Now that you're an adult, you might still feel a pang of guilt when you decline a dinner invitation in favor of a good book. Or maybe you like to eat alone in restaurants and could do without the pitying looks from fellow diners. Or you're told that you're "in your head too much", a phrase that's often deployed against the quiet and cerebral. Or maybe there's another word for such people: thinkers.

There are only a few people out there who can completely overcome their fears, and they all live in Tibet.

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.

So stay true to your own nature. If you like to do things in a slow and steady way, don't let others make you feel as if you have to race. If you enjoy depth, don't force yourself to seek breadth. If you prefer single-tasking to multi-tasking, stick to your guns. Being relatively unmoved by rewards gives you the incalculable power to go your own way.

There is no one more courageous than the person who speaks with the courage of his convictions.

Solitude is one of our great superpowers... Solitude is the key to being able to make effective decisions and then having the courage of convictions to stand behind those decisions.

In the first study, Grant and his colleagues analyzed data from one of the five biggest pizza chains in the United States. They discovered that the weekly profits of the stores managed by extroverts were 16 percent higher than the profits of those led by introverts—but only when the employees were passive types who tended to do their job without exercising initiative. Introverted leaders had the exact opposite results. When they worked with employees who actively tried to improve work procedures, their stores outperformed those led by extroverts by more than 14 percent.