HAROLD MACMILLAN, a patrician British prime minister who came to power in the 1950s, famously asked who are the middle classes. Had he looked down his nose carefully enough he would have seen them all around him. By the 1960s they comprised just under a third of the world's population. Nowadays the chance that you are a member yourself is high—57% of the globe count as middle class, according to Surjit Bhalla, an Indian economist. This has much to do with impressive economic growth in developing countries. China's middle class has expanded particularly rapidly. Now the bulk of the population of the Middle kingdom are middle class.

EPA