Leonardo's servant and assistant, Caprotti il Salaino by an anonymous artist (1495)
Gian Giacomo Caprotti da Oreno, nicknamed Salai or il Salaino ("The Little Unclean One" i.e., the devil), was described by Vasari as "a graceful and beautiful youth with fine curly hair, in which Leonardo greatly delighted." Il Salaino entered Leonardo's household in 1490 at the age of 10. The relationship was not an easy one. A year later Leonardo made a list of the boy's misdemeanours, calling him "a thief, a liar, stubborn, and a glutton." The "Little Devil" had made off with money and valuables on at least five occasions, and spent a fortune on apparel, among which were twenty-four pairs of shoes. Nevertheless, il Salaino remained his companion, servant, and assistant for the next thirty years, and Leonardo's notebooks during their early years contain pictures of a handsome, curly-haired adolescent.
Il Salaino's name also appears (crossed out) on the back of an erotic drawing (ca. 1513) by the artist, The Incarnate Angel, at one time in the collection of Queen Victoria. It is seen as a humorous and revealing take on his major work, St. John the Baptist, (based on Salaino's appearance) also a work and a theme imbued with homoerotic overtones by a number of art critics such as Martin Kemp and James Saslow  Another erotic work, found on the verso of a foglio in the Atlantic Codex, depicts il Salaino's behind, towards which march several penises on two legs. Some of Leonardo's other works on erotic topics, his drawings of heterosexual human sexual intercourse, were destroyed by a priest who found them after his death .
In 1506, Leonardo met Count Francesco Melzi, the 15 year old son of a Lombard aristocrat. Melzi himself, in a letter, described Leonardo's feelings towards him as a sviscerato et ardentissimo amore ("a deeply passionate and most burning love"). Salai eventually accepted Melzi's continued presence and the three undertook journeys throughout Italy. Melzi became Leonardo's pupil and life companion, and is considered to have been his favourite student.
Though Salai was always introduced as Leonardo's "pupil", the artistic merit of his work has been a matter of debate. He is credited with a nude portrait of Lisa del Gioconda, known as Monna Vanna, painted in 1515 under the name of Andrea Salai. The other portrait of Lisa del Gioconda, the Mona Lisa was bequeathed to Salai by Leonardo, a valuable piece even then, as it is valued in Salai's own will at ?200,000.
Both of these relationships follow the pattern of eroticized apprenticeships which were frequent in the Florence of Leonardo's day, relationships which were often loving and frequently sexual. (See Historical pederastic couples.) Besides them, Leonardo had many other friends who are figures now renowned in their fields, or for their influence on history. These included Cesare Borgia, in whose service he spent the years of 1502 and 1503. During that time he also met Niccol? Machiavelli, with whom later he was to develop a close friendship. Also among his friends are counted Franchinus Gaffurius and Isabella d'Este, whose portrait he drew while on a journey which took him through Mantua.
It is known that Leonardo da Vinci embraced vegetarianism at a young age, and remained so for the entire duration of his life.
It has been the subject of much speculation whether da Vinci was an orthodox Christian or whether he was a heretic. Many conspiracy theorists believe that he was "infected" with the Johannite heresy, that is he regarded not Jesus Christ but John the Baptist as the real Christ. This subject has also been the source for many best-selling books in recent times.
Representations in popular culture
Main article: Leonardo da Vinci in popular culture
With the genius and legacy of Leonardo da Vinci having captivated authors and scholars generations after his death, many examples of "da Vinci fiction" can be found in culture and literature. As of 2006, the most prominent example is Dan Brown's novel The Da Vinci Code (2003), which is concerned with Leonardo's role as a supposed member of a secret society called the Priory of Sion.
" Jean Paul Richter (1970). The Notebooks of Leonardo da Vinci. Dover. ISBN 0-486-22572-0 and ISBN 0-486-22573-9 (paperback). 2 volumes. A reprint of the original 1883 edition.
" Frank Zollner & Johannes Nathan (2003). Leonardo da Vinci: The Complete Paintings and Drawings. Taschen. ISBN 3-8228-1734-1 (hardback).
" Fred B?rence (1965). L?onard de Vinci, L'homme et son oeuvre. Somogy. D?pot l?gal 4° trimestre 1965.
" Charles Nicholl (2005). Leonardo da Vinci, The Flights of the mind. Penguin. ISBN 0-14-029681-6.
" Simona Cremante (2005). Leonardo da Vinci: Artist, Scientist, Inventor. Giunti. ISBN 88-09-03891-6 (hardback).
" John N. Lupia, "The Secret Revealed: How to Look at Italian Renaissance Painting," Medieval and Renaissance Times, Vol. 1, no. 2 (Summer, 1994): 6-17. (ISSN 1075-2110)
" Sherwin B. Nuland, "Leonardo Da Vinci." 176 P. Phoenix Press. 2001. ISBN 0-7538-1269-X
" Michael H. Hart (1992). The 100. Carol Publishing Group. ISBN 0-8065-1350-0 (paperback).
" Leonardo Da Vinci International Airport near Rome
" Leonardo da Vinci Art Institute, Cairo
" Luca Pacioli
" List of painters
" List of famous left-handed people
" List of Italian painters
" List of famous Italians
References & Notes
1. ^ Adherents.com article on Leonardo Da Vinci's religious beliefs.
2. ^ The U.S. Public Broadcasting Service (PBS), aired in October 2005, a television programme called "Leonardo's Dream Machines", about the building and successful flight of aglider based on Leonardo's design
3. ^ Sigmund Freud, Gesammelte Werke, bd VIII, 1909-1913
4. ^ Saslow, Ganymede in the Renaissance: Homosexuality in Art and Society, 1986, p.197
5. ^ E quante volte! Considera che egli era uno bellissimo giovane, e massime ne' 15 anni. Giovanni Paolo Lomazzo, "Il Libro dei Sogni;" (1563) in Scritti sulle arti; Centro DI, Firenze, 1974; vol 2, dialogue 5
6. ^ Oreno website (Italian)
7. ^ Saslow, ibid., passim)
8. ^ Augusto Marinoni, in "Io Leonardo", Mondadori, Milano 1974, pp.288,310
9. ^ Crompton, p.269
10. ^ Michael Rocke, Forbidden Friendships epigraph, p. 148 & N120 p.298
" History of Aerodynamics, John David Anderson, page 19. ISBN 521669553
" Giorgio Vasari's Lives of the Artists
" Birth of Modern Science, Paolo Rossi, page 33. ISBN 631227113
" Emperor Charles V, Impresario of War, James D Tracy, page 41. ISBN 0-521-81431-6
" Algebra in Ancient and Modern Times, V S Varadarajan, page 58. ISBN 0-8218-0989-X
" ArtNews article about current studies into Leonardo's life and works