The Majority, a new show at London’s National Theatre by the performer and playwright Rob Drummond, is inspired by a wave of recent electoral upsets, from the Scottish independence referendum in 2014 to the Brexit vote last year. Throughout the show, Drummond asks a series of timely questions to which the audience votes “yes” or “no” on in real time, with the results immediately revealed, as he demonstrates how easily the shape of a question can alter its answer.