Steven Levitt and Stephen Dubner open by demonstrating how careful economic analysis of incentives can explain surprising, seemingly unrelated everyday behaviors and social phenomena, applying economic reasoning tools well beyond traditional economic subject matter.

Why this expanded application of economic reasoning proves so compelling:

• Economic analysis tools — particularly careful attention to underlying incentive structures — apply usefully to diverse phenomena not traditionally considered 'economic' subject matter
• The authors' specific examples demonstrate how seemingly irrational or mysterious behavior often reflects entirely rational responses to underlying incentive structures, once properly analyzed
• This opening establishes the book's broader methodological approach: applying rigorous economic reasoning to diverse everyday phenomena, producing genuinely surprising insights

This opening establishes the book's distinctive methodological approach, applying economic analysis tools to unconventional, everyday subject matter beyond traditional economic topics.