At the turn of the century we had 8 year-old boys getting hurt and killed working in underground mines seventy hour per week, 7 days. We had 8 year-old girls getting hurt and killed in garment factories....same work week.
Then, in 1911, there was the Triangle Shirtwaist Factory fire that claimed the lives of 146 girls. The mangled fire escape became the poster child in the campaign to enact labor laws:
First the New York State Legislature followed by Congress enacted sweeping labor law. Children were removed from the workforce. Ultimately, the work week was regulated to 40 hours. Minimum wage law was enacted.
Business, naturally, vigorously opposed any and all labor regulations predicting that if enacted, would lead to economic disaster. Labor law was enacted nevertheless, and the result was the most prosperous period in American economic history. First there was the Roaring Twenties. Then of course (as it did lately) Wall Street became ridiculously overactive leading to economic disaster. That disaster was repaired in large part through the enactment of additional labor regs.
A four-day work week would probably increase both consumption and productivity. Unless you ask Business who would, of course, predict the sky would fall.
