Podcast Summary: "Why You Wear Your Hair That Way & The Surprising Science of Human Stupidity"

Something You Should Know with Mike Carruthers
Date: September 4, 2025
Guests: Rachel Gibson (Hair Historian), Cesare Pietresic (Author & AI Expert)

Overview

This episode explores the intriguing history and psychology behind human hairstyles, from ancient times to the modern Instagram age, and delves into the surprising science and social dynamics of human stupidity in both everyday life and historical context. Host Mike Carruthers interviews hair historian Rachel Gibson for a fascinating tour through hair’s cultural legacy, before turning to Cesare Pietresic, author of Homo Idioticus, for an insightful dissection of why humans do—and keep doing—stupid things.

I. The Story and Psychology of Hair: Interview with Rachel Gibson

Why Do We Care About Our Hair?

• Hair as expression is universal and ancient, not merely vanity.
• Ancient recipes exist for hair dye and styling; concerns about gray hair and balding are timeless.
  Quote [08:20]:
  "The desire to transform our appearance is absolutely nothing new...the key concerns remain very similar to today, so namely covering gray hair and preventing balding." – Rachel Gibson

Hair Hygiene Through the Ages

• Clean hair was always a concern, though not always via washing—shaving and wigs were practical historic solutions.
• Ancient knit combs closely resemble those today.
  Quote [09:44]:
  "Even if people didn't have access to running water and shampoo...they were certainly concerned with keeping things out of their hair." – Rachel Gibson

Why Long/Short Hair?

• Long hair has historically signified health and fertility for women and men.
• The modern male preference for short hair owes much to Francis Russell abandoning wigs in 18th-century England to avoid a hair powder tax, sparking a fashion revolution.
  Quote [11:22]:
  "He stopped wearing a powdered wig and started being seen in polite society...with his natural, short, unstyled hair...He almost single-handedly changed the way that men in the West wore their hair forever." – Rachel Gibson

Fashion, Embarrassment, and Technology

• Past trends are easy to mock retrospectively.
• Today’s constant self-photography may reduce regrettable style choices and drives trends like the “llama cut” (curly on top) due to the way hair appears on screens.
• Pandemic lockdowns triggered a mullet revival, especially among Gen Z, who lack negative cultural associations with it.
  Quote [13:16]:
  "Technology influences hair all the time in terms of product development, but in terms of how a phone could change a hairstyle, I think that's really fascinating." – Rachel Gibson

The Mullet: Icon, Ridicule, and Revival

• The mullet’s practicality dates back to ancient warriors (short front, long back for combat).
• Rose to mainstream infamy in the 1980s–90s, then ridicule—yet now back in style without baggage for new generations.
• Quote [17:35]:
  "It's not pretty on a woman and it's not kind of considered handsome on a man. It's quite a strange haircut and it's a hybrid of long hair and short hair...people either love them or hate them." – Rachel Gibson

Hair Trends & Societal Change

• Popular, time-consuming styles historically tracked with privilege.
• The bob’s rise (1920s, 1960s) enabled liberated lifestyles; “wash and wear” by Vidal Sassoon marked a true shift.
  Quote [22:12]:
  "The time that people have to spend on their hair...really does dictate trends." – Rachel Gibson

Men’s Hair: Boring to Revolutionary

• Beatlemania in the 1960s radically changed expectations, with scandalously long hair.
• Punk movement (1970s) introduced bold color and spiky styles as acts of rebellion and self-expression.
• Quote [25:35]:
  "Punk is a great example of hair demonstrating status. It's a total rejection of societal expectations...creativity and this idea of being quite experimental and trying things." – Rachel Gibson

The Enduring Appeal of Blonde

• Dyeing and extreme methods to become blonde go back centuries (e.g., Renaissance Venetians bleaching with horse urine!).
• Blonde as a rare, prized color drives its desirability.
• Quote [27:14]:
  "Pure blonde hair is very rare. And scarcity always attracts people, and that's why people want to imitate it." – Rachel Gibson

Celebrity Influence and Iconic Hairstyles

• From Marie Antoinette to Veronica Lake to Jennifer Aniston (“the Rachel”), celebrities have driven mass hairstyle trends.
• Sometimes, what looks easy is actually high maintenance.
• Quote [30:22]:
  "That haircut is such a good example of the kind of your hair but better...The irony is her hair is naturally very thick and curly...She couldn't do it herself at home." – Rachel Gibson

II. The Surprising Science of Human Stupidity: Interview with Cesare Pietresic

Why Are Humans Stupid?

• Stupidity comes in layers: biology, psychological biases, heuristics, and poor institutional structures.
• Quote [35:19]:
  "The human stupidity has several layers of causation...biological, psychology...and how we structured our society and how we structured our institutions." – Cesare Pietresic

Everyday and Societal Stupidity

• San Francisco’s lenient crime policies encourage theft, demonstrating how conformity leads to “societal stupidity.”
• Russian vs. American submarines: the U.S. eliminated accidents via thorough procedure post-1960s; Russia did not, leading to fatalities—cultural tolerance of "minor" errors has real consequences.
• Quote [36:47]:
  "If you create all those rules, then obviously you will live in a place which is not safe." – Cesare Pietresic

Is It Culture or Stupidity?

• Feet binding in 1900s China as an example: past cultural “norms” can be harmful, but are often unchallenged until someone questions them.
• Semmelweis (handwashing pioneer) was ridiculed for suggesting cleanliness—shows resistance to evidence-based change is key element of stupidity.
• Quote [41:50]:
  "He saved so many lives. And you know what happened to him? He was fired and he died in poverty because his own environment...was making fun of him." – Cesare Pietresic

Modern Stupidity: Forms, Bureaucracy, and Tech

• Highlights everyday pointless bureaucratic rituals:
  • Signing for coffee with meaningless signature
  • ID checks for obvious adults
  • Airlines asking gender repeatedly
  • Government forms with irrelevant or bizarre questions (e.g., "Are you a terrorist?" or "Have you committed genocide?")
    Quote [44:16]:
    "If you go to Target…they will not sell it to you until you show them the passport or ID. Isn't it ridiculous?" – Cesare Pietresic

Are We Getting More Stupid?

• Yes: IQ scores in the Western world have declined since mid-1990s (Norwegian Army database, IBM research).
• Digital distractions and over-reliance on AI are linked to this trend.
• Quote [26:17]/[49:26]:
  "Since 1995 our IQ in the Western world is declining...Frequent messaging and being bombarded by texts alone is decreasing our IQ by 10 points." – Cesare Pietresic

What Can We Do About It?

• Everyday resignation perpetuates stupidity; challenging small, pointless rules matters (“drawing the line”).
• Historic examples (lead in gasoline/paint) show that small groups questioning orthodoxy can change society.
• Quote [51:31]:
  "You and I? Everyone? We need to draw the line. We need to in our everyday...evaluate if something makes sense." – Cesare Pietresic

III. Practical Intel: Stopping Rumination

[53:35]

• Rumination can lead to depression; distractions or walking in nature are proven strategies for relief.
• Stanford study: A nature walk (not urban) reduces rumination in a measurable way.

Notable Quotes & Memorable Moments

• “It is often tied to a bigger thing as well.” – Rachel Gibson [08:20]
• “There are so many examples of how it ties into religion, to life stages, to kind of ceremonial experiences...” – Rachel Gibson [08:20]
• "Francis Russell...almost single-handedly changed the way that men in the west...wore their hair forever." – Rachel Gibson [11:22]
• "We need to fight the stupidity every day in the small because if we don't, it becomes this behemoth of bureaucracy and state power..." – Cesare Pietresic [47:41]
• "There's research from IBM that frequent messaging...is decreasing our IQ by 10 points." – Cesare Pietresic [02:17]/[49:26]

Segment Timestamps

• [04:24 – 31:45]: The History & Psychology of Hairstyles (Rachel Gibson)
• [31:45 – 53:29]: The Science of Human Stupidity (Cesare Pietresic)
• [53:35 – 54:51]: Practical Intel: How to Stop Rumination

Conclusion

The episode brings to life the deep human urge to shape appearance—and society—exploring both hair’s symbolic pull across cultures, and the persistent, systemic, and sometimes hilarious examples of human folly, from individual everyday encounters to the inertia of entire civilizations. Listeners are left with the challenge to question—and resist—everyday stupidity, as well as new insights into why we might style our hair, or our thinking, the way we do.