8-hour sleep is not natural - it was forced on workers

 

Biphasic sleep and the lost nighttime interval: from Thomas Wehr's experiment to modern life.

The 8-hour sleep has not always existed but is rather a modern invention of the industrialized world that needed efficient and docile 14-hour-a-day workers.

Before the introduction of night lighting, people slept in two stages - one from 9/10 pm to around 1 am and a second after 2-3 am. Between the two there was a period of wakefulness that people used for prayer, for writing (poets and writers of the time), for work, for visiting relatives. It was a period of calm and relaxation, during which the level of calm hormones was doubled. We have lost that state of peace and tranquility and perhaps it is time to recover it.

The experiment carried out by Thomas Wehr is one of the most famous studies on **biphasic sleep** (or "biphasic sleep").

In the 1990s, Wehr wanted to understand how people slept before the advent of artificial lighting. So he created an experiment in which participants were kept in a controlled environment, without artificial light, for several weeks.

What he did, exactly:

The participants were exposed to 14 hours of darkness per day (much more than in modern life).

The rest of the time, they had normal light.

They had no access to phones, TVs, or other sources of stimulation.

What he observed:

After a few weeks, the participants’ sleep patterns naturally changed:

1. They slept for about 4 hours (the first nap)

2. They woke up and sat quietly for 1–2 hours (without anxiety)

3. Then they slept again for another 4 hours (the second nap)

This pattern is called biphasic sleep.

Key takeaways:

Waking up during the night isn’t necessarily a problem — it can be **natural**.

In the past, people probably had a “first sleep” and a “second sleep.”

The waking hours in between were often used for reflection, prayer, or quiet activities.

Why it matters today:

Many people worry about waking up at night, but the study suggests that this may be a **biological legacy**, not a disorder. The problems are mostly due to modern lifestyles and sleep-related stress.

That state between the two sleeps — observed in Thomas Wehr’s experiment — is often described as a natural form of “spontaneous meditation.” It’s not exactly meditation in the modern sense (as a learned technique), but it shares many similar characteristics.

What this state feels like:

After the first nap (~3–4 hours), the body is partially rested, and the mind enters a special state:

• you are awake, but very relaxed
• thoughts are slower and more fluid
• a feeling of calm clarity appears
• time seems to flow differently (slower)

Many study participants said they did not feel the need to be distracted – they simply sat still.

What happens in the brain during this period:

• melatonin levels are still high (which is why you feel calm)
• brain activity may resemble alpha or theta wave states, associated with meditation and light dreaming
• you are not fully “alert” mode, but not in deep sleep either

It is a kind of transition zone between the conscious and subconscious.

This state has effects similar to meditation:

• reduces stress
• favors introspection
• can lead to creative ideas or revelations
• emotions are more “settled”

In the past, people used this time for:

• prayer
• reflection
• writing or thinking
• sometimes even quiet conversations

Why we don’t experience it anymore today:

In modern life:

• artificial light shortens the period of darkness
• compressed schedule forces continuous sleep
• if you wake up at night, anxiety appears (“I should be sleeping!”)

This anxiety breaks the very calm state that would naturally occur.

If you wake up at night and can’t fall asleep right away:

• don’t panic
• avoid your phone or bright lights
• stay calm, breathe slowly
• let your thoughts flow without controlling them

It can become one of the most peaceful and clear moments of the day.

Industrialization changed the environment and social rules in such a way that the natural model became impractical.

1. Artificial lighting compressed the night

With the advent of street and household lighting (gas, then electricity), people were no longer dependent on sunset. The day was artificially “lengthened”:

• you went to bed later
• you had fewer hours of continuous darkness
• the body no longer easily fit into the “first sleep + break + second sleep” structure

In Thomas Wehr’s experiment, the key was precisely exposure to **prolonged darkness** — a rare thing today.

2. Fixed work schedule

Industrialization brought:

• rigid work shifts (e.g. 8:00–17:00)
• strict punctuality
• need to be alert early in the morning

Biphasic sleep includes a period of wakefulness at night. This becomes problematic if you need to:

• wake up early
• function at full capacity

So people started to "condense" their sleep into a single block.

3. Changing cultural values

In the past, waking up at night was normal. After the industrialization:

• the idea of ​​“8 hours of continuous sleep” emerged
• waking up at night was associated with insomnia
• efficiency and productivity became a priority

Thus, a natural pattern was reinterpreted as a problem.

4. Constant stimulation and technology

Even after work:

• bright light
• screens
• intense mental activity

These:

• delay sleep
• reduce its depth
• eliminate the “space” between the two phases

5. Social pressure and sleep anxiety

If you wake up at 2–3 am today, the typical thought is:

“I have to fall asleep right away or I’ll be done tomorrow.”

This pressure:

• increases cortisol (the stress hormone)
• destroys the natural calm, meditative state
• prevents the return to a biphasic rhythm

The key point

Biphasic sleep probably hasn't gone away — it's just been **suppressed by the environment and social norms**. The human body can still enter this pattern if conditions (especially prolonged darkness and lack of pressure) allow it.