By Mary Carole McCauley American jazz icon Herbie Hancock remains exactly where he always has been – at the forefront of his field, observing, innovating and asking unnerving questions of himself and everyone he encounters. At 86, Hancock has been performing music and composing it for a very, very long time. Seventy-four years to be exact, if you count the former child prodigy’s debut playing piano with the Chicago Symphony Orchestra in 1952. Along the way, he has won numerous accolades,...