact that it tells the time, the only information provided by this device would be the fact that it provides information:

Examples of self-referentiality:
   (If you can't understand why any example is self-referential, highlight the white text which follows it) (like this)

First - this is the first example
Imagine a world with no hypothetical situations. This is a hypothetical situation. This does not offer any further clues.
This sentence has cabbage six words - if it didn't have the word 'cabbage' then it wouldn't have cabbage six words (G.E.B)
new! There are no redundant redundant words in this sentence. This one just boggles my mind, and I came up with it! Note that the first redundant can be interpreted as a qualifier.
This statement is false clearly refers to itself. Whether it is true or not is another matter entirely.
This statement is not provable by me. (Useful illustration of Godel's incompleteness theorem) see above
The smallest number that cannot be stated in fewer than 22 syllables - a puzzle - what number is being referred to?
Consider the set of all sets that have not yet been considered. That set is self-referential, since it contains itself... until it is considered.
Mispeltt - 'Mispelt' has been mispelt.
Ptyo - a typo has evidently been made while typing the word 'typo'.
Repetition - not self-referential at all. Why is it here?
sdrawkcaB - backwards backwards.
The 'pre' in prefix is itself a prefix
Quinquesyllabic - the word that means 'having five syllables' has five syllables.
Self-referential - If 'self-referential' is self-referential, then it is clearly self-referential. But if it isn't, then it isn't. Clearly.
Word is a word.
Ineffable - a. beyond description, too great for words - ineffably adv. -ability n.
Recherche - [adj] lavishly elegant and refined. Somewhat like the word itself. Arguable.
Sesquipedalian (a.) Measuring or containing a foot and a half; as, a sesquipedalian pygmy; - sometimes humorously applied to long words. [www.brainydictionary.com].
Non-phonetic is not spelt phonetically.
Illiterate illiteration - only an alliteration because it is written by me, an illiterate person.
new! "All clichés should be avoided like the plague" (attributed to Arthur Christiansen, found in "The Joy of Clichés" by Nigel Rees) It's a cliché, innit
This is not the last example on the list. Indeed, it is not. But it does refer to itself.
Inelegantness - an inelegant word, appropriately enough.
Pseudo-Greek is only so because the word 'pseudo' is Greek, but 'Greek' itself isn't.
Aibohphobia (credited to Imre Leader, although the Wikipedia cites the Wizard of Id) - meaning, the fear of palindromes.
Grammar message in Microsoft Word: "This may not be a complete sentence" Probably not actually referring to itself, really.
TLA - Three Letter Abbreviation - or Acronym, depending on which side of that fence you sit on...
Abbr. - the abbreviation for 'abbreviation'.
This sentence contains three a's, three c's, two d's, twenty seven e's, four f's, two g's, ten h's, eight i's, thirteen n's, six o's, ten r's, twenty five s's, twenty three t's, three u's, three v's, six w's, three x's, and four y's. (Too many more like that can be found here.) Check the numbers if you don't believe them! One of the more interesting examples that begins with 'This sentence...".
In order to understand the theory of recursion, one must first understand the theory of recursion. How recursive!
I don't speak English (Je ne parle pas Francais, etc...) Speaking about speaking a language, in that language...
Arial - this is the font called Arial. This example is actually used by some programs to illustrate your choice of fonts.
Stretching a metaphor to breaking point, then snapping it, shredding it into small pieces and mashing them into a pulp. 'To stretch a metaphor' is an oft-used metaphor. This one does to itself exactly what it says, metaphorically speaking.
Adjectival is itself an adjective.
Illegitimate - there is nothing self-referential about this word, hence it is illegitimate for entry on this list. Hence it isn't.
There are 3 kinds of people in the world; those that can count, and those that can't. (The author belonging to the latter.)
Actually, there are 10 kinds of people in the world; those that can count in binary, and those that can't. (The author being the former in this case.)
"a7H.4hwJ?22i" is an example of a good password. Sadly, because people are now aware of that fact, it is no longer true.
Repetition - This non self-referential word has now appeared twice on the list... thereby justifying its inclusion.
A rag man - this one is very nice, you should try to work it out! The answer is at the bottom of the page.
Penultimate - the penultimate word on the list.
This is the last example on the list. Yes, it is.

Self-referential quotes:
   I collect interesting things I hear people say, and some of those are collected here. Here are some self-referential examples:

Tim (yes, me): "People only hear what they expect to monkey." Actually, people only hear what they expect to hear.

Phil: "How do you spell 'Johnny'?"
Paula: "J for John..."

Me: Originality is undeteced plagiarism.

Poem, Verse and Song of the self-referential kind:
   It seems there are quite a number of possible entries for this category, so as I encounter them I shall add them here.
First, a limerick, origin unknown:
(Actually, it's arguable whether it is a limerick or not, but it's still self-referential).
There once was a man from the sticks,
who liked to write limericks,
but he failed at the sport
because he wrote them too short.
(I think he just did it for kicks)
   From Eureka 49 (1992) [precise reference to be confirmed], we have the following Haiku by Anton G. Cox:

   The table provides each letter with its numerical position in the alphabet. The lines total 166, 239 and 170 respectively, and these sum to 575.

updated!   'Da Vinci's notebook' produced the delightful track 'Title of the Song' You can download the mp3 here, and read the lyrics here.

Dictionary definitions that include themselves:
or, as...
[There must be more. Find them and tell me, at ranma-tim@care2.com !]

Redundancy in Acronyms:
   Often an acronym contains within it a word so important that people say that word as well as the acronym that contains it. This is sort of self-referential, and here are some common examples:
AC current (Alternating Current current)
ISA account (Individual Savings Account account)
ISIC card (International Student Identity Card card) (as endorsed by the address of their own website!)
PAT testing (Portable Appliance Testing testing)
PIN number (Personal Identification Number number)
SI system (Système Internationale system, i.e. International System system)

(Further suggestions may be sent to the usual address...)


Puzzles:
· Here is Jim Propp's "Self-Referential Aptitude Test".
· Here is one based on Base 3 self-referential algebra.
· Is the answer to this question no?
· Fill in the blank: "In this sentence there are ____ letter Es - I know this because I counted them myself". (Adapted from Cliff Pickover's daily puzzle calender, 21st May, 2004)
· (Adam's "What is the value of x?" will one day be linked to here, if and when I can find it.)
· Which of the objects in the following picture is the odd one out?
Ok, maybe it isn't self-referential, but it feels similar anyway.
· Pentominoes can be used to make pentominoes, which is a bit self-referential. The meta-pentominoes can then be assembled into a rectangle. The pentominoes can then be coloured using four differenct colours such that no pieces of the same colour are adjacent. Finally, you can treat the resulting image as a maze: only using two colours, try to make it from the left to the right. (Diagonal moves not allowed):

start

finish

More self-referentiality:
   A rather amusing article here has some self-referentiality in it.
New!   In a similar vein, here's an excellent piece by Steve Martin.
   If you can't get enough self-referential stuff, then you should read "Godel, Escher, Bach" by Douglas R. Hofstadter.
He is truly obsessed with it.

Thanks to Michael Greene, Tarim, and Laurence O'Toole for their contributions to and suggestions for this page, including this sentence of thanks.

Link to Main Page > Link to Puzzles > Link to the self-referential page
"A rag man" is an anagram of 'anagram'.