It is not a valid reason, but it is an effective reason. It may not be right, but it is real, and one ought to have strategies in place to ameliorate this phenomenon. Extroverts cannot understand why you don&#x27;t want to talk.<p>As an extreme introvert myself, I have become used to being accused of rudeness, snobbery, hostility and general weirdness. Strangers and acquaintances become appreciably tense if I dare to produce a book, or abstract myself in thought.<p>The trick is to set such people at ease. Show goodwill, talk about the weather for fifteen seconds max, and then switch off. The irony is that if Guido Menzo had taken the trouble to explain what he was writing, with the appropriate nerdish enthusiasm, he would have been guaranteed to be left alone for the rest of the flight.