'PERHAPS WHAT is inexpressible (what I find mysterious and am not able to express)', wrote Wittgenstein, 'is the background against which whatever I could express has its meaning'. Wittgenstein's remark is a useful reminder to all who attempt to write about the nature and the value of art, for there our powers of expression often seem inadequate to the phenomena we aim to describe. In such cases it is natural to direct attention to the 'background' of aesthetic experience itself. In consequence, many philosophical elucidations of art works will make good sense only to whose who are already engaged with them on their own terms—engaged with their distinctive character and forms. That this is so is perhaps most evident when the philosopher's t...