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Day 1 — Sat, Mar 28

What even is an emotion?

Plato split the soul into three warring parts 2,400 years ago. Modern science still can't agree on a single definition — but Paul Ekman's cross-cultural experiments proved that at least some emotions are hardwired, not learned.

  • The word 'emotion' has no single accepted definition — like Louis Armstrong said about jazz: 'if you have to ask what it is, you'll never know'
  • Plato's tripartite model (Logos, Thumos, Epithumia) is surprisingly modern: reason governs, spirit enforces, appetite craves
  • Simon Baron-Cohen catalogued close to 1,000 emotion words across languages, collapsing them into 23 mutually exclusive categories
  • Paul Ekman's 1960s experiments with isolated tribes proved basic facial expressions are universal — not culturally learned
  • But culture still shapes expression: Japanese and Americans feel the same emotions watching films alone, yet Japanese suppress displays when others are present

Plato's Tripartite Soul

Three parts of the soul, each with its own desire and virtue — written ~380 BC in The Republic

Plato's Tripartite Soul Logos (Reason) Head — eternal truths, logic virtue: Wisdom governs Thumos (Spirit) Chest — ambition, pride, honour virtue: Courage enforces Epithumia (Appetite) Belly — hunger, craving, greed virtue: Temperance fights for reason well-ordered soul: reason leads, spirit enforces, appetite obeys
  • Logos (Reason) — the highest part, seated in the head. Deals in eternal forms and universal truths. Plato argued it should govern the other two parts entirely
  • Epithumia (Appetite) — the lowest part, seated in the belly. Drives evolutionary urges like hunger, but also includes greed and craving. Without check, it overwhelms the soul. Its virtue is Temperance: not eliminating desire, but keeping it in check
  • Thumos (Spirit) — seated in the chest. Not just anger — it's the complex set of ambition, pride, and hunger for recognition and honour. Connected to reason: when you eat junk food and feel ashamed, that's Thumos fighting Appetite on Reason's behalf. Its virtue is Courage
  • If trained properly, Thumos fights on Reason's side — this is Plato's model of the well-ordered soul

The Problem of Defining 'Emotion'

Why psychologists gave up on a single definition and started working with examples instead

  • The book notes that the word 'emotion' has no proper, agreed-upon meaning — even specialists can't pin it down
  • The Louis Armstrong analogy: emotion is like jazz. If you have to ask what it is, you'll never know. You recognise it when you feel it, but try defining it precisely and you fail
  • Modern psychologists and philosophers have given up on a single watertight definition. Instead, they define emotion by listing examples and clustering them
  • Simon Baron-Cohen (British psychologist) identified close to 1,000 emotion words and grouped them into 23 mutually exclusive categories
  • Paul Griffiths divides emotions into three groups: basic emotions, higher cognitive emotions, and culturally specific emotions

Nature vs Nurture: Ekman's Cross-Cultural Evidence

Are emotions universal biology or cultural software? A 1960s experiment in remote Papua New Guinea settled the debate — mostly

Ekman's Cross-Cultural Experiment (1960s) Photos Shown 😊 😢 😨 😠 🤢 😲 6 basic expressions shown to Papua New Guinea Remote tribe with zero Western contact no TV, no movies no cultural influence Result 100% matched correctly But: Cultural Display Rules Watching film WITH others JP: low US: high facial expression Watching film ALONE JP US identical expression
Key insight: the emotion is universal and biological, the display rules are cultural. You feel the same thing — you just learn when to show it.
  • A large camp of anthropologists believed emotions were entirely learned behaviour — culturally constructed, not biologically innate
  • This is a weak argument: there are literally different parts of the brain dedicated to recognising facial emotions. If emotions were purely learned, this neural hardware wouldn't exist
  • If emotions were culturally learned, we wouldn't share an emotional corpus across the world — but we do
  • Paul Ekman (one of the key scientists) tested this in the 1960s. He travelled to remote regions of Papua New Guinea where people had never seen Western media — no movies, no TV, no outside cultural influence
  • He showed them photographs of facial expressions (happy, sad, fearful, angry, disgusted, surprised) and asked them to match the emotion
  • They matched them perfectly — proving these basic expressions are hardwired, not learned from culture

Cultural Display Rules

Emotions may be universal, but the rules about showing them are not

  • The book acknowledges there is some truth in the 'learned' side — not the emotions themselves, but the rules about expressing them
  • Most 'emotional expression' depends on cultural norms. Japanese culture discourages open emotional display; American culture encourages it
  • A key experiment demonstrated this beautifully: Japanese and American participants watched emotionally triggering films (evoking sadness, joy, fear, anger)
  • When watched together with others present, Japanese participants showed little facial change compared to Americans — cultural suppression in action
  • But when they watched the same films alone, both groups showed the same facial expressions — identical emotional responses underneath
  • This is the critical distinction: the emotion is universal and biological, but the display rules are cultural. You feel the same thing; you just learn when to show it