Quiet by Susan Cain

This post is a summary of a book I’ve read. When I summarise a book, I try to capture the intent of the author, rather than insert my personal opinion on their arguments. These notes are in no way an endorsement of the book or author. I frequently read books and authors I disagree with.

🔗 via app.thestorygraph.com.

Highlights

“Kagan devoted his career to studying the emotional and cognitive development of children … [he could predict] on the strength of a forty-five-minute evaluation, which babies were more likely to turn into introverts or extroverts”

“Many of the children turned out exactly as Kagan had expected”

“the high-reactive group—the lusty arm-pumpers—who were most likely to grow into quiet teenagers”

“high-reactive infants, the 20 percent who’d hollered at the mobiles bobbing above their heads, were more likely to have developed serious, careful personalities”

“Temperament refers to inborn, biologically based behavioral and emotional patterns that are observable in infancy and early childhood … personality is the complex brew that emerges after cultural influence and personal experience are thrown into the mix”

“The more reactive a child’s amygdala, the higher his heart rate is likely to be, the more widely dilated his eyes, the tighter his vocal cords, the more cortisol (a stress hormone) in his saliva—the more jangled he’s likely to feel when he confronts something new and stimulating”

Even psychological traits are the result of physical traits. People are apparently born with different levels of sensitivity in their senses, which leads to psychological differences. In a sense, it is all nurture, it’s just that we’re nurtured by our own physiology.

“high reactivity is associated with physical traits such as blue eyes, allergies, and hay fever, and that high-reactive men are more likely than others to have a thin body and narrow face”

“introversion and extroversion, like other major personality traits such as agreeableness and conscientiousness, are about 40 to 50 percent heritable”

“am I introverted because I inherited my parents’ high reactivity, copied their behaviors, or both”

“Conversely, high-reactive children may be more likely to develop into artists and writers and scientists and thinkers because their aversion to novelty causes them to spend time inside the familiar”

“about a quarter of Kagan’s high-reactive kids suffer from some degree of the condition known as “social anxiety disorder,” a chronic and disabling form of shyness”

“High-reactive kids who enjoy good parenting, child care, and a stable home environment tend to have fewer emotional problems and more social skills than their lower-reactive peers”

“High-reactive four-year-olds give more pro-social responses than other children when presented with moral dilemmas—but this difference remains at age five only if their mothers used gentle, not harsh, discipline”

“the footprint of a high- or low-reactive temperament never disappeared in adulthood”

“first set of data on a group of high-reactive children Kagan studied from four months of age—and sure enough, the amygdalae of those children, now grown up, had turned out to be more sensitive to the pictures of unfamiliar faces than did the amygdalae of those who’d been bold toddlers”

“Schwartz’s research suggests something important: we can stretch our personalities, but only up to a point”

“If you were a high-reactive baby, then your amygdala may, for the rest of your life, go a bit wild every time you introduce yourself to a stranger at a cocktail party”

“Once you understand introversion and extroversion as preferences for certain levels of stimulation, you can begin consciously trying to situate yourself in environments favorable to your own personality”

“can organize your life in terms of what personality psychologists call “optimal levels of arousal” and what I call “sweet spots,” and by doing so feel more energetic and alive than before.”

“some people are aggressive with peers and subordinates but docile with authority figures; others are just the opposite. People who are “rejection-sensitive” are warm and loving when they feel secure, hostile and controlling when they feel rejected”

“introverts are capable of acting like extroverts for the sake of work they consider important, people they love, or anything they value highly”

“we’re involved in core personal projects that we consider meaningful, manageable, and not unduly stressful, and that are supported by others”

“we are only pretending to be extroverts, and yes, such inauthenticity can be morally ambiguous (not to mention exhausting), but if it’s in the service of love or a professional calling, then we’re doing just as Shakespeare advised”

Some attributes of your body, and therefore mind, more or less malleable than others. When it comes to physical attributes, it’s pretty obvious which attributes you have a high-degree of control over. You can make yourself stronger, but you cannot make yourself taller. When it comes to your personality, taste, attitudes, and mental health, it’s much more difficult to discern.

This book explores temperament, the idea of innate personal attributes, and how temperament impacts emotions and behaviour. Specifically, this book focuses on introversion and extroversion, and the degree to which these attributes are predetermined as a result of temperament.

The claim: temperament, which is innate, has a strong relationship with introversion/extroversion. While it’s possible for introverts to behave like extroverts in certain circumstances, it’s generally not a good idea for introverts to force themselves into an extrovert lifestyle.

This is a good book for any introvert obsessed with self-improvement, who might be causing themselves unnecessary suffering over-optimising aspects of their personality that are relatively unmovable.

Interesting idea to dig into: situationism and the “person-situation” debate.

Find the book here.

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