"Elementary, my dear Watson" - Sherlock Holmes
This phrase was never uttered by the character in any of Sir Arthur Conan Doyle's written works. Though "Elementary," and "...my dear Watson." both do appear near the beginning of The Crooked Man (1893), it is the "...my dear Watson" that appears first, and "Elementary" is the succinct reply to Watson's exclamation a few lines of dialogue later. This is the closest these four immortal words ever appear together in the canon.
The association of this quote with the Sherlock Holmes character likely comes from the closing lines of the 1929 film The Return of Sherlock Holmes.
"The end justifies the means" - Machiavelli
Attributed to the political theorist Niccolo Machiavelli's work The Prince. The line is actually from a book in which a fictional Machiavelli is a character.
"Play it again, Sam" - Ingrid Bergman (Casablanca)
Actual quote: "Play it Sam, for old times' sake, play 'As Time Goes By'."
"My momma always said life was like a box of chocolates. You never know what you're gonna get." - Forrest Gump
This famous line is spoken by Tom Hanks, playing Forrest Gump in the 1994 film of the same name. However, in Winston Groom's original novel, the "box of chocolates" line is rather different: "Bein' an idiot ain't no box of chocolates." Groom reportedly dislikes the change.
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