Drinking from the Hoover Dam
Think of a thing. Anything. The rule is that I get to ask you questions — yes/no answers only — and I have twenty of them. Anyone whose childhood happened in the nineties, or not much later, will remember Akinator and its many cousins: officially it came out a few years afterwards, but the idea it stands on is far older than that. What few people notice is that if I play well — which really means, if every question cuts in half whatever is left — twenty answers are enough to find one object in a million. And the reason is embarrassingly simple: ...