500 years ago (circa 1500s), people generally followed a biphasic sleep pattern rather than one continuous eight-hour block. Known as “first” and “second” sleep, individuals typically went to bed shortly after dusk for 3–4 hours, woke around midnight for 1–2 hours for activities like reading or praying, and then took a “second sleep” until dawn.
Arguably from time immemorial to the nineteenth century, the dominant pattern of sleep in Western societies was biphasic, whereby most preindustrial households retired between 9 and 10pm, slept for 3 to 3 ½ hours during their “first sleep,” awakened after midnight for an hour or so, during which individuals did ...
Despite differences in their genetics, histories and environments, all three groups had similar sleep patterns. People in these groups slept slightly less than 6.5 hours a night on average. In comparison, people in industrial societies usually average seven to eight hours per night.
In the early modern era, first and second sleep had generally been of equal duration, approximately three to three and a half hours apiece. But a distinct imbalance began to emerge by the mid-1800s, marked by a gradual expansion of the first phase to five or six hours at the expense of the second.
Before the Industrial Revolution, people didn't always sleep straight through the night. Instead, they followed a pattern called “segmented sleep,” where they slept in two phases. They would go to bed for about 4 hours, then wake up for 1-2 hours in the middle of the night.
Humans need less sleep than our closest evolutionary relatives. However, we often sleep less than we need. Needing less sleep is a consequence of our ancestors' choices to remain awake longer — a behaviour that led to evolutionary benefits.
Leonardo da Vinci
He followed a polyphasic sleep pattern with a 20-minute nap every four hours. Given his expertise in so many things -- invention, painting, sculpting, architecture, science, music and more – the unconventional schedule must have worked for him.
First sleep and second sleep
This pattern was common in preindustrial societies, and it was most common to sleep early ("first sleep"), wake around midnight, and return to bed later ("second sleep"). Along with a nap in the day, it has been argued that this is the natural pattern of human sleep in long winter nights.
In Old Norse, a bed was referred to as a beðr, hvíla, rekkja or sæng. It is believed that breakfast took place around seven o'clock in the morning, when everyone was already on their feet; from some indirect notes from Family sagas, it seems that it was common to go to bed before midnight.
Tesla also only slept two hours per day but in an arcane manner. He said, “When I sleep, I sleep profoundly. To sleep deeply, profoundly, is an art like deep breathing that must be learned.
The 3-2-1 bedtime method is a sleep hygiene technique to improve rest by creating a wind-down routine: stop heavy 3 hours before bed (food, alcohol), stop mentally taxing activities/work 2 hours before, and turn off all 1-hour before sleep, reducing blue light and stimulating the brain for better sleep. It's often part of the broader 10-3-2-1-0 rule, which adds no caffeine 10 hours prior and no hitting snooze at the end.
Yes, 10 PM to 5 AM provides 7 hours of sleep, which falls within the recommended 7-9 hours for most adults, making it potentially enough, but it depends on individual needs; if you feel refreshed and function well, it's likely sufficient, but if you're tired, you might need more. Consistency, sleep quality (avoiding screens and caffeine), and listening to your body's signals (feeling energetic vs. needing an alarm) are key indicators of whether this schedule works for you.
He regularly indulged in brief daytime naps, occasionally more than once a day. These quick naps, lasting just a few minutes, were thought by Einstein to revitalize his mental energy and creative thinking. He felt that these short periods of rest gave him a renewed viewpoint to solve intricate scientific challenges.
Signs You're Not Getting Enough Core Sleep
Today, researchers are finding signs of REM sleep in a broader array of animals than ever before: in spiders, lizards, cuttlefish, zebrafish. The growing tally has some researchers wondering whether dreaming, a state once thought to be limited to human beings, is far more widespread than once thought.
Psychology Today reported that intelligent people are likely to be nocturnal beings, with those with a higher IQ going bed later on both weeknights and weekends.
God does not want His children to be anxious. He wants us to trust Him so much that we fall asleep peacefully every night. Perhaps sleep is intended by our Creator to be a continual reminder to trust Him and rest in Him.