Joseph Ratzinger has a reputation as a crustily conservative theologian that is quite at odds with a sunny and witty personality. It also does not reflect the way in which over the past years he has been trying to develop the moral theology of the Catholic Church. He was presumably elected as a gesture of continuity with the legacy of John Paul II, to whom he was very close. What bound them was an intellectual affinity. Cardinal Ratzinger - who has chosen the papal name Benedict XVI - is a man of ideas, fascinated by the history of the papacy. Are there historical parallels to the present that might hold out some instruction?

In particular, he sees one 18th century pope (another Benedict) as a model for a Church in a self-consciously secular world. In the Enlightenment, belief was in rapid retreat. Cardinal Lambertini, the head of the Roman inquisition (whose successor, the Congregation of the Doctrine of the Faith, headed up to now by Cardinal Ratzinger) thought it was not enough for the church to be defensive. But if the church was to deal with a world in which active Christians were in a minority, it needed to convince others of the importance of what it was saying. It could no longer do this by force, but needed to use argument and rationality. So Lambertini corresponded with Voltaire, the greatest philosopher of the French Enlightenment, and maintained this dialogue when he became Pope Benedict XIV.