How do we think about money?
What caused bankers to lose sight of the economy?
What caused individuals to take on mortgages that were not within their means?
What irrational forces guided our decisions?
And how can we recover from an economic crisis?

In this revised and expanded edition of the New York Times and Wall Street Journal bestseller Predictably Irrational, Duke University's behavioral economist Dan Ariely explores the hidden forces that shape our decisions, including some of the causes responsible for the current economic crisis. Bringing a much-needed dose of sophisticated psychological study to the realm of public policy, Ariely offers his own insights into the irrationalities of everyday life, the decisions that led us to the financial meltdown of 2008, and the general ways we get ourselves into trouble.

Blending common experiences and clever experiments with groundbreaking analysis, Ariely demonstrates how expectations, emotions, social norms, and other invisible, seemingly illogical forces skew our reasoning abilities. As he explains, our reliance on standard economic theory to design personal, national, and global policies may, in fact, be dangerous. The mistakes that we make as individuals and institutions are not random, and they can aggregate in the marketÂ-with devastating results. In light of our current economic crisis, the consequences of these systematic and predictable mistakes have never been clearer.

Packed with new studies and thought-provoking responses to readers' questions and comments, this revised and expanded edition of Predictably Irrational will change the way we interact with the worldÂ-from the small decisions we make in our own lives to the individual and collective choices that shape our economy.

Dan Ariely is the author of the New York Times bestseller Predictably Irrational. A professor of psychology and behavioral economics at Duke University, he lives in Durham, North Carolina, with his wife and two children.