[sgt101]

>Society demands a sleep schedule, yet the very idea of sleeping on a schedule is newly invented for industrial society.

Umm--- pre-industrial society everything stopped when it went dark. Humans have very poor night vision, we can't function in the dark and so basically everyone went to sleep when the sun went down.

[forgotmypw16]

That's not true, people used to wake up for several hours a night. There were also those up through the night tending fire and looking for predators. And darkness does not rule out sleeping during the day.

https://www.sciencealert.com/humans-used-to-sleep-in-two-shi...