Harvard faculty-member and Beethoven expert “was a great-grandson of Ralph Waldo Emerson, combined a Yankee sense of duty with an un-Yankee-like personal warmth. A daily attendee at morning prayers at Harvard’s Appleton Chapel, Mr. Forbes was a trustee of the New England Conservatory and board member of the Pro Arte and the Isabella Stewart Gardner Museum (the museum’s piano is dedicated in Mr. Forbes’s name).”