From Secrets of the Code

Da Vinci: Father of Cryptography

Ever looked at the Mona Lisa and wondered why he's got such a goofy grin? Yes, we do mean he.

Evidently, Mona isn't quite the woman art historians thought she was. But only those who know the secret code can look at Leonardo da Vinci's famous portrait and see the happy hermaphrodite that lurks within. Dan Brown's latest novel, The Da Vinci Code, is about the famous Renaissance artist and the oblique references to the occult contained in his equally famous paintings. It's also about ancient secret societies, modern forensics, science and engineering, and the history of religion.

Most of all The Da Vinci Code is about the history of encryption -- the many methods developed over time to keep private information from prying eyes. The novel begins with Harvard symbologist Robert Langdon receiving an urgent late-night phone call: The elderly curator of the Louvre has been murdered inside the museum.

Near the body, police have found a secret message. With the help of a gifted cryptologist, Langdon solves the enigmatic riddle. But it's only the first signpost along a tangled trail of clues hidden in the works of Leonardo da Vinci. If Langdon doesn't crack the code, an ancient secret will be lost forever.

Brown's characters are fictional, but he swears that "all descriptions of artwork, architecture, documents and secret rituals in this novel are accurate." The author provides detailed background on the novel's historic basis on his website, but he suggests readers finish the book before reviewing the site, which gives away some of the plot's twists.

The book's publicity hints darkly that the story lays bare "the greatest conspiracy of the past 2,000 years." Perhaps, but anyone who is interested in conspiracy theories won't find anything new here.

Where The Da Vinci Code does shine -- brilliantly -- is in its exploration of cryptology, particularly the encoding methods developed by Leonardo da Vinci, whose art and manuscripts are packed with mystifying symbolism and quirky codes.

Brown, who specializes in writing readable books on privacy and technology, cites da Vinci as an unheralded privacy advocate and encryption pioneer. His descriptions of da Vinci's cryptology devices are fascinating.

Throughout history, entrusting a messenger with a private communication has been rife with problems. In da Vinci's time, a major concern was that the messenger might be paid more to sell the information to adversaries than to deliver it as promised.

To address that problem, Brown writes that da Vinci invented one of the first rudimentary forms of public-key encryption centuries ago: a portable container to safeguard documents.

Da Vinci's cryptography invention is a tube with lettered dials. The dials have to be rotated to a proper sequence, spelling out the password, for the cylinder to slide apart. Once a message was "encrypted" inside the container only an individual with the correct password could open it.

This encryption method was physically unhackable: If anyone tried to force the container open, the information inside would self-destruct.

Da Vinci rigged this by writing his message on a papyrus scroll, and rolling it around a delicate glass vial filled with vinegar. If someone attempted to force the container open, the vial would break, and the vinegar would dissolve the papyrus almost instantly.

Brown also brings readers deep into the Cathedral of Codes, a chapel in Great Britain (Rosslyn Chapel, Scotland—ed.) with a ceiling from which hundreds of stone blocks protrude. Each block is carved with a symbol that, when combined, is thought to create the world's largest cipher.

"Modern cryptographers have never been able to break this code, and a generous reward is offered to anyone who can decipher the baffling message," Brown writes on his site.

"In recent years, geological ultrasounds have revealed the startling presence of an enormous subterranean vault hidden beneath the chapel. This vault appears to have no entrance and no exit. To this day, the curators of the chapel have permitted no excavation."

Brown specializes in literary excavation. His previous books have all involved secrets -- keeping them and breaking them -- and how personal privacy slams up against national security or institutional interests.

He's written about the National Reconnaissance Office, the agency that designs, builds and operates the nation's reconnaissance satellites. He's also written about the Vatican and the National Security Agency.

Brown's first novel, Digital Fortress, published in 1998, details a hack attack on the NSA's top-secret super computer, Transltr, which monitors and decodes e-mail between terrorists.

But the computer can also covertly intercept e-mail between private citizens. A hacker discovers the computer and takes it down, and demands that the NSA publicly admit Transltr's existence or he'll auction off access to the computer to the highest bidder.

"My interest in secret societies sparks from growing up in New England, surrounded by the clandestine clubs of Ivy League universities, the Masonic lodges of our Founding Fathers and the hidden hallways of early government power," Brown said. "New England has a long tradition of elite private clubs, fraternities and secrecy."


This article originally appeared in WIRED Magazine, April 2003, shortly after The Da Vinci Code was first published. Michelle Delio is a journalist who has frequently written about encryption, internet security, hackers, spam, privacy and related topics. Reprinted from Wired News, Copyright @ 2003 Wired Digital Inc., a Lycos Network Company. All rights reserved.