In 1970 a scraggly, antiheroic man from North Carolina by way of Massachusetts began presenting a comforting yet biting new sound. Within a year, when young ears sought the latest in rock, there was "Fire and Rain" and "You've Got a Friend," and a new Southern California-fed branch of pop music. James Taylor was its reluctant leader. Remarkably, Taylor has survived: his 2015 release, Before This World, edged out Taylor Swift and went...