A quartet of leading atheist intellectuals, including the dense French theorist Julia Kristeva and our own AC Grayling, were due to bejoining the Pope at a major inter-faith event  in Assisi next week. The gathering is designed to celebrate the twenty-fifth anniversary of John Paul II's 1986 World Prayer Day, a colourful event in which the late pontiff was joined by, among others, Archbishop Robert Runcie, the Dalai Lama and a handful of tribal shamans to pray for world peace. There were no atheists on that occasion, though. Nor Miss World, as far as I'm aware.
For Pope Benedict, there may be a tactical reason for the inclusion this time of non-believers in any kind of God. His predecessor was criticised heavily by some traditionalists for praying alongside representatives of other faiths, especially non-monotheistic ones. To this day, dissident Catholics enjoy circulating pictures of John Paul being "blessed" by Native American chiefs and voodoo witchdoctors. The then Cardinal Ratzinger was one the only leading Vatican official who didn't travel to Assisi , and later wrote that the meeting gave a "false impression of common ground that does not exist in reality".
His own writings and speeches have tended to stress the differences between faiths rather than the similarities. He has even suggested that inter-religious dialogue is impossible since different religions can never agree on the truth. There have been some tricky inter-faith moments since he became pope -- most notably in the wake of a speech in Regensburg in 2006 in which he appeared to criticise Islam. This year's Assisi gathering is being described as a "pilgrimage" rather than a prayer event. And what better way could there be to indicate the non-theological nature of the meeting than to invite atheists?
There are signs, too, that Pope Benedict XVI finds the company of non-believers quite congenial. He is, after all, a man who relishes intellectual debate and is known to be uncomfortable with the woolly, feelgood platitudes that constitute many inter-faith discussions. Atheists might liven things up a bit. Perhaps he hopes that some will prove to be allies.
"The pope wanted the atheists in Assisi," said Cardinal Gianfranco Ravasi, who leads the Pontifical Council for Culture, which now includes a division dubbed the Court of Gentiles dedicated to fostering good relations with humanists. Ravasi went on to explain the move as part of the pope's ongoing project "to reassert the importance of the relationship between faith and reason." The problem for the Church in modern Europe, he said, wasn't atheist thought so much as the general atmosphere of "indifference, dullness, lack of questioning, banality" that characterises modern culture. This echoes recent comments the pope made in Germany, when he suggested that agnostics who struggle with the question of God are closer to the kingdom of God than "routine" Catholics whose faith is purely conventional.
Earlier this year, the Vatican launched a series of international seminars  with the aim of finding common ground with secularists on the big questions facing modern societies. This may be indicative of a wider trend in which atheists and agnostics are beginning to claim a place in the growing world of inter-faith activities. Rory Fenton, for example, recently argued  that there is a "gaping atheist-shaped hole in the interfaith movement".
But it would be going too far to suggest that we are witnessing a Catholic/atheist love-in. For one thing, the pope has regularly denounced "atheist extremism", even associating it with the rise of Nazism. For many of today's most prominent atheists, meanwhile, Joseph Ratzinger remains Enemy Number One, "a leering old villain in a frock" as Richard Dawkins once notoriously described him. Everywhere he goes these days, he is followed by demonstrators, mostly avowed atheists, objecting to his views on contraception or calling for his arrest. Grayling  himself last year linked Pope Benedict with the CEO of Goldman Sachs, "each heading organisations publicly acknowledged to have done immense harm and yet neither is in any danger of having to pay for it."
It would have been interesting to see whether AC said anything like that in the Pope's presence. Sadly, it's now being reported that he has pulled out of the event . He now says that he had not realised that it was "a minor event and what they wanted was these guests to accompany the pope on a pilgrimage." This is rather puzzling, given that the event he was invited to was officially described as "a panel discussion" and may not -- for the atheists at least -- have included a trip to Assisi at all. It may be a simple matter of miscommunication, or perhaps Grayling had other reasons for pulling out. The other atheists, though, will probably still be there.
UPDATE 3pm: This blog was updated to reflect the news that AC Grayling had pulled out of the event.