A polite notice taped to the front of a till in a busy café on a university campus: “We appreciate your phone call is very important to you, therefore we will not interrupt it to serve you until you have finished it.”

Epicureans know instinctively (because they are civilised and think of others), when not to make loud phone calls in public. I once had to endure, along with forty other people in the carriage, a cellphone conversation on a train, conducted in a piercing voice. After thirty minutes I could stand it no longer. In the Epicurean spirit of public service I confronted the woman and asked her to give us a rest. Actually, she did. Thinking is often what people do least well.