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Start swiping — it's freeAfter the 1929 crash, the 1933 Banking Act's Glass-Steagall provisions forced commercial banks (which held deposits) and investment banks (which underwrote securities) to become separate companies, blaming the mix for reckless pre-crash lending. Congress repealed the separation in 1999 via the Gramm-Leach-Bliley Act, and economists still argue over whether that repeal helped set up the 2008 crisis.
Two colonels must each secretly split a fixed number of troops across several battlefields, deciding all at once with no knowledge of the other's plan. Whoever puts more troops on a given battlefield wins it outright, and whoever wins the most battlefields wins the war. Is there one 'best' way to divide your troops that beats every possible strategy your rival might choose?
No — there's no single dominant allocation. Any fixed split can be beaten by a rival who concentrates slightly more strength wherever you're thin, so the only equilibrium involves randomizing your allocation. Formulated by French mathematician Émile Borel in 1921 as an early model of competitive resource allocation, 'Colonel Blotto' games are now used to study election spending, advertising wars, and network defense.
Asked for one word to live by, Confucius reportedly answered 'reciprocity', then defined it in the negative: 'Do not impose on others what you yourself do not desire.' Unlike the Golden Rule's active version, this 'Silver Rule' doesn't risk projecting your own wants onto someone who wants something different.
In December 1938, chemists Otto Hahn and Fritz Strassmann found that bombarding uranium with neutrons produced barium, a far lighter element. Physicist Lise Meitner, then a Jewish refugee from Nazi Germany, worked out with her nephew Otto Frisch that the uranium nucleus had split in two. Hahn alone won the 1944 Nobel Prize in Chemistry for it; Meitner, nominated dozens of times, never did.
French soldiers found the Rosetta Stone in 1799 bearing a single decree repeated in Egyptian hieroglyphs, Egyptian demotic script, and Ancient Greek, which scholars could already read. Jean-François Champollion spent over a decade comparing the three versions, recognising that hieroglyphs mixed phonetic sounds with symbolic signs, and announced the decipherment in 1822, reopening three thousand years of Egyptian writing that had been unreadable since antiquity.
— Jean-François Champollion, Lettre à M. Dacier — 1822 letter announcing the decipherment