| ∴ | |
|---|---|
Therefore sign | |
| In Unicode | U+2234 ∴THEREFORE (∴, ∴, ∴) |
| Different from | |
| Different from | U+2235 ∵BECAUSE |
| Related | |
| See also | Similar signs (below) |
Inlogical argument andmathematical proof, thetherefore sign,∴, is generally used before alogical consequence, such as the conclusion of asyllogism. The symbol consists of three dots placed in an uprighttriangle and is readtherefore. While it is not generally used in formal writing, it is used inmathematics andshorthand.
According toFlorian Cajori inA History of Mathematical Notations, the Swiss mathematicianJohann Rahn used both an upright and an inverted triangle of dots to meantherefore. In the German edition ofTeutsche Algebra (1659), he used the upright triangle with its modern meaning, but in the 1668 English edition Rahn used the inverted triangle more often to mean 'therefore'.[1]: vol. 1, p. 211 Other authors in the 18th century also used three dots in a triangle shape to signify 'therefore', but as with Rahn, there was little consistency as to how the triangle was oriented. Use of an upright triangle exclusively to meantherefore (and an inverted triangle exclusively to meanbecause) appears to have originated in the 19th century. In the 20th century, the three-dot notation for 'therefore' became very rare in continental Europe, but it remains popular inAnglophone countries.[1]
Used in asyllogism:
and in mathematics:
In meteorology, the therefore sign is used to indicate "moderate rain" on astation model; the similartypographic symbolasterism (⁂, threeasterisks) indicates moderate snow.[2][3]
InFreemasonry and certain related traditions, the symbol is used to indicatea Masonic abbreviation (rather than theperiod mark used conventionally with some abbreviations). For example, "R∴W∴ John Smith" is an abbreviation for "Right Worshipful John Smith" (the termRight Worshipful is an honorific and indicates that Smith is aGrand Lodge officer).[4]
The symbol has a Unicodecode point atU+2234 ∴THEREFORE (∴, ∴, ∴). SeeUnicode input for keyboard-entering methods.
One can write the symbol inLaTeX by using theamssymb package with the\therefore command.
| ∵ ஃ ⁂ ⛬ | |
|---|---|
Similar signs | |
| In Unicode | U+2235 ∵BECAUSE (∵, ∵, ∵) U+0B83 ஃTAMIL SIGN VISARGA U+2042 ⁂ASTERISM U+26EC ⛬HISTORIC SITE |
The inverted form,∵, known as thebecause sign, is sometimes used as ashorthand form of "because".
The characterஃ (visarga) in theTamil script represents theāytam, a special sound of theTamil language.
Anasterism,⁂, is a typographic symbol consisting of threeasterisks (*) placed in atriangle. Its purpose is to "indicate minor breaks in text", to call attention to a passage, or to separate sub-chapters in a book. It is also used inmeteorology to indicate 'moderate snowfall'.
The graphically identical sign∴ serves as aJapanese map symbol on the maps of theGeographical Survey Institute of Japan, indicating a tea plantation. On some maps, a version of the sign with thicker dots,⛬, is used to signal the presence of anational monument,historic site orruins; it has its own Unicode code point.[5]
InNorwegian andDanish, a superficially similar symbol was formerly used as an explanatory symbol (forklaringstegnet). It can be typeset using theopen o followed by a colon, thus:ɔ:. It is used for the meaning "namely",id est (i.e.),videlicet (viz.) or similar.[6]
