Cipherday #69 · August 31, 2026

The answer to Cipherday #69

The full three-cipher chain from August 31, 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

“A ship in harbor is safe, but that is not what ships are built for.”— attributed to John A. Shedd (1928)

Safety weighed against the whole purpose of setting out.

The cipher chain

1. Stage 1 · Caesar · Shift of 22

   Ciphertext

   Wzrajpqna eo sknpdsdeha ej epoahb.

   Decodes to

   Adventure is worthwhile in itself.

   Every letter was slid 22 places down the alphabet; sliding it back the same amount restores the line.

2. Stage 2 · Substitution · Keyword “COMPASS”

   Ciphertext

   Dkla er tda tdejb wetd sactdaqr.

   Decodes to

   Hope is the thing with feathers.

   A keyword scrambled the alphabet into a fixed cipher alphabet, so each letter always stands for the same partner — letter frequency gives it away.

3. Stage 3 · Vigenère · Keyword “SPHINX”

   Ciphertext

   S hoqc ff whzolj xz ancw, qbb gesi pa all loig pzxwa now qbqyq xdy.

   Decodes to

   A ship in harbor is safe, but that is not what ships are built for.

   A repeating keyword shifted each letter by a different amount, which is what lets one letter encrypt two ways; the right keyword resolves it.