For 500 years the State Oracle of Tibet has worked as a kind of angry immortal advisor to the Dalai Lama, a Tibetan hybrid of Dominic Cummings and John Dee. The current incumbent, like all previous ones, alternates between his human incarnation and his spirit version. ‘In Tibetan Buddhism, the unseen parallel world of spirits is not to be taken lightly,’ explains anthropologist David Sneath on Heart and Soul (BBC World Service).