Habits, scientists say, emerge because the brain is constantly looking for ways to save effort.

The problem is that your brain can't tell the difference between bad and good habits, and so if you have a bad one, it's always lurking there, waiting for the right cues and rewards.

However, to modify a habit, you must decide to change it. You must consiously accept the hard work of identifying the cues and rewards that drive the habits' routines, and find alternatives. You must know you have control and be self-conscious enough to use it -- and every chapter in this book is devoted to illustrating a different aspect of why that control is real.

Companies aren’t families. They’re battlefields in a civil war.

Most of the choices we make each day may feel like the products of well-considered decision making, but they’re not. They’re habits.

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.

Between calculated risk and reckless decision-making lies the dividing line between profit and loss.