We don’t ask why God chose as his prophet a stutterer with a public speaking phobia. But we should. The book of Exodus is short on explication, but its stories suggest that introversion plays yin to the yang of extroversion; that the medium is not always the message; and that people followed Moses because his words were thoughtful, not because he spoke them well.

We know from myths and fairy tales that there are many different kinds of powers in this world. One child is given a light saber, another a wizard's education. The trick is not to amass all the different kinds of power, but to use well the kind you've been granted.

The pressure to entertain, to sell ourselves, and never to be visibly anxious keeps ratcheting up.

Every American was to become a performing self.

Whoever you are, bear in mind that appearance is not reality. Some people act like extroverts, but the effort costs them energy, authenticity, and even physical health. Others seem aloof or self-contained, but their inner landscapes are rich and full of drama. So the next time you see a person with a composed face and a soft voice, remember that inside her mind she might be solving an equation, composing a sonnet, designing a hat. She might, that is, be deploying the powers of quiet.

As a young boy, Charles Darwin made friends easily but preferred to spend his time taking long, solitary nature walks. (As an adult he was no different. “My dear Mr. Babbage,” he wrote to the famous mathematician who had invited him to a dinner party, “I am very much obliged to you for sending me cards for your parties, but I am afraid of accepting them, for I should meet some people there, to whom I have sworn by all the saints in Heaven, I never go out.”)

We put too much of a premium on presenting and not enough on substance and critical thinking.