World Origins of Cryptography
Writing, concealment and encipherment across Egyptian, Hebrew, Greek, Roman, Indian and Arabic traditions
Early writing traditions include concealment, signaling, language decipherment and deliberate encipherment. These are related topics, not interchangeable evidence of encryption. This hall identifies the historical sources and the limits of each modern demonstration.
What this hall teaches: The surviving sources describe different problems: hiding a message, signalling it, substituting symbols and deciphering an unfamiliar script. Similarity between methods does not by itself establish a shared origin or direct transmission between cultures.
Suggested route: Start with Egyptian Substitution and the Rosetta Stone to separate unusual writing from language decipherment. Continue through Histiaeus, Scytale, Atbash and Caesar, then compare al-Kindi’s documented cryptanalytic methods.
Unusual writing in Khnumhotep II’s tomb: an early example discussed in cryptographic histories, without an established modern secrecy purpose.
The Rosetta Stone (196 BCE) records a decree in two languages and three scripts. It supported the decipherment of Egyptian hieroglyphs; it is not an encryption system.
Histiaeus of Miletus (~499 BCE) — the Greek tyrant who tattooed a secret revolt order on a slave's shaved scalp, then waited for the hair to regrow before sending him.
The traditional scytale reconstruction illustrates transposition, but the dates and cryptographic interpretation of ancient evidence are disputed.
READ: HDUEANPTTDMAECREITAK
Suetonius describes Caesar’s use of a three-letter shift. The modern 26-letter exercise has only 26 shifts to test; it does not require a ninth-century attack.
SHIFT: +3
CIPH: KHOOR
Polybius describes alphabetic torch signalling using five tablets for the Greek alphabet. The displayed I/J grid is a modern Latin-alphabet adaptation.
HELLO = 23 15 31 31 34
Atbash — the ancient Hebrew reflection cipher (A<->Z, B<->Y, C<->X), self-inverse and used in the Book of Jeremiah (25:26, 51:41) for SHESHACH.
HELLO = SVOOL
Mlecchita-vikalpa, secret writing among the Kama Sutra’s arts. The interactive illustrates a modern paired-letter substitution, not a recovered ancient alphabet.
Aeneas’s water-clock signaling, preserved in Polybius: synchronized vessels selected preset military messages, not letters of an alphabet.
Arabic cryptanalytic scholarship and a teaching model of nomenclators: frequency analysis, codewords, and the need to identify a particular historical key.
ROT13 (~1983, Usenet) — the self-inverse Caesar with shift 13, designed as a spoiler obscurer rather than a cipher. One operation toggles text in and out.
Foundational Concepts
The Caesar cipher wraps around the alphabet using modulo 26. (position + shift) mod 26. Modular arithmetic appears throughout cryptography; AES uses binary finite-field operations rather than addition modulo 26.
Polybius’s coordinate notation separates a symbol into row and column information. Later fractionating ciphers rearrange such coordinates; modern bitslicing is a different implementation technique.
Fixed substitutions preserve symbol counts while relabeling them. Frequency comparisons can suggest a key, especially with longer text, but short samples may not follow average language frequencies.