Turned A

{{Short description|Letter of the Latin Alphabet and an IPA sample}}

{{confusion|Latin turned alpha}}

{{redirect|ɐ|the sound this letter represents in IPA|Near-open central vowel}}thumb

Turned A (capital: , lowercase: ɐ, math symbol ) is a letter and symbol based upon the letter A.

Modern usage

  • Lowercase ɐ (in Roman, or "two-storey" form) is used in the International Phonetic Alphabet to identify the near-open central vowel. This is not to be confused with the turned alpha or turned script a, ɒ, which is used in the IPA for the open back rounded vowel.{{cite book|title=Handbook of Standards and Resources for Spoken Language Systems|first1=Dafydd|last1=Gibbon|first2=Roger Moore|last2=Richard Winski|publisher=Walter de Gruyter|year=1997|isbn=9783110153668|contribution=Table A.19: IPA Table (ordered by number) (continued)|page=679|contribution-url=https://books.google.com/books?id=0ElXJGBO79YC&pg=PA679}}
  • The logical symbol has the same shape as a sans-serif capital turned A. It is used to represent universal quantification in predicate logic, where it is typically read as "for all". It was first used in this way by Gerhard Gentzen in 1935, by analogy with Giuseppe Peano's turned E notation for existential quantification and the later use of Peano's notation by Bertrand Russell.{{cite web |last=Miller |first=Jeff |title=Earliest Uses of Symbols of Set Theory and Logic |url=http://jeff560.tripod.com/set.html |work=Earliest Uses of Various Mathematical Symbols}}

Historical usage

File:Turned A in Edward Lhuyd, Archaeologia Britannica, 1707, p. 226.png | Turned a presented in Edward Lhuyd's Archaeologia Britannica, 1707.

File:Turned A in William Pryce, Archaeologia Cornu-Britannica, 1790, p. 1.png | Turned a in William Pryce's Archaeologia Cornu-Britannica, 1790.

Because of the relative ease of creating this letterform using traditional printing methods, it had frequent and varied historical uses. According to the principle of acrophony, the letter A originated from the Proto-Sinaitic alphabet as a symbol representing the head of an ox or cow (aleph), its orientation and original meaning having been lost over time. The turned A symbol restores the letter to a more easily recognizable logographic representation of an ox's head.{{cite book |last= Jensen |first= Hans|author-link= |date= 1969|title= Sign, Symbol, and Script|publisher= G.P. Putman's Sons|location= New York|page= 262|isbn=9780044000211}}

A denarius coin from the Roman Republic has been found, struck with a (capital) turned A, in the collection of a Madrid-based numismatist; it is unclear whether this was intentional, or a printer's error for a V.{{cite journal|title=Some unlisted varieties and rare dies in Roman Republican denarii|first=Pierluigi|last=Debernardi|journal=The Numismatic Chronicle|volume=170|year=2010|pages=93–97|jstor=42678886}}

It was used in the 18th century by Edward Lhuyd and William Pryce as a phonetic character for the Cornish language. In their books, both and ɐ have been used.Michael Everson, Proposal to add Latin letters and a Greek symbol to the UCS, [http://std.dkuug.dk/jtc1/sc2/wg2/docs/n3122.pdf ISO/IEC JTC1/SC2/WG2 N3122 L2/06-266] (2006) It was used in the 19th century by Charles Sanders Peirce as a logical symbol for un-American.Page 320 in Randall Dipert, "[https://books.google.com/books?id=3suPBY5qh-cC&q=unAmerican&pg=PR7 Peirce's deductive logic]". In Cheryl Misak, ed. The Cambridge Companion to Peirce. 2004

{{Unichar|1D44|MODIFIER LETTER SMALL TURNED A}} is used in the Uralic Phonetic Alphabet,{{Cite web|url=https://www.unicode.org/L2/L2002/02141-n2419-uralic-phonetic.pdf|title=L2/02-141: Uralic Phonetic Alphabet characters for the UCS|date=2002-03-20|first1=Michael|last1=Everson|authorlink1=Michael Everson|display-authors=etal}} a system developed in the early 20th century for transcribing Uralic languages. However, as this system was not standardized across (nor within) languages, it has been supplanted in this use by the International Phonetic Alphabet.{{cite conference

| last1 = Simon | first1 = Eszter

| last2 = Mus | first2 = Nikolett

| editor1-last = Tyers | editor1-first = Francis M.

| editor2-last = Rießler | editor2-first = Michael

| editor3-last = Pirinen | editor3-first = Tommi A.

| editor4-last = Trosterud | editor4-first = Trond

| contribution = Languages under the influence: Building a database of Uralic languages

| contribution-url = https://aclanthology.org/W17-0603

| date = January 2017

| doi = 10.18653/v1/W17-0603

| location = St. Petersburg, Russia

| pages = 10–24

| publisher = Association for Computational Linguistics

| title = Proceedings of the Third Workshop on Computational Linguistics for Uralic Languages| url = http://real.mtak.hu/72455/1/W17_0603_u.pdf

}}

Encodings

{{charmap

| 2C6F | name1 = LATIN CAPITAL LETTER TURNED A

| 0250 | name2 = LATIN SMALL LETTER TURNED A

| 2200 | name3 = For All

| map1 = Symbol font | map1char3 = 22

| namedref1 = TeX | ref1char3 = \forall

}}

See also

References

{{reflist}}

{{Latin script|a}}

{{Common logical symbols}}

Category:Logic symbols

A

Category:Phonetic transcription symbols