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The Japanese don’t sleep. This is what everyone – the Japanese above all – say. It’s not true, of course. But as a cultural and sociological statement, it is very interesting.

I first encountered these intriguing attitudes to sleep during my first stay in Japan in the late 1980s. At that time Japan was at the peak of what became known as the Bubble Economy, a phase of extraordinary speculative boom. Daily life was correspondingly hectic. People filled their schedules with work and leisure appointments, and had hardly any time to sleep. The lifestyle of this era is aptly summed up by a wildly popular advertising slogan of the time, extolling the benefits of an energy drink. “Can you battle through 24 hours? / Businessman! Businessman! Japanese businessman!”

Many voiced the complaint: “We Japanese are crazy to work so much!” But in these complaints one detected a sense of pride at being more diligent and therefore morally superior to the rest of humanity. Yet, at the same time, I observed countless people dozing on underground trains during my daily commute. Some even slept while standing up, and no one appeared to be at all surprised by this.