# Tombstone (typography)

In mathematics, the **tombstone**, **halmos**, **end-of-proof**, or **Q.E.D.** symbol "∎" (or "□") is a symbol used to denote the end of a proof, in place of the traditional abbreviation "Q.E.D." for the Latin phrase "*quod erat demonstrandum*". It is inspired by the typographic practice of *end marks*, an element that marks the end of an article.^{[1]}^{[2]}

In Unicode, it is represented as character U+220E ∎ END OF PROOF. Its graphic form varies, as it may be a hollow or filled rectangle or square.

In AMS-LaTeX, the symbol is automatically appended at the end of a proof environment `\begin{proof}`

... `\end{proof}`

. It can also be obtained from the commands `\qedsymbol`

, `\qedhere`

or `\qed`

(the latter causes the symbol to be right aligned).^{[3]}

It is sometimes called a "Halmos finality symbol" or "halmos" after the mathematician Paul Halmos, who first used it in a mathematical context in 1950.^{[4]} He got the idea of using it from seeing end marks in magazines, that is, typographic signs that indicate the end of an article. In his memoir *I Want to Be a Mathematician*, he wrote the following:^{[1]}

The symbol is definitely not my invention — it appeared in popular magazines (not mathematical ones) before I adopted it, but, once again, I seem to have introduced it into mathematics. It is the symbol that sometimes looks like ▯, and is used to indicate an end, usually the end of a proof. It is most frequently called the 'tombstone', but at least one generous author referred to it as the 'halmos'.

## See also[edit]

## Notes[edit]

- ^
^{a}^{b}Paul R. Halmos,*I Want to Be a Mathematician: An Automathography*, 1985, p. 403. **^**Felici, James (2003). "The complete manual of typography : a guide to setting perfect type". Berkeley, CA : Peachpit Press.**^**"LaTeX/Theorems - Wikibooks, open books for an open world".*en.wikibooks.org*. Retrieved 2019-11-05.**^**Halmos, Paul R. (1950).*Measure theory*. New York: Van Nostrand. pp. 6. ISBN 0387900888. OCLC 529634.

## References[edit]

- Miller, Jeff (September 29, 2007),
*Earliest Uses of Symbols of Set Theory and Logic*, retrieved June 26, 2010