you once said to would like to sit beside me while I write. Listen in that case I could not write at all. For writing means revealing one self to excess; that utmost of self-revelation and surrender, in which a human being, when involved with others, would feel he was losing himself, and from which, therefore, he will always shrink as long as he is in his right mind...That is why one can never be alone enough when one writes, why there can never be enough silence around one when one writes, why even night is not night enough.

Schwartz's research suggests something important: we can stretch our personalities, but only up to a point. Our inborn temperaments influence us, regardless of the lives we lead. A sizeable part of who we are is ordained by our genes, by our brains, by our nervous systems. And yet the elasticity that Schwartz found in some of the high-reactive teens also suggests the converse: we have free will and can use it to shape our personalities.

In our culture, snails are not considered valiant animals - we are constantly exhorting people to "come out of their shells" - but there's a lot to be said for taking your home with you wherever you go.

...I also believe that introversion is my greatest strength. I have such a strong inner life that I’m never bored and only occasionally lonely. No matter what mayhem is happening around me, I know I can always turn inward.

Any time people come together in a meeting, we're not necessarily getting the best ideas; we're just getting the ideas of the best talkers.

I actually find extroversion to be a really appealing personality style.

Indeed, your biggest challenge may be to fully harness your strengths. You may be so busy trying to appear like a zestful, reward-sensitive extrovert that you undervalue your own talents, or feel underestimated by those around you. But when you’re focused on a project that you care about, you probably find that your energy is boundless.