By the age of 3, children from wealthier households hear, on average, about 500,000 encouragements and 80,000 discouragements. The ratio is reversed in households on welfare.

In fact, the only way to remain creative over time--to not be undone by our expertise--is to experiment with ignorance, to stare at things we don't fully understand.

What you discover when you look at creativity from the perspective of the brain is that it is universal. We're all creative all of the time, we can't help but be creative.

The inconsistency of genius is a consistent theme of creativity.

The only way to maximize group creativity—to make the whole more than the sum of its parts—is to encourage a candid discussion of mistakes. In part, this is because the acceptance of error reduces cost. When you believe your flaws will be quickly corrected by the group, you're less worried about perfecting your contribution, which leads to a more candid conversation. We can only get it right when we talk about what we got wrong.

Cities force us to interact with strangers and with the strange. They pry the mind open. And that is why they are the idea that has unleashed so many of our new ideas.

We need to be willing to risk embarrassment, ask silly questions, surround ourselves with people who don't know what we're talking about. We need to leave behind the safety of our expertise.