Once you understand that habits can change, you have the freedom and the responsibility to remake them. Once you understand that habits can be rebuilt, the power of habit becomes easier to grasp and the only option left is to get to work.

Typically, people who exercise start eating better and becoming more productive at work. They smoke less and show more patience with colleagues and family. They use their credit cards less frequently and say they feel less stressed. It's not completely clear why. But for many people, exercise is a keystone habit that triggers widespread change.

As people strengthened their willpower muscles in one part of their lives—in the gym, or a money management program—that strength spilled over into what they ate or how hard they worked. Once willpower became stronger, it touched everything.

Shampoo doesn’t have to foam, but we add foaming chemicals because people expect it each time they wash their hair. Same thing with laundry detergent. And toothpaste—now every company adds sodium laureth sulfate to make toothpaste foam more. There’s no cleaning benefit, but people feel better when there’s a bunch of suds around their mouth. Once the customer starts expecting that foam, the habit starts growing.

Hiding what you know is sometimes as important as knowing it.

Since the 17th century, insurance agents have been the foremost experts on risk.

Belief is easier when it occurs within a community.