Why do British people only like to talk about the weather and not about people and things around them?
Inviolable personal castle: the British pay special attention to respecting everyone's own "personal world" (the British call it "PR-Pr-ivacy"). This is a word formed by a long-term national habit, which has a very rich meaning and is often mentioned by the British. For example, it's best to live in an independent house far from the city center. If there are neighbors, fences should be used to separate them, and windows should be covered with green trees, so that the daily life and social interaction of people in the room are not known to outsiders. It is very impolite to push the door between neighbors and visit people you know without permission, which is an interference to others' lives. Even if you call someone without any justifiable reason or at an appropriate time, it will interfere with others' "personal world".
A taciturn Englishman: The Englishman is not only afraid of others intruding into his life, but everything they don't want to tell, even if it's not personal, belongs to his "personal world" and doesn't want others to inquire. For example, what he does at home, who he associates with, what his family relationship is, how much he earns, which party he belongs to, who he votes for in the election, what he even eats, and whether he likes drinking or not ... These are not questions that ordinary beginners should ask. If you ask, it is impolite or boring. Because of this, the British will not talk to strangers easily without being introduced.
However, the British silence is not out of arrogance, nor is it just for fear that others will disturb their thinking, but more out of respect for others and fear of disturbing their silence. If a foreigner says "I'm sorry", he can still break this thin ice and have a friendly conversation first. However, it is an exception on the subway. The subway is an occasion for British people to read newspapers while walking, which has been a habit for many years.