Why can a 50p aspirin do what a 5p aspirin can't? If an item is "free" it must be a bargain, right? Why is everything relative, even when it shouldn't be? How do our expectations influence our actual opinions and decisions? In this astounding book, behavioural economist Dan Ariely cuts to the heart of our strange behaviour, demonstrating how irrationality often supplants rational thought and that the reason for this is embedded in the very structure of our minds. Predictably Irrational brilliantly blends everyday experiences with a series of illuminating and often surprising experiments, that will change your understanding of human behaviour. And, by recognising these patterns, Ariely shows that we can make better decisions in business, in matters of collective welfare, and in our everyday lives from drinking coffee to losing weight, buying a car to choosing a romantic partner.About the Author Dan Ariely is the Alfred P. Sloan Professor of Behavioral Economics at MIT. His work has been featured in leading scholarly journals as well as a variety of popular media outlets, including the New York Times, Wall Street Journal, Washington Post, Boston Globe, Business 2.0, Scientific American, and Science. He has also been featured on CNN and National Public Radio. Dan publishes widely in the leading scholarly journals in economics, psychology, and business. His work has been featured in a variety of media including The New York Times, Wall Street Journal, Washington Post, Boston Globe, Business 2.0, Scientific American, Science and CNN. He splits his time between Princeton, NJ, and Cambridge, MA.