I had no idea that there were instructional texts behind the major figures of the Italian Renaissance, it's a shame that this isn't more popular than it is. To introduce these concepts to major artistic figures like Leonardo da Vinci and Michaelangelo was to give life to the early modern world and something to enjoy visually for generations to come. Of course this should be preserved, we can only hope that future generations will take strategies from this text and imprint a sense of our society's context onto a canvas or other mode of art with the beauty that these artists executed. 
How come this isn't more popular than it already is? And how do modern artists feel about this text?