Jomier admires Theo for the clarity with which he assesses the good and the evil of the smallest actions in everyday life. How much more enjoyable is lunch at the Athenaeum when one knows that each mouthful is, in some small sense, a good work. Theo has not only expressed these views to Jomier but to a wider audience through talks to the Oxford Newman Society and articles in the Telegraph, the Spectator and the Salisbury Review. They enrage his Catholic co-religionists who, since the Second Vatican Council, have put all their eggs in the basket of social reform. Their Jesus is a Nye Bevan of antiquity; his curing of lepers a pilot for the National Health Service; his feeding of the Five Thousand a dry run for the UN’s World Food Programme. They do not like to hear Theo’s message that it is better to buy a flat-screen TV made in China than sign a standing order for Christian Aid.

As they eat their lunch, Jomier tells Theo that when in Venice at Christmas he and Judith went to midnight Mass at St Mark’s Basilica. Theo listens but does not put any follow-up questions. He does not ask about Judith. Though he was happy to be a shoulder to cry on at the time of Jomier’s divorce, he prefers not to know about Jomier’s extra-marital amours. What was the position of Thomas Aquinas on sex with a post-menopausal woman? Is it the ontological equivalent of buggery or ejaculating into a condom? Jomier does not ask. He listens to Theo hold forth on Venice – a maritime empire built on trade – a prototype for the British Empire and, like the British Empire, brought down by its involvement in wars in its hinterland – for Britain Flanders, for Venice the Valley of the Po.

Jomier is used to Theo’s lack of curiosity about his private life. Or any other aspect of his life. Theo has no interest in people as such. His interests are on the one hand financial – markets, probabilities, risks – and on the other theological – eschatology, ethics, exegesis. He takes particular pleasure when the two combine. From the decline of Venice he moves on to the fissure between Latin and Orthodox Christianity that runs through the Balkans with Islamic enclaves left by the retreating Ottoman Turks – hence the different religious affiliations of Andro the Croatian (Catholic) and Bekim the Albanian (Muslim) – and ends over coffee with the hypothesis that thanks to idiotic altruism one or other would soon be out of a job.