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Diplomatics and Forgery Detection

History I 220 words Free to read

Diplomatics and Forgery

The Donation of Constantine supposedly transferred the Western Empire to the papacy. It underwrote papal claims for seven centuries until Lorenzo Valla demolished it in 1440.

Valla proved it a forgery using internal criticism alone, anchoring it to its actual date of creation.

Flaw TypeWhat Valla Found
LanguageEighth-century Latin, not fourth-century
VocabularyAnachronistic offices and titles
SilenceNo contemporary source mentions it

A forgery carries the fingerprint of its maker, because a forger cannot help writing in their own language and knowing their own world.

The Anatomy of a Document

Founded by Jean Mabillon in 1681, diplomatics dissects documents into formal parts. Forgers consistently mess up these tight chancery conventions.

PartContainsForger's Tell
ProtocolInvocation, greetingWrong formula
TextPreamble, dispositionAnachronisms
EschatocolDate, sealImpossible dates

External criticism examines the physical object, while internal criticism examines content.

The Tell: Forgeries are over-explicit, answering present disputes too perfectly. Crucial complication: Most medieval forgeries backed true claims after old charters burned. The forgery is still evidence, just of the moment it was forged.

A charter taken apart into its three parts, each with its own tell

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Historical Sources