True

Leonardo da Vinci wrote in code: When jotting down ideas, Da Vinci often wrote from right to left, a type of mirror writing that makes his manuscripts hard to read. The fact that he used shorthand doesn't help, either.

The artist's Adoration of the Magi was painted and modified by another, unknown hand. Dan Brown has this right, and he is correct in identifying Italian art analyst Maurizio Seracini as the researcher who penetrated beneath the painting's layers of pigment and discovered this.

Da Vinci was not necessarily responsible for every "Leonardo." Because of the studio apprenticeship system, it was common for other artists to complete a commission.

Da Vinci saw the wonders of the Earth as the creation of nature, not God. Yale Prof. Sherwin B. Nuland points out that Da Vinci came surprisingly close to describing the theory of evolution.

No one knows why Mona Lisa is smiling. In fact, some people don't think she is.

False

The character on Jesus's right in The Last Supper is Mary Magdalene. It's John. Despite spirited arguments by authors Lynn Picknett and Clive Prince, whose books Dan Brown used in his research, there's no reason to think Da Vinci deviated from the normal grouping in Last Suppers of his age. And whatever he thought of Mary Magdalene at the time, he was perfectly content to paint her in the traditional way 15 years later.

Da Vinci was a secret devotee of the Knights Templar and a grand master of the Priory of Sion. Only if you believe the Dossiers Secrets. Check out the link under "The Priory of Sion."

Da Vinci's output of Christian art was "breathtaking." In fact his reputation is based on fewer than two dozen surviving paintings–relatively few compared with other great artists.

The artist left coded messages in his paintings. There's no evidence for this. Among the more far-fetched suggestions is Brown's contention that the name of the Mona Lisa is a code and can be rearranged to become Amon L'isa, a supposedly androgynous union. Unlikely: The name Mona Lisa (Mona is a contraction of Madonna) dates from well after Da Vinci's death.

In the world of art, people routinely refer to "Da Vinci." Actually, your average teaching assistant in Art Appreciation 101 is likely to wince at any reference other than "Leonardo." "Da Vinci" indicates the town he came from.