There are other costs to employers. An elder-care facility in Sweden that tried a six-hour workday reportedly found that nurses took fewer sick days and were more productive. Fatigued workers cost employers $100 billion in lost productivity.

This all became obvious to the American business community long ago . As strong unions pushed for a 40-hour workweek in the 1800s, business leaders who acquiesced found that their companies became significantly more profitable and productive. In 1914, Henry Ford took the lessons of these natural experiments to heart and cut shifts in his plants to eight hours without reducing pay, leading to an output boom. By 1938, that 40-hour workweek was enshrined into law by the Fair Labor Standards Act, which requires time-and-a-half pay beyond that threshold.

The strength of the law has been whittled away over recent decades, however, to the point that millions fewer Americans are guaranteed extra pay for extra work than in 1979. That allows employers to push more employees to put in more hours essentially free. President Barack Obama proposed an update in 2016 that would have offered new or strengthened overtime protection to over 13 million workers; it was struck down by the courts, and President Trump’s version, proposed in March, will help 8.2 million fewer workers, thanks to a lower salary threshold and a failure to index it to inflation.

Business leaders seem to have forgotten the lessons they learned in the past: Humane schedules benefit employee and employer alike. China may have its 996 culture, but the United States doesn’t fare much better. Nearly a third of us put in 45 hours or more each week, while nearly 10 million clock 60 or more. The average European puts in between 7 percent and 19 percent less time on the job.

Policies like a strong overtime rule can help us return to a world where everyone does better by working less. Business leaders like Jack Ma have to get with the program, too. Glorifying those who sacrifice nearly all of their waking hours at the altar of work harms everyone, from the chief executive to the custodian.

Bryce Covert is a contributor at The Nation and a contributing opinion writer.

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