Sydney Smith's idea of heaven was eating pate de foie gras to the sound of trumpets. Sir John Mortimer, I believe, hopes to be drinking champagne in the Crush Bar of the Royal Opera House. Continuing the operatic theme, my idea of heaven would be standing on that stage and receiving tumultuous applause for my just-completed performance of Tosca. Yes, but what of the audience? Listening to me singing Tosca would be nobody's idea of heaven, so one has to assume that my appreciative hearers in this case would be, quite literally, the audience from hell. Already, the sheer difficulties about heaven - one person's bliss is another's torment - begin to emerge. The recent death of my father provoked in me the reflection that, as he had spent his life voluntarily among sinners, trying to succour them, he might find heaven on the dull side and therefore apply for transfer down below, to continue the good work.
In an engaging narrative in his new book, Peter Stanford explores all the complicated themes surrounding the subject. George Bernard Shaw, in Man and Superman (1903), understood the problem that I lightly supposed my father might feel: "Heaven, as conventionally conceived, is a place so inane, so dull, so useless, so miserable, that nobody has even ventured to describe a whole day in heaven, though plenty of people have described a day at the seaside."
As ever, the theory and workings of spiritualism provide some results that are bizarre to outsiders (the industrious Stanford went to a seance in the course of his researches). Sir Oliver Lodge, a leading British physicist and pioneer in the field of telecommunications, had always been interested in the subject, but the death of his son Raymond in 1916 made him a devotee of spiritualism, like many other bereaved parents. Raymond Lodge revealed to his father how matters had been arranged beyond the grave: "I know a man who has lost an arm, but he got another one . . . When anybody's blown to pieces, it takes some time for the spirit body to complete itself."
In The New Revelation, Arthur Conan Doyle, another devotee of spiritualism, wrote of something that Stanford describes as "rather like a Surrey golf club with drinks on tap and a constant supply of tobacco and congenial souls". A smoke-filled heaven may not be immediately appealing nowadays (surely an activity for the Other Place, where the ash and fumes will scarcely be noticed?), but Conan Doyle does earn one's gratitude by proposing that there are pets in heaven - a petless heaven being a contradiction in terms to many of us. This is as encouraging as Milton's view, expressed by the Archangel Raphael, that there will be lovemaking in paradise - not "casual fruition", but the angelic variety: "if Spirits embrace/ Total they mix, union of pure with pure". Still, better than nothing.
However, these and other sidelights, all fascinating, are not the main thrust of the book, which is in effect the history of the concept of life after death. (In the 1980s, a poll of westerners revealed that 71 per cent believed in this concept, only one percentage point down on a similar poll taken in 1952.) Stanford distinguishes between the three main approaches to the subject: first, the theocentric idea of a solitary, blissful union with God; second, the anthropocentric idea of "some overlap between heaven and earth, and hence relationships outside the central bond with God"; and third, a "cocktail" of the two - historically by far the most common approach - somewhere to be with God alone, yet also a place where the imagination provides a shape and form, very often a garden.
As Stanford points out, the churches (he writes as one who comes from the Judaeo-Christian tradition, although he also considers other, eastern religions) have never quite made up their minds. In July 1999, Pope John Paul II told pilgrims in St Peter's Square in Rome that heaven was not a place above the clouds where angels play harps, but "a living and personal relationship with the Holy Trinity . . . a blessed community of those who remained faithful to Jesus Christ in their lifetimes". This, while emphasising the vital connection of behaviour on earth to treatment in the afterlife, ducked the Catholic doctrine of purgatory, that period immediately following death when, according to the view the Catholic Church once held, the prayers of the faithful can affect the issue. Purgatory is - or was - a troubling doctrine, and the Church's sale of indulgences to the faithful to spare their loved ones too much time in purgatory was indeed one of the "abuses" that made Martin Luther seek our reformation.
The main difference of opinion on the afterlife is between those who believe that life on earth affects it (and therefore have a motive for behaving well, with promise of reward later) and those who do not see any such connection. In short, is it worth behaving well for the sake of what comes next? Although Stanford trails various accounts of out-of-body experiences, he does not - how can he? - provide an answer to this question. But it is worth reading his book for its elegant catalogue of the various future opportunities which may - or may not - be on offer.