Anecdotal Reasoning Fundamentals: Your Evidence Is Dumb

Anecdotal reasoning is using insight to back your claims. In other words, it’s arguing from the point of personal experiences or observations, not with science. “Anecdotal” in this sense means personal experience, self-reported claims, or eyewitness accounts of others. What is anecdotal in nature can be true or false, it just has not been proven by any scientific or legal rigor. So there is no safeguard against fabrication or inaccuracy. Think: testimonials advertised by a company for their product or service.

In the simplest terms, anecdotal reasoning is relying on non-scientific evidence to prove a point. An anecdote does not have any reliable proof to back it. It’s attractive and easy to think this way because it doesn’t require you to take time filtering rigorous arguments and scientific evidence. Most of us are too lazy, and would rather the quick conclusion. After all, if your friend’s grandpa smoked 40 cigarettes per day and lived to be 97, smoking isn’t so bad, right?

Anecdotal reasoning is sometimes also referred to as the Volvo fallacy. The origins come from a story about a man who needed a new car. He carefully read all kinds of studies and came to the conclusion that the Volvo was the best. The man was decided. Until, at a party, he spoke to a friend of his. This friend’s brother once had a Volvo. The Volvo sucked: it had all sorts of problems and always caused him trouble, enough for him to have eventually sold the car. What happens next? You guessed it, the man decides not to buy a Volvo after all.

Marketers love anecdotal reasoning. It’s easy to understand and a powerful way to persuade potential customers. With things that are mostly subjective — hotels, restaurants, art galleries, coaching services — testimonials are used to influence how the service is viewed. Well-known and highly-regarded people are paid to speak about the product or service in a positive light. Emotional personal stories are told to capitalize on customer concerns. The idea of such anecdotes is that they appear “clearly correct” while, in reality, being based on no evidence whatsoever.

Real-world instances of anecdotal reasoning:

• Healthcare: a patient hears a story about someone who experienced severe side effects from a particular medication. The result? The patient decides against taking the prescription, even if large-scale studies show that side effects are rare. Lesson: while individual experiences matter, they should be weighed against robust bodies of data.

• Consumerism: a friend recounts a negative experience with a particular smartphone brand. The result? You don’t buy that brand based solely on that story, without researching other reviews or product tests. Lesson: a single story never reflects the overall quality of the product, so it’s important to consider more evidence and perspectives.

• Finance: an investor hears about a startup that became wildly successful from a charismatic founder. The result? The investor becomes overly optimistic about similar ventures, and ignores the statistical evidence that most startups fail — 90 percent, sadly. Lesson: personal success stories can inspire, but they shouldn’t result in you taking riskier investments without objective data.

• Social Opinion: a political commentator might share a personal story of how a particular legislation ruined their life. The result? The narrative invades public opinion more than real data about the policy and skews their votes thereafter. Lesson: individual stories highlight important issues, but they need to be contextualized within larger trends to form any substantial opinion.

How you might use anecdotal reasoning as a mental model: (1) give it some backup — use anecdotes to illustrate issues, but complement them with statistical or empirical evidence later; (2) stay aware of the limits — be cautious of personal stories since they are subject to biases and rarely capture the full complexity of an issue; (3) balance logos and pathos — while anecdotes are emotionally compelling, balance them out with logical analyses and broader data points to see how common the experience is; (4) get them on the same page — anecdotes are an awesome communication tool to make data more relatable and a message more resonant, though you need to provide broader evidence for nuance afterward to make your claims substantial; (5) wear all the lenses — gather a variety of personal experiences instead of relying on just one narrative, be it your own or somebody else’s.