Today, across the dailies
Three daily surfaces I run, each on its own audience — a word and where it came from, a U.S. patent worth looking at, a paradox worth re-reading. Three independent rotations; this page is the editorial home that pulls today's pick from each. The dailies live where their readers find them; this is where they sit together.
rehearse
To rehearse is to go over a thing again before its real performance — to run the lines, walk the blocking, practice the speech. The word is, at the root, agricultural: Old French <em>rehercier</em>, "to harrow again," from <em>herce</em>, a harrow — the spiked frame dragged across a plowed field to break the clods and even the soil. To rehearse is to drag the rake back over ground you have already worked: a second pass over the same earth. The funeral <em>hearse</em> is the harrow's sibling — it began as a harrow-shaped frame of spikes set with candles over a coffin. And the farm implement called a <em>harrow</em> in English is, despite being the same tool, a false friend: a separate Germanic word. The word for practice is a word for re-tilling — working the same field a second time until it lies right.
Spatial Logical Toy
The Rubik's Cube. Rubik, a Hungarian sculptor and architecture professor, built the first prototype in his Budapest apartment in 1974 — to teach his students about three-dimensional geometry. He didn't realize it was a puzzle until he scrambled it and tried to put it back. It took him a month to solve. The Hungarian patent was filed 1975; the U.S. patent only in 1980 after the Cold War licensing tangle was resolved. By 1983, the year of the U.S. patent, more than 100 million had sold worldwide. The current speed-solving record is 3.13 seconds.
Simpson’s Paradox
A trend that appears in groups of data can disappear or reverse when the groups are combined.
The classic instance: in 1973, UC Berkeley’s graduate admissions appeared to favor men. Broken down by department, almost every department favored women. Women were applying disproportionately to departments with low admit rates. The aggregate trend was real; the per-department trend was real; both were correct, and they pointed in opposite directions. The paradox is most often presented as a statistical curiosity, but the deeper problem is that almost every “controlled for” claim in observational data depends on choosing the right grouping — and the data alone cannot tell you which grouping is right. The choice is causal, not statistical, and you cannot make it without a theory of how the world works. Simpson published the canonical 1951 paper; Pearson and Yule had stumbled into the same structure half a century earlier without naming it.