Keynes: The Return of the Master is one of those books that induces in the willing reader a mixture of admiration and exasperation. It is, so to speak, two potentially wonderful books that have been half-finished in too much of a hurry. Which is to say that it is well worth reading for its many good moments, but it doesn’t deliver the knockout punch it aims for.

Why might we be willing readers in the first place? Robert Skidelsky is the author of one of the most astonishing biographies of the past fifty years: more exactly, his monumental life of John Maynard Keynes is a triple masterpiece. Its achievement is that it not only does