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Start swiping — it's freeIn April 1815, Mount Tambora in Indonesia erupted in the most powerful blast in recorded history, throwing enough ash into the atmosphere to lower global temperatures the following year. 1816 became the 'Year Without a Summer': snow fell in June across New England and Europe, harvests failed, and a group of writers trapped indoors by the freak weather in Switzerland included Mary Shelley, who began writing Frankenstein that same wet summer.
— Gillen D'Arcy Wood, Tambora: The Eruption That Changed the World — 2014
Two glasses hold equal amounts of wine and water. Take a spoonful of wine and stir it into the water glass. Then take a spoonful of that new mixture and stir it back into the wine glass. Without knowing the spoon's size, or how thoroughly it was stirred either time: is there now more water sitting in the wine glass, or more wine sitting in the water glass?
They're exactly equal, regardless of the spoon's size or how well anything got mixed. Both glasses end up holding their original volume again, so whatever wine is missing from the wine glass has to be somewhere — and the only place it can be is the water glass, displacing precisely as much water as crossed over the other way. Martin Gardner popularized this in his Scientific American column (1957), collected in Hexaflexagons and Other Mathematical Diversions (1959).
A language is considered dead the moment its last fluent speaker dies, or its last community shifts to another tongue. More than half the world's endangered languages sit in just eight countries, and linguists estimate a substantial share of the roughly 7,000 languages spoken today could fall silent this century, mostly through gradual generational shift rather than dramatic events. Once a language dies undocumented, the knowledge and worldview encoded in it are usually lost for good.
Lake Vostok lies under nearly 4km of East Antarctic ice, kept liquid by geothermal heat despite the deep freeze above. Confirmed by seismic and satellite surveys in the 1990s, its water has been isolated from the atmosphere for an estimated 15 to 25 million years, making it one of Earth's closest analogues to the buried oceans suspected beneath Jupiter's moon Europa.
Richard Easterlin found that within any country, wealthier people report more happiness — but as whole nations get richer over decades, average happiness barely budges. His explanation: people judge their income against others', so when everyone's income rises together, relative status stays the same.