Truth & Character Thursdays

“Your character apprises the world with your actions and your personality surprises the world with your reactions” ― P.S. Jagadeesh Kumar

This is the second post in my “12 Things Everyone Should Know” series. You can access the full collection here.

Personality is one of the most perennially popular topics in psychology. It refers to patterns of thought, feelings, and behavior that are relatively stable over time, and which make each individual unique. Psychologists have made considerable progress in unravelling the mysteries of personality, including the extent to which it’s shaped by nature vs. nurture, how it contributes to our success and wellbeing, and how men and women differ in their personality profiles. In this post, I’ll explore 12 things everyone should know about personality. I hope you find it interesting and informative!

1. Hundreds of personality traits have been posited over the years, from sensation-seeking to self-esteem to self-efficacy. Most psychologists agree, however, that most personality variation can be captured with just a handful of higher-order traits.

The most popular approach posits five traits, often known as the Big 5. These are neuroticism, extraversion, openness, agreeableness, and conscientiousness. The figure below shows the sub-traits - or facets - that make up each of the Big 5 traits, at least according to one model.

2. Like basically all psychological traits, personality is partially heritable - in other words, differences between individuals in their personalities are due in part to differences in their genes.

Some of the best evidence for this comes from twin studies. The following figure shows the correlations for monozygotic (identical) and dizygotic (non-identical) twins for each of the Big 5 traits. As you can see, the correlations are stronger for the monozygotic twins, indicating that the traits are partially heritable.

How heritable are they? The table below shows a sample of heritability estimates for each of the Big 5 traits. The scale spans from 0 to 1, where 0 means a trait is 0% heritable and 1 means it’s 100% heritable. The exact numbers vary from study to study, but they all fall within a range suggesting a hefty contribution from both nature and nurture.

Note, by the way, that personality isn’t just heritable in humans; it’s heritable as well in other animals.

Truth & Character

What is one personality trait you recognized in yourself early in life that you have successfully learned to manage or channel in a positive way?