Why Did Ancient Humans Sleep Twice a Night?

It's 3:12 in the morning and you are extremely awake. You check the phone. You do the maths. Four hours and eighteen minutes, if you fall asleep right now. And now you're not just awake — you're awake and failing. Except for most of recorded history, waking in the middle of the night wasn't a problem. It was so ordinary it had a name. Two names. What came before was your first sleep. What came after was your second. We have this written down more than five hundred times — in diaries, court depositions, medical manuals, and prayer books printed specifically for the hour between them. Then it vanishes. And the number that replaced it didn't come from a doctor. 00:00 The 3AM maths 01:52 Five hundred times 04:19 The dark room 06:52 Who took it 09:22 What the appointment was for SOURCES Ekirch, A. R. (2001) — "Sleep We Have Lost", American Historical Review Ekirch, A. R. (2005) — At Day's Close: Night in Times Past Wehr, T. A. (1992) — biphasic sleep under short photoperiods, Journal of Sleep Research Thompson, E. P. (1967) — "Time, Work-Discipline, and Industrial Capitalism" Robert Owen, c.1817 — the eight-hour day proposal #sleep #history #insomnia