How Ancient China Used Torn Paper to Prevent Document Forgery

In ancient China, paper itself was used as proof to prevent document

forgery. Back then, there were no digital passwords

or modern security

technology, so some documents were torn by hand into two pieces.

The two pieces were then brought together and writing or a seal was placed across

the joint. One party kept one piece while the other party kept the other.

This meant that simply copying the writing and seal wasn't enough to forge a

document. A forger also had to match the irregular

torn edges of the paper because

the two torn edges had to fit together correctly, helping verify the document's

authenticity.