Public index · Cipher
FISH
24 | 42
English FISH. Reduction 24. Ordinal 42. Babel fish in the Guide.
FISH is 24 on one face and 42 on the other. Adams’s own sentence: small, yellow, leech-like. Not a goldfish. In the Guide you put it in your ear and suddenly understand Vogon poetry, which is not an improvement.
Other paperwork · the Guide
Arithmetic reviewed. Situation not improved.

The kitOpen the paperwork
DON’T PANIC42
Large friendly letters. English reduction. Reverse is 48. Face-specific. Panic accordingly, but nicely.
DEEP THOUGHT42
Seven and a half million years. Then an ordinary smallish number. The name reverse-reduces to 42 as well, which the computer has filed under Coincidence, Galactic, Mildly Irritating.
HUMANITY111 · 42
Ordinal 111. Reverse 42. Same two faces as HESPERUS. Not a proof. A paperwork problem.
DOLPHIN42
Second most intelligent. They knew. They left. Typical.
FISH24 | 42
Put it in your ear. Suddenly you understand Vogon poetry, which is not an improvement.
TOWEL24
Most massively useful. Always know where it is. 24 would also have done. He did not pick 24.
MICE24
Most intelligent. They were running the experiment. Do not tap the glass.
GROK ME69
Ordinal. A 69 sitting next to a 42, as if the forms had been shuffled in transit.
In the books, not the cipher: the Answer after 7.5 million years; 6 × 9 (base 13, which Adams later declined to be proud of); Milliways table 42; number 42 at Club Beta; a puzzle of 42 balls, built because people would not stop looking.
What it supports
Two named English faces of one word. Reduction 6+9+1+8 = 24. Ordinal 6+9+19+8 = 42. CIPHER owns the arithmetic. Adams owns the creature: small, yellow, leech-like, probably the oddest thing in the Universe. The 1981 BBC prop was latex, about an inch and three quarters.
What it does not
Not a zoological 42. Not proof the Guide was a cipher manual. Two faces, one fish.
Calculation
Reduction F6+I9+S1+H8 = 24. Ordinal F6+I9+S19+H8 = 42.
English full reduction and English ordinal
ExactnessCipher result
FormComposite 24 | 42
Unitcipher
Strengthreproducible