Many of the greatest works of philosophy seem to me to be valuable not because of their arguments, but because they offer us perspectives that open up new possibilities. They show us how we might start in different places, and not buy into the assumptions tacitly made on the first pages of the philosophical works that have influenced us.

Part of my methodological approach is made explicit when I discuss ways in which literature can have philosophical significance. Literature doesn't typically argue - and when it does, it's deadly dull. But literature can supply the frame within which we come to observe and reason, or it can change our frame in highly significant ways. That's one of the achievements I'd claim for Mann, and for Death in Venice.

In ethics, we don't make progress by discovering pre-existent truths; we do so by solving problems.

Read Mann's notes, which contain precise accounts of cholera and its symptoms, and observe how careful he is throughout his fiction in getting medical details straight - then you might begin to wonder whether cholera is the only candidate for the cause of Aschenbach's death. What results from this, I think, is a deeper appreciation of Mann's brilliance in keeping so many possibilities in play. The ambiguity is even more artful than people have realized.

When we read a literary work (or, in some instances, listen to music) our imagination is stimulated, we feel various emotions, and we arrive at new judgments. These attitudes are brought into relation with many others, including our standing tendencies to think and feel in particular ways, and we try to fit our psychological capacities and responses together.

There's a disciplined erotic component to it, so that the height of sexual contact is the embrace, the modest touch, a relatively chaste kiss. An important passage from the surviving 1942 diary (one I quote in the book) relates this mode of sexual expression to his own life. Mann had returned to his diary for 1927 (one of those he burned) and to his parting from the young man, Klaus Heuser, whom the family had met on holiday and invited to Munich.

Look at Mann's reading habits, his explicit comments on Nietzsche, and his copy of Birth of Tragedy, and it starts to seem doubtful that this work of Nietzsche's played much role in the gestation of the novella.