Trait Theory and Personality Dimensions

Trait theorists view personality as a collection of characteristic ways of behaving.
Gordon Allport identified approximately $4,500$ English words describing traits and categorized them into three levels:
- Cardinal traits: Dominate an entire personality and are rare (e.g., Ebenezer Scrooge’s greed or Mother Theresa’s altruism).
- Central traits: Core characteristics that build our basic personalities (e.g., kindness or agreeableness).
- Secondary traits: Preferences or attitudes that appear only under specific circumstances (e.g., feeling nervous before a speech).

Raymond Cattell reduced the trait list to $171$ and eventually identified $16$ primary dimensions of personality.
He emphasized that traits are not simply present or absent; instead, everyone possesses the same traits to varying degrees.
The $16\text{PF}$ (Personality Factors) questionnaire measures these dimensions on a continuum, such as warmth (reserved vs. supportive) or emotional stability (moody vs. calm).

The Eysencks focused on temperament, believing personality is largely governed by biology and genetic inheritance.
They initially proposed two dimensions:
- Extroversion/Introversion: Sociability and the need for interaction versus a preference for solitude.
- Neuroticism/Stability: Emotional sensitivity and the activity of the sympathetic nervous system.
Later, they added a third dimension: Psychoticism versus Superego Control (independence/hostility vs. altruism/cooperation).
Their theory is often mapped onto the four Greek temperaments: melancholic, choleric, phlegmatic, and sanguine.

This is the most widely accepted theory in contemporary personality psychology, using the mnemonic OCEAN:
- Openness to experience: Curiosity and range of interests.
- Conscientiousness: Goal-directed behavior and dependability; positively correlated with academic success.
- Extroversion: Sociability and emotional expression.
- Agreeableness: Levels of cooperation and trustworthiness.
- Neuroticism: Tendency toward emotional instability and negative emotions.
Stability: Traits are relatively stable across the lifespan, though conscientiousness and agreeableness tend to increase with age, while neuroticism and extroversion decline slightly.