William J. Bernstein on Crowd Behavior (Podcast)

Episode Summary

Executive Summary: In this episode of Masters in Business, Barry Ritholtz interviews William Bernstein, a neurologist turned financial theorist, about his book 'The Delusion of Crowds: Why People Go Mad in Groups.' They explore the psychology behind financial bubbles and religious manias, emphasizing how narratives, imitation, and status-seeking drive mass delusions. Bernstein draws parallels between historical bubbles like the South Sea Company and modern phenomena such as Bitcoin and QAnon, highlighting the role of social media as a vector for spreading delusions. The conversation also covers evolutionary psychology, cognitive biases, and practical investment advice.

Main Topics: Psychology of Mass Delusions (Priority: 5/5): Exploration of how narratives, imitation, and status-seeking drive financial bubbles and religious manias, with insights from neurology and evolutionary psychology. Role of Social Media (Priority: 4/5): Social media acts as a powerful vector for spreading delusions, accelerating the spread of manias compared to traditional media with built-in filters. Historical and Modern Bubbles (Priority: 4/5): Comparison of historical bubbles (South Sea, Mississippi Company) with modern ones (Bitcoin, Tesla, GameStop), emphasizing common patterns like easy credit and compelling narratives. Cognitive Biases in Investing (Priority: 4/5): Discussion of cognitive dissonance, confirmation bias, and the limbic system's role in financial decision-making, and how to overcome them. Evolutionary Adaptations (Priority: 3/5): How traits like imitation, pattern recognition, and status-seeking that were beneficial in ancestral environments become dysfunctional in modern financial contexts. Investment Advice and Life Cycle (Priority: 3/5): Bernstein advises balancing passion with practicality, and emphasizes that stock risk varies with life stage—stocks are safer for young savers and riskier for retirees.

Key Arguments: Mass delusions spread like pandemics: the agent is a compelling narrative, and the vector is the medium (e.g., social media). Human beings are cognitive misers who prefer mental shortcuts and compelling narratives over analytical rigor. The most compelling financial narrative is effortless riches; the most compelling religious narrative is apocalyptic end times. Imitation has enormous survival value in ancestral environments but leads to manias in modern contexts. Status-seeking, driven by sexual selection, underlies both financial and religious manias. Cognitive dissonance and confirmation bias cause people to double down on beliefs when confronted with contrary evidence. Easy credit is a key factor in bubbles, as seen in real estate cycles. Stocks are riskier for retirees due to sequence risk, but less risky for young savers who can buy during downturns.

Data Points: Percentage of 18th-century European stock issuance in a single year: 40% - Occurred in 1720 during the South Sea and Mississippi Company bubbles. Increase in fiber optic capacity without new fiber (2002-2015): 1,000-fold - Improvements in dry plant technology dramatically increased capacity. Followers of WallStreetBets: 10 million - Approximate number of followers on the Reddit forum, illustrating leaderless mobs. Time gold has been used as money: 2,000 years - Bernstein argues gold was not used as money until the Hellenistic period, contrary to gold bug claims of 5,000 years. Number of episodes in Greenleaf series: 65 - Bernstein recommends this series for entertainment during lockdown.

Pivotal Quotes: "Men, it has been said, think in herds, it will be seen that they go mad in herds, while they only recover their senses more slowly and one by one." — Charles Mackay (quoted by William Bernstein): Bernstein uses this quote to explain that manias spread socially, but recovery is an individual, solitary process. "There's nothing so disturbing to one's well-being and judgment as to see a friend get rich." — Charles Kindleberger (quoted by William Bernstein): Bernstein uses this to illustrate how envy and status-seeking drive participation in bubbles. "The best thing you can do is to meld those two things. You shouldn't take a job that you despise just to make money. But on the other hand, you shouldn't get a degree in ethnomusicology as well and expect to have a happy existence." — William Bernstein: Bernstein advises recent graduates to balance passion with practicality, avoiding extreme advice like 'follow your bliss' or purely money-driven careers.

Implications: Listeners should recognize that financial bubbles and mass delusions are driven by deep-seated psychological and evolutionary factors, not just irrationality. Social media amplifies these effects, making it crucial to cultivate critical thinking, diversify investments, and avoid herd behavior. Understanding cognitive biases can help investors make more rational decisions and avoid being swept up in manias.