Original: Eugene Muntz , Leonardo da Vinci Artist , Thinker , and Man of Science ( 1898 ) , quoted at Leonardo da Vinci 's Ethical Vegetarianism Leonardo had many friends who are now renowned either in their fields or for their historical significance .
Simplified: Eugene Muntz , Leonardo da Vinci Artist , Thinker , and Man of Science ( 1898 ) , quoted at Leonardo da Vinci 's Ethical Vegetarianism Very little is known about Leonardo 's life and work between 1472 and 1481 .