Seth Stephens-Davidowitz opens by presenting internet search data as a uniquely valuable data source for understanding genuine human thought and behavior, since people search privately for things they wouldn't admit in surveys or public statements.

Why search data offers this unique value:

• Traditional surveys and self-reported data are subject to significant social desirability bias, where people report what seems socially acceptable rather than their genuine thoughts or behaviors
• Private search behavior, conducted without social observation, tends to reveal more genuine underlying attitudes, curiosities, and concerns
• Stephens-Davidowitz's specific research, drawing on this data source, reveals numerous surprising gaps between publicly stated attitudes and privately searched behavior

This opening establishes the book's distinctive data source and its central methodological argument for why this data reveals genuine human behavior more accurately than traditional self-reported measures.