Leonardo da Vinci is considered to be one of the greatest minds of all times. His genius was driven by his insatiable curiosity, and his intuitive sense of the laws of nature. At age 17, Leonardo and his father moved to Florence where he had contact with other great Florentine artists including Michelangelo. In 1481 Leonardo left Florence for Milan to offer his service to the local Duke. During this period he painted the Virgin of the Rocks and the Last Supper. In 1499 Leonardo left Milan, traveling through Mantua, to the court of Isabella d'Este; to Venice, where he consulted on architecture from 1495 to 1499; and in 1502 and 1503 he was military engineer for Cesare Borgia.
After his service to the Borgias, Leonardo returned to Florence. It was during the period between 1503 and 1506, while working primarily in Florence, that he had his greatest following and painted such classics as the 'Mona Lisa'. After the death of Giuliano dei Medici, Leonardo accepted an invitation from French friends and moved to the castle of Cloux near Amboise, where he stayed with his faithful pupil Melzi until the end of his life. Leonardo helped set an ignorant and superstitious world on a course of reason, science, learning, and tolerance.
"Iron rusts from disuse; water loses its purity from stagnation and in cold weather becomes frozen; even so does inaction sap the vigors of the mind."
"As a well-spent day brings happy sleep, so life well used brings happy death."
"You do ill if you praise, but worse if you censure, what you do not understand."
"Patience serves as a protection against wrongs as clothes do against cold."
"In order to observe the nature of the planets, open the roof."