In predicate logic, an existential quantification is the predication of a property or relation to at least one member of the domain. It is denoted by the logical operator symbol ∃ (pronounced "there exists" or "for some"), which is called the existential quantifier. Existential quantification is distinct from universal quantification ("for all"), which asserts that the property or relation holds for any members of the domain.

Symbols are encoded U+2203 ∃ there exists (HTML: ∃ ∃ as a mathematical symbol) and U+2204 ∄ there does not exist (HTML: ∄).

Consider a formula that states that some natural number multiplied by itself is 25.

0·0 = 25, or 1·1 = 25, or 2·2 = 25, or 3·3 = 25, and so on.

This would seem to be a logical disjunction because of the repeated use of "or". However, the "and so on" makes this impossible to integrate and to interpret as a disjunction in formal logic. Instead, the statement could be rephrased more formally as

For some natural number n, n·n = 25.

This is a single statement using existential quantification.

Glenn Greenwald (born March 6, 1967) is an American lawyer, columnist, blogger, and author. Greenwald worked as a constitutional and civil rights litigator before becoming a contributor (columnist and blogger) to Salon.com, where he focuses on political and legal topics. He has also contributed to other newspapers and political news magazines, including The New York Times,The Los Angeles Times,The Guardian,The American Conservative,The National Interest, and In These Times.

Greenwald has written four books, three of which have been New York Times bestsellers: How Would a Patriot Act? (2006); A Tragic Legacy (2007), and With Liberty and Justice for Some: How the Law Is Used to Destroy Equality and Protect the Powerful, released in October 2011. He also wrote Great American Hypocrites (2008).

In March 2009, he was selected, along with Amy Goodman of Democracy Now!, as the recipient of the first annual Izzy Award by the Park Center for Independent Media, an award named after independent journalist I.F. "Izzy" Stone and devoted to rewarding excellence in independent journalism. The selection panel cited Greenwald's "pathbreaking journalistic courage and persistence in confronting conventional wisdom, official deception and controversial issues."

Benedict Timothy Carlton Cumberbatch (born 19 July 1976) is an English film, television, radio and theatre actor. His most acclaimed roles include Stephen Hawking in the BBC drama Hawking (2004); William Pitt in the historical film Amazing Grace (2006); the protagonist Stephen Ezard in the miniseries thriller The Last Enemy (2008); Paul Marshall in Atonement (2007); Bernard in Small Island (2009); Sherlock Holmes in the modern BBC adaptation series Sherlock (2010); and Peter Guillam in the spy thriller Tinker Tailor Soldier Spy (2011).

In February 2011, he began playing both Victor Frankenstein and his creature opposite Jonny Lee Miller in Danny Boyle's stage adaptation of Mary Shelley's Frankenstein. The play had a three-month run at the National Theatre. In late 2011, he played Major Stewart in Steven Spielberg's War Horse (2011). The film received five BAFTA nominations and six Academy Award nominations, including the Best Picture nomination in 2012. He also played Peter Guillam, one of the pivotal roles in Tomas Alfredson's Tinker, Tailor, Soldier, Spy (2011), which was nominated for three Academy Awards and 11 BAFTA Awards. Tinker Tailor Soldier Spy was also nominated for Best Picture in 2012.

Francis Albert "Frank" Sinatra,  /sɨˈnɑːtrə/, (December 12, 1915 – May 14, 1998) was an American singer and film actor.

Beginning his musical career in the swing era with Harry James and Tommy Dorsey, Sinatra became an unprecedentedly successful solo artist in the early to mid-1940s, after being signed to Columbia Records in 1943. Being the idol of the "bobby soxers", he released his first album, The Voice of Frank Sinatra in 1946. His professional career had stalled by the 1950s, but it was reborn in 1953 after he won the Academy Award for Best Supporting Actor for his performance in From Here to Eternity.

He signed with Capitol Records in 1953 and released several critically lauded albums (such as In the Wee Small Hours, Songs for Swingin' Lovers, Come Fly with Me, Only the Lonely and Nice 'n' Easy). Sinatra left Capitol to found his own record label, Reprise Records in 1961 (finding success with albums such as Ring-a-Ding-Ding!, Sinatra at the Sands and Francis Albert Sinatra & Antonio Carlos Jobim), toured internationally, was a founding member of the Rat Pack and fraternized with celebrities and statesmen, including John F. Kennedy. Sinatra turned 50 in 1965, recorded the retrospective September of My Years, starred in the Emmy-winning television special Frank Sinatra: A Man and His Music, and scored hits with "Strangers in the Night" and "My Way".

Stefon Harris (born March 23, 1973) is an American jazz vibraphonist. In 1999, the Los Angeles Times called him "one of the most important young artists in jazz" who is "at the forefront of new New York music" and "much in demand as a star sideman". Harris has played with several jazz luminaries including Kenny Barron, Steve Turre, Kurt Elling, and Charlie Hunter, in addition to releasing several of his own critically well-regarded albums.

Harris is a resident of Newark, New Jersey.

A 1991 graduate of Albany High School, Harris earned his bachelor's (in 1995) and master's (in 1997) from Manhattan School of Music in New York City. He credited his teachers in High School, saying they recognized his "passion for music early on and offered lessons and the chance to bring home instruments to practice." He has stated that "Music education and performance in ensembles, like the Empire State Youth Orchestra, exposed me to me to other cultures and genres." He also was the captain of the high school wrestling team. Of Manhattan School of Music he has said: "The School gave me the opportunity to explore the diversity of both classical and jazz music and find the direction I wanted to go artistically."