The Confidence Code by Katty Kay, Claire Shipman

one’s ability to do something or succeed, and courage advocates for action with little regard for risk or success, springing from a very different place—a kind of moral center. Courage though, can be a critical partner to confidence, especially in situations where we are operating without the benefit of a confidence reserve, and we need to take those first, terrifying steps in order to start building it.
    And sure, other factors can limit us too. Lack of motivation might stop us from applying for that promotion. Procrastination could stop our training for that marathon. But if we assume the desire is there, the only real inhibitor is a lack of belief in our ability to succeed. And, let’s be honest, neither the beckoning of a comfortable couch nor a lack of motivation is likely to be what stops us from speaking out at confrontational moments or from cold-calling a potential client to pitch a sale. Confidence is all that matters there.
    A couple of questions had been nagging at us, though, since our intense conversations with Cameron Anderson about the merits of overconfidence. What is the optimum amount of confidence? Is that even knowable? With a clear definition of confidence in hand, this seemed easier to address. We had firm agreement from the social scientists and hard scientists on this one—a slight tilt toward overconfidence is optimal. Adam Kepecs, our rat expert, believes it’s fundamentally, biologically, useful. “It is adaptive to have appropriate levels of confidence so one makes the right bets in life,” he told us. “And, in fact, it is actually adaptive to have a little extra confidence for good measure in the face of uncertainty.” In other words—better to believe a bit too much in your capabilities than is called for, because then you lean toward doing things instead of just thinking about doing them.
    You probably have a good gut sense of your confidence level already, especially if you’ve recognized any of the behavior we’ve been describing. But there are formal measures. We’ve put two of the most trusted confidence scales in the notes at the end of the book. One was recently created by Richard Petty and his collaborator Kenneth DeMarree of the University of Buffalo. The other is a thirty-year-old survey still in heavy use. They don’t take long, if you want to put some numbers on your current state of assurance.
    Confidence, we believe, is our missing link. It’s what can propel us out of our overworked minds toward the liberating terrain of action. Confident action can take many forms—it is not always as overt as turning in a job application, or learning to skydive. A decision, a conversation, an opinion formed—those are all driven by confidence.
    Confidence, ultimately, is the characteristic that distinguishes those who imagine from those who do. It’s the stuff that seems to naturally inhabit the minds of the Susan B. Anthonys and the Malala Yousafzais. But we were also coming to see confidence as something we might all create. We recognized an encouraging power in the concept of confidence as action, which, when taken, sows and reaps more of the same. Action, we reasoned, is something we are all free to choose. Might it be that acquisition of confidence is basically our choice? Confirming that appealing notion required answering another question first.

3
    WIRED FOR CONFIDENCE
    The drive from Washington, DC, to western Maryland brought us to bucolic, red-barn country within an hour. Horses gazed up halfheartedly at our passing car, clearly oblivious to the great experiment going on just down the road. A tribe of three hundred rhesus monkeys, whose original members came from the mountains of Sri Lanka, has made its home in Poolesville. They’re here to help humans figure out why we behave the way we do.
    We’d come to see the monkeys, and also the man who has been watching them for more than forty years, neuropsychologist Steve Suomi of the National Institutes of Health