You learn a word and then see it three times that week. The Baader-Meinhof phenomenon, where its odd name came from, and the two mental machines that make the world seem to rearrange itself around...
An infinite universe full of stars should make the whole sky blaze like the Sun. It doesn't. Olbers' paradox, the wrong answers it collected for 300 years, and the real reason the night is dark.
Seoul tore down a six-lane downtown highway and traffic got faster. That is Braess's paradox: how adding a road can slow everyone down, and removing one can speed a whole city up.
Everyone says QWERTY was built to slow typists down. The real story runs through jammed typebars, telegraph operators, and a standard too costly to replace.
A person shuffling symbols can answer fluently in a language they don't understand. That is Searle's Chinese Room, and it is the sharpest question we can ask about AI.
Fire electrons one at a time through two slits and they still interfere with themselves. What the double-slit experiment actually shows, and why 'observer' has nothing to do with your mind.