A stopped clock vs. one losing a minute a day — which is right more often?
You're offered two broken clocks. One has stopped completely and never moves at all. The other still runs, but loses exactly one minute every day. If what matters is how often a clock actually shows the correct time, which one should you pick?
Reveal the answer
The stopped one, by a landslide. It shows the correct time twice every 24 hours, the moments the real time matches wherever its frozen hands happen to point. The clock losing a minute a day has to fall a full 12 hours (720 minutes) behind before it's accidentally correct again — which takes 720 days, so it's only right once every two years. Lewis Carroll posed this as "The Two Clocks" in The Rectory Umbrella, a magazine he handwrote as a teenager, c. 1850-1853 (first published 1932).
— Lewis Carroll (Charles Lutwidge Dodgson), The Rectory Umbrella — "The Two Clocks," c. 1850-1853; first published 1932
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