Cipher Cross-off List
Purpose
Previous studies into the Tamam Shud case have concluded that the mysterious code left behind is not just random letters; it is in fact a code. This raises the question: What code was used in encrypting this code? This page is aimed at addressing this question. The Cipher Cross-off list is a place where cipher schemes are listed that have been identified as potentially being used in creating the Somerton Man's code. As part of our project, we will be methodically investigating many of these listed ciphers to see if we can rule them out as being used in the encryption of the code.
Cipher Cross-off List
- Anagram/Transposition Cipher
- Initial letters of an unordered list
- Initial letters of a sentence
- Random Sequence of letters
Substitution Ciphers
- Playfair Cipher
- Trifid Cipher
- Bifid Cipher
- Vigenere Cipher
- One Time Pad
- Two-square Cipher
- Four-square Cipher
First Order Substitution Ciphers
- Alphabet Reversal Cipher
- Caesar Cipher
- Affine Cipher
- Book Cipher
- Null Cipher
Stream Ciphers
- Auto-Key Cipher
Substitution and Transposition Ciphers
- ADFGVX Cipher
- VIC Cipher
Reasoning
The following section contains the explanations and/or proofs behind the ruled-out ciphers.
Anagram/Transposition Cipher
By looking at letter frequency plots of various languages against the code, and by identifying other anomalies such as the existence of a 'Q' but no 'U' in the code, the Honours students in 2009 concluded the code did not use a Transposition Cipher alone. The relevant section of their report can be seen here.
Random Sequence of Letters
As part of their work, the students undertaking this project in both 2009 and 2010 conducted surveys of both sober and intoxicated people to see if the letter frequencies obtained were similar to the letter frequencies evident in the Somerton Man's code. Neither of the groups' surveys were consistent with the code and subsequently it was concluded that it is not simply a random bunch of letters. The relevant sections of the previous groups' work can be seen at the following links: 2009: The letters are not random 2010: The letters are not random