Predictably Irrational: The Hidden Forces That Shape our Decisions

Predictably Irrational opens with two experiences that inspired the author, Dan Ariely, to spend his entire career studying human behavior. The first experience occurred when Ariely was 18 years old: A horrific accident left 70% of his body covered with third-degree burns. Ariely spent the next three years “wrapped in bandages in a hospital” (xiii) or in a tight synthetic suit and mask during rare public outings, which he likens to a “crooked version” (xiii) of Spider Man’s suit. During these three years, Ariely couldn’t participate in normal daily activities, making him feel socially alienated. He began observing these activities from an outside perspective as if he were from another culture or planet.

The second experience was a college class on brain physiology. Ariely routinely proposed alternate interpretations and rival hypotheses in this class, and rather than being dismissive, the professor encouraged Ariely to pursue empirically testing his ideas. For example, Ariely spent three months implanting catheters in the spinal cords of several dozen rats. He then gave them different substances to test how a certain stage of epilepsy developed. While his hypothesis turned out to be invalid, he realized “that science provides the tools and opportunities to examine anything I found interesting” (xvi), which set him on his path to empirically studying what makes humans tick.