The human mind has a natural inclination to find patterns and causal relationships in the world around us. However, this propensity often leads us astray, blurring the lines between cause and effect. In this article, we explore the concept of false causality through intriguing examples that demonstrate how our perceptions can be distorted. By understanding the pitfalls of attributing causality incorrectly, we can approach information with a more discerning eye and avoid drawing erroneous conclusions.

The Lice and Fever Conundrum

The belief in the Hebrides that head lice were responsible for illness demonstrates how false causality can persist in society. According to this belief, the lice in their hair would vanish when someone in the community became ill with a fever. The villagers, observing this pattern, reasoned that the lice themselves were the cause of the illness. They would intentionally put lice back in the patient’s hair to cure the sickness, thinking this would help restore their health. Once the lice returned, the patient would show signs of improvement.

However, this understanding of cause and effect was deeply flawed. In reality, the lice weren’t causing the fever, but rather, the fever caused the lice to flee. Lice are parasites that thrive in cooler environments, and when a person develops a fever, the rise in body temperature makes it unbearable for the lice to remain. They would leave the host to seek cooler surroundings. The lice would return once the fever subsided and the body temperature normalized. In this case, the correlation between lice leaving and the improvement in the patient’s condition was purely coincidental. The true cause of recovery was the body’s natural ability to combat the fever, not the return of the lice.

This misunderstanding of causality could have serious implications, especially when it leads to unnecessary or ineffective treatments. The villagers mistook a simple biological response as a healing intervention, which highlights how easy it is to attribute cause to something based on perceived patterns rather than actual mechanisms.

Firefighters and Fire Damage: A Misleading Correlation

The example of firefighters being associated with greater fire damage in one city clearly illustrates how correlation is often misinterpreted as causality. A study found that as more firefighters were called to a blaze, the greater the damage to the property. This led the city’s mayor to impose a hiring freeze and reduce the firefighting budget, thinking that more firefighters were somehow causing the damage.

In truth, the opposite was true. The larger the fire, the more firefighters were required to fight it, and the more damage the fire would naturally cause. The correlation between the number of firefighters and the amount of damage resulted from the fire’s size, not the firefighters’ actions. The more intense a fire, the greater the destruction and the more resources needed to extinguish it. The firefighters were not responsible for the destruction; they were responding to a crisis that was already far beyond their control. The mayor’s decision to cut resources based on this false causality could have had detrimental consequences, weakening the city’s ability to respond effectively to future emergencies. This situation underscores how easily a simple correlation can lead to flawed policies.

Employee Motivation and Corporate Profits: A Tangled Web

In business, it’s often claimed that motivated employees lead to higher corporate profits. This assumption is common in management literature and corporate training, but it rests on shaky ground. While it may sound intuitive that motivated workers will drive greater success for a company, the reality might be far more complex. Motivation in employees is often a reflection of the broader health of the company rather than the cause of that success.

Motivated employees may be a natural byproduct of a thriving, profitable company. When employees see that the company is doing well, they are likely to feel more secure, valued, and inspired. This environment fosters motivation. However, to claim that motivation directly causes profitability ignores the possibility that the company’s success is what fuels employee engagement in the first place. The increased motivation may simply be a reaction to a growing business and positive company performance.

Moreover, when analyzing the relationship between corporate boards and profitability, there’s another example of false causality at play. Some studies suggest that having more women on a board of directors leads to greater company profitability. While this correlation might be appealing to those advocating for gender diversity, the causality is far more nuanced. In many cases, highly successful companies, with their strong financial performance and positive reputations, may be more likely to recruit women to their boards. The presence of women does not necessarily create the profit but is instead a reflection of a company that is already successful and looking to expand diversity. This is another instance where correlation does not imply causality, and simplifying complex relationships leads to incomplete conclusions.

The Myth of Alan Greenspan’s Genius

Alan Greenspan’s tenure as Chairman of the Federal Reserve was often seen as synonymous with economic prosperity in the U.S. during the 1990s. His speeches, filled with intricate and cryptic language, made him a revered figure, and many believed his monetary policies were directly responsible for the country’s economic success. However, with the passage of time and a deeper understanding of global economic forces, it’s become clear that Greenspan’s role was much less decisive than once thought.

The real driver of the economic boom during his time in office was the symbiotic relationship between the U.S. and China. During this period, China emerged as a major low-cost producer, flooding the global market with inexpensive goods. Additionally, China became one of the largest buyers of U.S. debt, creating a flow of capital that helped fuel the U.S. economy. Greenspan’s policies were not the primary cause of the prosperity; they were simply aligned with broader global trends, particularly the integration of China into the world economy.

Greenspan’s reputation as an economic genius was built on the mistaken belief that his actions were the key to the nation’s success. In reality, his policies were largely a reaction to global economic shifts. The correlation between his leadership and the economic success of the time does not imply causality. Instead, it was the broader global economic environment—shaped largely by China’s rise—that was the true engine of growth. This example underscores how false causality can elevate individuals to mythic status based on coincidental timing.

Hospital Stays and Patient Health: A Misleading Association

A widely circulated belief in healthcare circles is that long hospital stays are detrimental to patients’ health. Health insurers, seeking to minimize hospitalization costs, have championed this view, suggesting that patients should be discharged as quickly as possible to improve their overall well-being. However, this logic oversimplifies the situation and ignores the deeper context behind long hospital stays.

In reality, patients requiring longer stays in the hospital often deal with more complex and serious medical conditions. Their extended stays are a reflection of the severity of their illnesses, not a sign that hospitals are inherently harmful. Shorter stays may benefit less serious cases, but extended care is necessary for proper treatment and recovery for those with more critical health issues. The correlation between long hospital stays and worse health outcomes does not imply that longer stays are the cause of poor health. Instead, the severity of the condition is the underlying factor, with prolonged stays being an inevitable consequence of serious illness.

By mistaking correlation for causality, policymakers might make decisions that prioritize cost savings over patient care. Reducing hospital stays without considering the needs of patients could result in poorer health outcomes and undermine the effectiveness of healthcare systems. This example highlights the importance of considering the full context before drawing conclusions based on surface-level correlations.

Shampoo and Strong Hair: The Power of Branding

When advertising shampoo products, companies often claim that using their product will result in stronger, healthier hair. While there may be some truth to the effectiveness of certain ingredients in promoting hair health, the underlying assumption in these advertisements is that the shampoo itself is the direct cause of stronger hair. However, this overlooks a more plausible explanation: women with naturally strong or thick hair are more likely to choose shampoos that promise to enhance these qualities.

The marketing of “shampoo for thick hair” targets a specific consumer group—those who already have thick hair and are looking to maintain or enhance its strength. The shampoo itself does not create stronger hair; rather, it serves as a product that aligns with the needs of individuals who already possess healthy hair. The correlation between using a specific shampoo and having strong hair is an example of false causality. The real cause of strong hair is genetic and environmental factors, and the shampoo is simply a tool that complements these natural traits.

This example illustrates how branding and marketing can manipulate consumers into believing that a product is the cause of a result that is actually driven by other factors. By focusing on the correlation between shampoo and hair strength, advertisers can create the illusion of causality, even though shampoo is not the primary factor influencing hair health.

Books and Academic Success: A Misguided Link

A common study suggests that students who have more books in their homes tend to perform better academically. This finding has been widely used to promote the importance of reading and the value of owning books. While there is some merit to the idea that exposure to books can foster a love for learning, the correlation between having books at home and academic success is far more complex than it appears.

The truth is that the presence of books in the home often reflects the parent’s educational background. Educated parents are more likely to value education, create a supportive learning environment, and provide resources like books to their children. This parental involvement plays a much more significant role in a child’s academic performance than the mere presence of books on a shelf. The real cause of academic success is not the number of books in the home but the parents’ level of education and their investment in their child’s education.

Thus, the correlation between books in the home and academic achievement is an example of false causality. While books may play a supporting role in a child’s education, it is the environment created by educated parents that has a far greater influence on their academic outcomes. This example highlights the importance of looking beyond surface-level correlations and understanding the deeper factors at play.

Storks and Babies: A Classic Example of False Causality

One of the most absurd examples of false causality comes from the correlation between the number of storks and the birth rate in Germany. From 1965 to 1987, the number of stork pairs in the country declined in tandem with a drop in the birth rate. The lines appeared nearly identical when these two trends were plotted on a graph. This led to a humorous, yet entirely false, conclusion that storks were somehow responsible for delivering babies.

In reality, the decline in the stork population and the birth rate was simply a coincidence. The correlation between these two factors was purely coincidental, with no causal link between the two. The decline in the stork population was due to factors like urbanization and changes in agriculture. At the same time, the decrease in birth rates reflected broader social changes, such as shifting family structures and cultural trends. This example is a humorous reminder of how easily seemingly identical trends can mislead us without understanding the underlying factors.

The Takeaway: Correlation is Not Causality

The above examples demonstrate how false causality can mislead us into incorrect conclusions. Whether it’s misinterpreting the relationship between firefighters and fire damage or believing that storks deliver babies, we often assume that correlation equals causality. It’s crucial to recognize that just because two things occur together does not necessarily mean one is causing the other. In many cases, deeper factors are at play that we may not immediately recognize. By examining relationships more critically and understanding the broader context, we can avoid falling into the trap of false causality and make more informed decisions.

Conclusion

The allure of causality often entices us to draw connections where none truly exist or attribute causes and effects incorrectly. By recognizing the prevalence of false causality, we can approach claims and correlations with skepticism, analyzing them critically and avoiding fallacious conclusions. Understanding the complexity of cause and effect enables us to navigate a world that is more nuanced and unpredictable than it might initially seem.

This article is part of The Art of Thinking Clearly Series based on Rolf Dobelli’s book.