Turned A

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Not to be confused with Latin turned alpha.

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

Lowercase ɐ (in two story 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.

It was used in the 18th century by Edward Lhuyd and William Pryce as phonetic character for the Cornish language. In their books, both and ɐ have been used. [1] It was used in the 19th century by Charles Sanders Peirce as a logical symbol for 'un-American' ("unamerican").[2]

The symbol has the same shape as a capital turned A, sans-serif. It is used to represent universal quantification in predicate logic. When it appears in a formula together with a predicate variable, they are referred to as a universal quantifier. In traffic engineering it is used to represent flow, the number of units (vehicles) passing a point in a unit of time.

Encodings[edit]

Character ɐ
Unicode name LATIN CAPITAL LETTER TURNED A LATIN SMALL LETTER TURNED A FOR ALL
Encodings decimal hex decimal hex decimal hex
Unicode 11375 U+2C6F 592 U+0250 8704 U+2200
UTF-8 226 177 175 E2 B1 AF 201 144 C9 90 226 136 128 E2 88 80
Numeric character reference Ɐ Ɐ ɐ ɐ ∀ ∀
Named character reference ∀
Symbol font 34 22
TeX \forall

See also[edit]

References[edit]

  1. ^ Michael Everson, Proposal to add Latin letters and a Greek symbol to the UCS, ISO/IEC JTC1/SC2/WG2 N3122 L2/06-266 (2006)
  2. ^ Page 320 in Randall Dipert, "Peirce's deductive logic". In Cheryl Misak, ed. The Cambridge Companion to Peirce. 2004