Cattell: Personality Factors

Why Cattell’s Approach Was Different

Before Cattell, personality theories were often based on intuition or clinical observation. Cattell wanted a scientific, data-driven method. He believed that beneath all the surface differences in how people behave, there is a common structure of personality — and that this structure could be discovered by carefully measuring and analysing real data.

The Method: Factor Analysis

Cattell started with a huge list of descriptive adjectives from the English language — words like shy, outgoing, anxious, calm, stubborn, flexible. He then asked people to rate themselves on these traits. To make sense of the mass of data, he used a statistical technique called factor analysis.

Factor analysis groups together traits that tend to co-occur. For example, if people who describe themselves as “talkative” also tend to describe themselves as “sociable” and “energetic”, those three words might belong to one underlying factor. This factor is not directly visible — it is a latent or hidden dimension that explains why those surface behaviours hang together.

Source Traits vs. Surface Traits

Cattell made a crucial distinction:

• Surface traits are the obvious, observable clusters of behaviour — for example, being friendly, talkative, and cheerful all at once. These are the patterns you notice in everyday life.
• Source traits are the deeper, stable underlying factors that give rise to surface traits. They are the real building blocks of personality.

Cattell’s factor analysis revealed 16 primary or source traits. These are the fundamental dimensions along which every person can be placed.

The 16 Source Traits: Opposing Tendencies

Each source trait is described as a bipolar dimension — a continuum between two opposite tendencies. For example, one trait might range from reserved at one end to outgoing at the other. A person’s score falls somewhere along that line.

The 16PF Questionnaire

To measure these 16 source traits, Cattell developed the Sixteen Personality Factor Questionnaire (16PF). It is a self-report test that gives a profile of where a person stands on each of the 16 dimensions. …