In the preface to his classic study of Leonardo da Vinci, Sigmund Freud warned of the danger of identifying too closely with one's subject. I am particularly conscious of this since I share a birthday with Giorgio Vasari. But this is an amusing coincidence rather than reason to write a book, especially given that Michelangelo probably would object to my portrayal of him, as he did to Vasari's.

In preparing to write a life of Michelangelo, I read more than a hundred biographies. Many were pedestrian affairs, but a few stand out in my mind as exceptional: Samuel Coleridge by Richard Holmes, James Joyce by Richard Ellmann, Berlioz by David Cairns, Maynard Solomon on Mozart and Beethoven, and Jack McClaughlin's biography of a house and its builder, Jefferson and Monticello. In bringing a subject sympathetically to life, Richard Ellmann's Oscar Wilde is an especially poignant and compelling portrait. This was the pleasurable part of my research, and it gave me the courage and conviction – although I have been writing on Michelangelo for more than twenty years – to attempt a modern biography of the artist.

During this book's long gestation, I naturally incurred many debts. For more than fifteen years, Paul Barolsky and Ralph Lieberman have been my constant companions in all things “michelangelesque” and “michelangeloid.” Especially pleasurable were the times I spent in Italy, sharing meals and long conversations with these and other dear friends: the late Philipp Fehl and his wife, Raina; Paul and Ruth Barolsky; Ralph Lieberman and Valerie Krall; Roy and Berit Eriksen; Eric Apfelstadt and Rebecca Edwards; and Mark and Phoebe Weil.