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Start swiping — it's freeJakobshavn Isbræ, on Greenland's west coast, is one of the fastest-moving glaciers on Earth, discharging huge volumes of ice into Disko Bay each year. Ocean currents carry icebergs from that bay south along a well-documented drift path, and researchers have identified it as the most likely source of the iceberg that sank the Titanic in 1912, though no direct proof can ever confirm which exact iceberg was responsible. It remains one of the single largest sources of Greenland's ice loss today.
— Wikipedia contributors, Jakobshavn Glacier — Standard glaciological accounts; iceberg drift research
Look at a drawing of a triangle made from three beams that each look straight and connect at right angles — yet the whole shape loops back on itself in a way no real solid object could. Why does this look so convincing, and can it actually be built?
It can't exist as a rigid solid in ordinary three-dimensional space — each corner is locally consistent, but the drawing cheats perspective globally, so the three corners can never agree on a single 3D shape. Swedish artist Oscar Reutersvärd drew the first version in 1934; psychiatrist Lionel Penrose and his son, mathematician Roger Penrose, independently rediscovered it and published it in 1958, calling it 'impossibility in its purest form.' M.C. Escher used it soon after in his 1961 lithograph Waterfall.
Old and Middle English used a letter called thorn (Þ) to write the 'th' sound, as in 'the'. When printing presses arrived from continental Europe without a thorn character, printers substituted the visually similar letter Y, producing abbreviations like 'ye' for 'the'. It was always meant to be read and said as 'the' — the pseudo-archaic 'ye' pronunciation used in mock-historical shop names today is a much later misreading.
Opportunity cost is the value of the next-best option you give up when you make a choice — not just the cash you spend. Spending an evening studying costs you that evening's sleep or socializing; a factory devoting a production line to one product costs it the revenue the other product would have earned. Austrian economist Friedrich von Wieser formalized the concept in the late 19th century, and it now underlies nearly every basic economic trade-off analysis.
— Friedrich von Wieser, Der natürliche Werth (Natural Value) — 1889
Wilhelm Wundt opened the first laboratory built specifically to study the mind experimentally, treating reaction times and sensations as measurable data rather than philosophy. He trained the first generation of PhD psychologists there and founded the field's first academic journal. A 1991 survey of historians ranked him the single most eminent figure in psychology's history.
— Wilhelm Wundt, Wilhelm Wundt — Institute for Experimental Psychology, University of Leipzig, 1879