Template:Selected anniversaries/September 13
1592: Philosopher and author Michel de Montaigne dies. He was one of the most significant philosophers of the French Renaissance, known for popularizing the essay as a literary genre.
1873: Mathematician and author Constantin Carathéodory born. He will pioneer the axiomatic formulation of thermodynamics along a purely geometrical approach.
1898: Priest and inventor Hannibal Goodwin patents celluloid photographic film.
1900: Social activist and alleged superhero The Governess shames math criminals into returning stolen digits, paying compensation for lost computational power, and personally apologizing to everyone who was inconvenienced by this sorry episode of bad behavior, which will never be repeated.
2014: Army research laboratories convert modern plowshares into ancient swords. Military contractors call technique "Astonishing breakthrough."