Women wearing trousers? All right, if they have to. Men giving up ties? It had to come, perhaps. But abandoning the knife and fork as eating utensils? Is nothing sacred?
Not according to research by Debenhams, which has identified a profound and shocking change in Britain's dining etiquette: people are giving up the knife and fork at table in favour of the fork on its own.
Forks now outsell matching knives by almost two to one across the country, the department store revealed yesterday.
Several hundred years after man triumphed over other ways of conveying food to mouth, such as fingertips, grasping hands, spoons or dagger points, the elegant cutlery combination of prongs and blade would appear to be on the way out - a victim of our addiction to takeaways and ready meals.
In its place, the American habit of using a single fork in one hand is gaining ever more ground, the figures suggest, because knives are not needed for the pre-cut pizzas, chips, burgers and pasta we increasingly consume.
Sales figures across Debenhams' 155 UK stores have revealed that large, main meal forks are outselling their matching knives by almost two to one.
London branches are leading the way, with customers in the capital buying almost three forks to every knife.
Restaurateurs also report that the trend is becoming visible in dining out.
"The knife will always be there, but people are definitely using fewer of them," said Hadi Aknin, the maitre d'hotel at the Launceston Place restaurant in Kensington, west London.
"Of course, if you have a steak you will need a steak knife, but many of the nouvelle cuisine-style dishes we do nowadays have so much preparation in the dish that there is less work for the diner. We see many customers eating with just the fork, although I always give them the option of the knife."
In a study by Debenhams, almost 32 per cent of customers said they bought fewer knives specifically because they now preferred using forks on their own.
An additional 24 per cent were baffled by place settings, while 28 per cent did not possess fish knives and saw no reason for buying them.
Nineteen per cent could not tell the difference between a soup spoon and a dessert spoon.
The retailer is launching a Civilised Dining Campaign to protect the traditional British way of eating (and promote itself in the process).
"Using both a knife and a fork to eat has held this country in good stead for centuries. It's one of the mainstays of being British," said its spokesman, Ed Watson.
"It's about maintaining standards, before the single fork habit becomes ingrained in the next generation. Bad table manners can turn an enjoyable meal into an embarrassment."
From next month, cadres of "advisers on dining etiquette" will be on hand at Debenhams stores to demonstrate impeccable manners and to demystify such complex problems as place settings.
An etiquette guide will be posted on its website.
"Many people still regard it as an essential life skill," Mr Watson added.
"It isn't that people no longer care about dining etiquette - they still do.
"Instead, the popularity of finger food and ready meals means many young people have never had to learn."