In 1937, a social experiment was launched in the UK — Mass-Observation. The new organisation wanted to find out about everyday life and attitudes in Britain by recruiting teams of volunteers to fill in questionnaires and write down what people were saying about issues of the day. These observers would keep diaries to record people’s chat in just about every public situation: at work, church, football terraces, on the street, even down the pub. The scribblers could be anywhere and everywhere.

It seems strange to us to imagine a time when there was so little information about the views of ordinary people that it had to be gleaned by eavesdropping. But if Mass-Observation sounds a touch intrusive, which it does, it was mild compared with