Oh dear, has it come to this? I have been barred entry to my club. The stern finger of a porter pointed unpityingly towards the double doors, and pausing only to collect the guest who was waiting for me upstairs I slunk out.

I was wearing a tie the club tie, as it happens although the Garrick, in a bid to attract a more arty crowd, has waived the rule requiring one at lunchtime. It was my trousers that offended. They were jeans. Now, jeans are hardly a new phenomenon.

On a visit to Genoa recently, I saw some 16th-century denim. Admittedly, it was in the Museo Diocesano and painted with the Passion of Christ. Genoa, called Genes in French, is supposedly where jeans originated.

The blue cloth was worn by dockers, before finding its way to the US (possibly on Christopher Columbus’s caravel as he was Genovese). I had thought that in the course of the 20th century it had become a sartorial universal, a trouser that transcended age and class. Not in Clubland. I shan’t imitate a friend who, on being told he couldn’t remove his jacket in a nightclub, took off his trousers instead. But I’ll consult the rule book. I suspect pyjamas aren’t specifically forbidden. Next time, I’ll go in them.