This week, someone has started handing out badges on the tube. These badges – white, bearing a London Underground logo and the two words “Tube Chat?” – are intended to inform other travellers that the wearer would, no honestly, really, genuinely welcome being engaged in conversation by total strangers.

You’re probably already thinking, “Hmm, that doesn’t sound very London to me.” And you’d be right: it doesn’t. Despite that logo, a colour bar that replicates the tube line colour schemes and the same font used for the Underground, this is absolutely not an official Transport for London (TfL) campaign. It’s the work of someone called Jonathan Dunne, who tweets excitedly about his creation as @tube_chat.

Dunne, whose project is founded on the idea that “everyone could do with a daily chat”, yesterday told the BBC that handing out the badges had been unexpectedly “difficult” and that he had anticipated it being “way more fun” than it has been. “Twenty percent [of commuters] think it’s nice and about 80 per cent of people think it’s terrible, worst idea ever.”

If you glance at Twitter, though, you’ll find that approximation was, if anything, over-optimistic. And by Thursday lunchtime Labour London Assembly member Tom Copley was joking that this “abomination” would require investigation at Mayor’s Question Time.

There may, joking apart, be IP issues surrounding logo usage that TfL could choose to invoke should the project trouble it. And it may have cause. The official-seeming badge could easily distract from TfL’s more seriously-intentioned and authorised badges: the longstanding “Baby on Board” one for expectant mothers, and the new badge for people who may have difficulty standing, but whose disadvantages are not immediately apparent to the observer, launched two weeks ago by Mayor Sadiq Khan.

So, why does everyone hate the idea so much? And how did Tube Chat’s creator not see it coming? I have a theory. A Politeness Theory, in fact.

Politeness Theory is a branch of Semiotics that has existed for a few decades. Simplifying hugely (it’s a big field), Politeness Theory holds that there are “positive politeness” cultures typified by casual, but often ritualised, intervention (“Hey! How are you?”/”Salaam”/”Ayubowan”), the ignoring of which is considered rude. But there are also “negative politeness” cultures, where the thing that’s considered rude is intervention in another’s “personal space” without strong cause.

Japan has a negative politeness culture, of which its primary language’s complex set of spoken honorifics is often taken to be a strong example. Japanese cities, moreover, have an even more overt negative politeness culture. The ritualised nature of Japanese politeness is rendered impossible to apply equitably by the sheer scale of a city like Tokyo, making it more polite to acknowledge no one, rather than risk offence by acknowledging some and not others – which would be construed as ruder than ignoring all.

London is like that. In London, not acknowledging others without cause is a form of politeness, not rudeness, occasioned by the sheer number of people.

To mistake London’s negative politeness for rudeness is a common error, one made not only by people from countries with a positive politeness culture, but even people from the rest of this country. (The UK as a whole is judged to have a negative politeness culture, albeit one not as paradoxically overt as London’s or Japan’s.) After all, we’ve all seen people delightedly greet close friends on the tube once that protective negative politeness bubble is punctured. That bubble is not rude, or even unfriendly; it’s a contextually appropriate form of being polite.

Jonathan Dunne is American: from a country with a classic positive politeness culture (mocked by even non-London Britishers as the “Have a nice day!” culture). Dunne has well-meaningly blundered into a classic culture clash between the two countries that are, as the cliché goes, divided by a common language, mistaking an alien politeness for a familiar rudeness.

Tellingly, the first example of negative politeness speech in Penelope Brown and Stephen Levinson’s Politeness: Some universals in language usage (1971/87), a sort of magnus opus of Politeness Theory, is “Would you know where Oxford Street is?”

Of course it is. Of course it is.

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