The English composer Michael Tippett was described by the philosopher Isiah Berlin as “a major asset to our age, morally as well as aesthetically” and when he died in 1998 he was lauded in obituaries as ‘one of the greatest English composers since Elgar’.Tippett, whose music includes the oratorio A Child of Our Time, five operas and four symphonies, is considered to be among the most ‘visionary’ of the twentieth century, and yet, says author Oliver Soden, since his death he has been under app...