Extended interview: Grateful Dead co-founder Bob Weir

Nearly 60 years after Bob Weir helped form the eclectic rock group The Grateful Dead in Palo Alto, Calif., the music of the Dead is being adapted for the concert hall. In this extended interview, correspondent John Blackstone talks with Weir, now 75, about the Dead’s music, adapting it to performance by a symphony orchestra, the curious life of a song “critter,” and the unfinished business resulting from bandmate Jerry Garcia’s passing.