trait | James Kennedy

Alerts you to society’s irrational love of extroverts.
352 pages, ★★★★

Introverts are singled out from a young age. They’re considered shy, socially-inept, boring, lazy and stupid in schools—at least, that’s the first thesis of this book.

The second thesis is that introverts are actually more valuable than people think. Evidence suggests that their moral reasoning, sense of responsibility, ability to stick to a plan, empathetic skills and thoughtfulness are better than those of extroverts. Introverts also earn more scholarships and graduate degrees than do extroverts.

Extroverts, on the other hand, make rash decisions, engage in risky behaviour (both in bed and on the stock market), are more prone to “groupthink”, make unsatisfactory team leaders and have poor listening skills. They have empty charisma—that is, they might appear to have everything in control, but when questioned, we realise they know nothing.

The third thesis, at the end of this book, says that “introvert” and “extrovert” are actually over-simplistic labels, and the book suggests “high-sensitive” and “low-sensitive” as more appropriate alternatives. Studies by Jerome Kagan have shown that people with sensitive amygdala prefer lower levels of stimulus—quiet rooms, fewer people, and familiar settings—characteristics of ‘introversion’. People with less-sensitive amygdala prefer higher levels of stimulus—loud places, more people, and new experiences—characteristics of ‘extroversion’. Different people need different amounts of stimulus to be comfortable, and these levels are quite fixed from birth through to adulthood.

Genes play an ambiguous role. I have C/C at the rs752306 SNP, which is located in the DRD4 dopamine receptor gene on chromosome 11. Even though the C allele has a frequency of as high as 75% (meaning most people have it), people still got excited when a study by Lee et al. in 2011 hinted at connections between rs752306 SNP and ‘schizophrenia’ and ‘risky behaviour’—traits which this book interprets as ‘extraversion’. Lee’s follow-up study showed no connection whatsoever. Personally, I think we understand so little about how genes affect our health that we should ignore any supposed ‘genetic factors’ for personality traits.

This book separates society along a single axis and looks for striking differences. The Geography of Thought did that too, along East/West lines, as did Men are from Mars, Women are from Venus, along gender lines. Take all these books with a pinch of salt. Society is not a dichotomy of extremes, but a melting pot in which most people are pretty close to ‘average’. Remember that you are, too. ★★★★