Chapter 1 suggests that incentives affect almost every aspect of modern life, from how people behave when involved in online dating to why teachers cheat when offered significant bonuses. At the end of the chapter, Levitt and Dubner claim that businesses and individuals are most successful when they can determine appropriate incentives for their customers, fans, or students.

Conventional Wisdom

Levitt and Dubner dispel many ideas that are normally labeled “conventional wisdom.” Chapter 3 proves that someone willing to risk his life for a life of illegal, dangerous activity usually does not end up rich, and Chapter 5 demonstrates that a parent’s following the most current parenting trends and studies has little or no effect on a child’s academic success. Thus,

conventional wisdom is often shoddily formed and devilishly difficult to see through, though it can be done

by studying statistics objectively.

Cause and Effect

Dramatic effects, such as an unexpected widespread decrease in crime, often have buried, difficult-to-see causes. Levitt and Dubner use the legalization of abortion and the downfall of the Johnny Appleseed of Crack to explain the drop in crime rates in the 1990s and disprove the correlation between the crime drop and commonly viewed causes, such as the rise in police hiring or the use of innovative policing strategies. This theme also appears in the discussion of children’s names in Chapter 6.

Information Hoarding

From real-estate agents to the KKK, the amount and kind of information that an expert releases or hoards determines his or her power. If someone (i.e., Stetson Kennedy) or something (i.e., the Internet) takes control of and disseminates that information, the experts lose their advantage. Levitt and Dubner cite the downfall of the KKK and the falling prices of coffins and life-insurance premiums as examples of the power of access to information.