Simon Singh · 1999

The Code Book

The Science of Secrecy from Ancient Egypt to Quantum Cryptography

Rough AI truth score

100/100

Its three central technical and historical claims hold up: language statistics break simple ciphers, Enigma was a cumulative Allied achievement, and public-key methods transformed digital security.

Based on three central claims · high confidence

The three claims

01Supported

Frequency analysis can break many monoalphabetic substitution ciphers because ciphertext preserves statistical patterns of the underlying language.

A fixed substitution changes symbols but preserves repeated letters, common digrams, and other distributional structure. Cryptanalysts can combine those frequencies with word patterns and context, although short texts and homophonic or polyalphabetic systems weaken the attack.

NSA: Military Cryptanalysis, Part I Rutgers: Classical Cryptography and Cryptanalysis

02Supported

Breaking Enigma was a cumulative Polish, French, and British effort rather than the achievement of a single codebreaker.

Polish mathematicians reconstructed Enigma and built the bomba before sharing their work with France and Britain in 1939. Turing, Welchman, and large Bletchley Park teams then extended that foundation against changing wartime systems and operating procedures.

GCHQ: The Pyry Forest Meeting NSA: Marian Rejewski

03Supported

Public-key cryptography solved central key-distribution and digital-signature problems and became foundational to secure digital communication.

Public-key systems let parties establish confidentiality and verify signatures without first sharing one secret key through a secure channel. Real systems still depend on authentication, implementation, and hybrid symmetric encryption, but the architectural breakthrough is accurately stated.

NIST: Public Key Cryptography NIST Cybersecurity History: Cryptography

Other claims worth checking

Cryptographic advantage repeatedly shifts between codemakers and codebreakers.
Quantum key distribution changes some security assumptions but does not replace all classical cryptography.

What this number means. It is an AI-generated first-pass judgment of three central factual or causal claims—not a rating, exhaustive fact-check, or human peer review. Claim credits are 100% for supported, 75% for mostly supported, 50% for mixed, and 25% for weak, then averaged and rounded. Lower confidence means the score should move more as better evidence arrives.

Method three-central-claims/0.1.0 · checked 2026-09-01 · 3/3 selected claims assessed · method and source audit