Every reader feels a sense of achievement on completing a book, which is why short books please. The pleasure of achievement comes without the pain of labor, and if we feel that we have cheated slightly by having chosen the easy path we can console ourselves that shortness is not necessarily shallowness. Descartes’s Discourse on Method, for example, is a very short book.

Alexander McCall Smith’s book on W. H. Auden is very short and pretends neither to the status of biographical guide to the poet’s work, nor profound criticism of it. Rather it is the record of a personal response to it, made in the hope that this will encourage people either to go to the poet for the first time or return to him with renewed enthusiasm. McCall Smith is something of an evangelist on the poet’s behalf.

Some of the author’s reflections are indeed not very profound,...