Leon Battista Alberti (Italian: [leˈom batˈtista alˈbɛrti]; February 14, 1404 – April 25, 1472) was an Italian Renaissance humanist author, artist, architect, poet, priest, linguist, philosopher and cryptographer; he epitomised the Renaissance Man. Although he is often characterized exclusively as an architect, as James Beck has observed, "to single out one of Leon Battista's 'fields' over others as somehow functionally independent and self-sufficient is of no help at all to any effort to characterize Alberti's extensive explorations in the fine arts." Although Alberti is known mostly for being an artist, he was also a mathematician of many sorts and made great advances to this field during the 15th century. Alberti's life was described in Giorgio Vasari's Lives of the Most Excellent Painters, Sculptors, and Architects. His two most important buildings are the churches of S. Sebastiano (1460) and S. Andrea, both in Mantua.