Cipherday #55 · August 17, 2026
The answer to Cipherday #55
The full three-cipher chain from August 17, 2026, the public-domain quote it hid, and how each cipher worked. Today’s chain stays sealed until it becomes a past day.
The revealed quote
“The best time to plant a tree was twenty years ago; the next best is now.”— proverb in the Chinese tradition
A famous nudge to start today what should have started long ago.
The cipher chain
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Stage 1 · Caesar · Shift of 14
Ciphertext
Sjsfm rcu vog whg rom.Decodes to
Every dog has its day.Every letter was slid 14 places down the alphabet; sliding it back the same amount restores the line.
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Stage 2 · Substitution · Keyword “COMPASS”
Ciphertext
C okkg dkhpr c dkura ks bkhp.Decodes to
A book holds a house of gold.A keyword scrambled the alphabet into a fixed cipher alphabet, so each letter always stands for the same partner — letter frequency gives it away.
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Stage 3 · Vigenère · Keyword “HALCYON”
Ciphertext
Ahp dcgg aixg rc csayv y hele hcq hjlnea wsnys lim; hul npzr przt tu lcj.Decodes to
The best time to plant a tree was twenty years ago; the next best is now.A repeating keyword shifted each letter by a different amount, which is what lets one letter encrypt two ways; the right keyword resolves it.