Charles Duhigg

There is a woman named Wendy Wood, who did a study when she was at Duke, and she followed around college students to try to figure out how much of their day was decision-making versus how much was habit. And what she found was that about 45 percent of all the behaviors that someone did in a day was habit.

As homeowners see the value of their homes decline, they become more likely to delay purchases of the big items - like automobiles, electronics and home appliances - that are ballasts of the American economy. When those purchases decline, large manufacturing firms, suddenly short on funds, could begin laying off employees.

At one point, I didn't get out of bed for, I think, three months, and I went down to the bottom of the hill one day and I had to call somebody to get me to come back up - come pick me up because I couldn't physically walk up the hill.