Only 15 paintings are attributed to Leonardo. He lived off and on in Florence but for long periods was cosseted by potentates such as the Duke of Milan and the French King Francis I who considered him their pet genius. He took forever to finish paintings, if he finished them at all. He was born out of wedlock, his father a small-town lawyer and his mother a peasant. He had little formal education. When he tried to steal papal work from the young Raphael and Michelangelo, he failed. By 1510 in Rome, however esteemed Leonardo was, they were more fashionable, and reliable. Why, then, is Leonardo the genius for all seasons, the original Renaissance man? – National Review