- Therefore sign
In a
mathematical proof , the "therefore" sign (Unicode|∴) is a symbol that is sometimes placed before alogical consequence , such as the conclusion of asyllogism . The symbol consists of threedot s placed in a triangle. In reading, it is pronounced "Therefore, …". It isUnicode character U+2234. While it is not generally used in formal writing, it is often used in mathematics and shorthand.History
According to Cajori, "A History of Mathematical Notations", the "therefore" sign was first used by
Johann Rahn in 1659, in the original German edition of his book "Teutsche Algebra".Related signs
The inverted form Unicode|∵, known as the "because" sign, is sometimes used as a shorthand form of "because". This is
Unicode character U+2235.The "therefore" sign is sometimes used as a substitute for an asterism [Unicode|⁂] .
To denote
logical implication orentailment , various signs are used inmathematical logic : Unicode|→, Unicode|⇒, Unicode|⊃, Unicode|⊢, Unicode|⊨. These symbols are then part of a mathematical formula, and are not considered to be punctuation. In contrast, the therefore sign is traditionally used as a punctuation mark, and does not form part of a formula.To denote a cultural or historical site (such as a ruin) on a map. Japan: National Monument [http://en.wikipedia.org/wiki/Japanese_map_symbols]
Examples
Used in a
syllogism ::All humans are mortal.:Socrates is a human.:Unicode|∴ Socrates is mortal.
In secret societies
Some secret traditions use this sign for
abbreviation instead of the usual period.This usage is much more frequent inFrench Freemasonry than in the English one."Encyclopedia of Freemasonry Part 1 and Its Kindred Sciences Comprising the ...",Albert Gallatin Mackey , page 2, reprint in 2002,Kessinger Publishing , ISBN 0766126501.]imilar symbols
*The
Āytham is a special sound of Tamil represented by Unicode|ஃ in theTamil script .ee also
*
Q.E.D. References
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