The Drunkard's Walk

Why We Misunderstand Random Events

Human intuition is often poorly equipped to handle uncertainty and chance. We are naturally inclined to see order, purpose, and cause-and-effect relationships even when events are driven by pure randomness. This is famously illustrated by a man who won a lottery because he believed seven times seven equaled forty-eight. While this is a clear mathematical error, people constantly make similar, though more subtle, mistakes when processing information. Since the 1930s, researchers have noted that humans struggle to recognize or create truly random sequences. Brain imaging shows that the parts of our mind that assess risk and reward are closely linked to our emotional centers, such as the amygdala. In experiments where people must predict random sequences of colors, humans frequently try to find a hidden pattern, often performing worse than rats, who simply learn to bet on the most frequent color.

One of the most common ways we misread randomness is by failing to account for regression toward the mean. This principle states that in any series of random events, an extraordinary occurrence is likely to be followed by a more ordinary one. Psychologist Daniel Kahneman identified this while observing flight instructors who believed that screaming at students after a poor landing improved performance, while praising a good landing caused students to slack off. In reality, a student who performed exceptionally poorly was likely to improve regardless of the instructor's reaction, just as a student who performed exceptionally well was likely to return to their average level of skill the next time. We often mistake these natural fluctuations for the results of our own rewards or punishments.

These misunderstandings have significant consequences. In sports and business, success is often attributed solely to the skill of a coach or a CEO, leading to high-stakes hiring and firing decisions. However, data shows that replacing a leader often has no measurable impact on a team's performance, and high-profile executives frequently fail to replicate past successes at new companies. The same principles apply to publishing and film, where history is filled with examples of masterpieces like The Diary of Anne Frank and the Harry Potter series that were repeatedly rejected before becoming global phenomena. When a successful Hollywood executive like Sherry Lansing was ousted after a string of underperforming films, the industry blamed her "out-of-touch" tastes. However, the films she had already put in motion became massive hits the following year, suggesting her "failure" was merely a temporary dip in a random cycle. By learning to identify the footprints of chance, individuals can better navigate a world where random motion—much like the unpredictable path of a molecule—shapes careers, health outcomes, and daily experiences.