(i believe it originated from the TV show how i met your mother)
Although the provenance of the rule is unclear, it is sometimes said to have originated in France.[81] The rule appears in John Fox Jr.'s 1903 novel The Little Shepherd of Kingdom Come,[84] in American newspapers in 1931 attributed to Maurice Chevalier,[85] and in The Autobiography of Malcolm X, attributed to Elijah Muhammad.[86]
In many early sources, the rule was primarily presented as a formula to calculate the ideal age of a female partner at the beginning of a heterosexual relationship. Frederick Locker-Lampson’s Patchwork from 1879 states the opinion “A wife should be half the age of her husband with seven years added.”[87] Max O’Rell’s Her Royal Highness Woman from 1901 gives the rule in the format “A man should marry a woman half his age, plus seven.”[88]
Although the provenance of the rule is unclear, it is sometimes said to have originated in France.[81] The rule appears in John Fox Jr.'s 1903 novel The Little Shepherd of Kingdom Come,[84] in American newspapers in 1931 attributed to Maurice Chevalier,[85] and in The Autobiography of Malcolm X, attributed to Elijah Muhammad.[86]
In many early sources, the rule was primarily presented as a formula to calculate the ideal age of a female partner at the beginning of a heterosexual relationship. Frederick Locker-Lampson’s Patchwork from 1879 states the opinion “A wife should be half the age of her husband with seven years added.”[87] Max O’Rell’s Her Royal Highness Woman from 1901 gives the rule in the format “A man should marry a woman half his age, plus seven.”[88]
https://en.wikipedia.org/wiki/Age_disparity_in_sexual_relationships
See I didn’t know that was the origin. I like it better as an outside boundary.
That’s really interesting, thanks for sharing!