We’ve all done it: been overcome by a sudden sense of hard-upness at the moment when the collection plate comes round at the end of a cathedral service. We fumble in our pockets, feel a £1 coin and a £10 note, and decide that the £1 coin will do. This is a cathedral, for goodness sake, not a parish church: they must be rich, with all those gold-coloured vestments and choristers in ruffs.