Barnum Effect

What is the Barnum Effect?

The Barnum effect, also commonly referred to as the Forer Effect, describes when individuals believe that generic information, which could apply to anyone, applies specifically to themselves.

Where this bias occurs

Similarly, professions such as tarot card readers, magicians, and psychics are known for using the Barnum effect within their practices. This effect is also present in less obvious careers and industries, with digital companies such as Netflix, Spotify, and Facebook using the cognitive effect to better their products and make them more personalized. Personalized features within the digital products, like personally curated movie lists and specialized music playlists for each user, gives the illusion of a customized product to customers using Netflix and Spotify. In reality, these technology companies effectively use the Barnum effect to provide software users with the illusion of a personalized product.

Individual effects

Our inability to distinguish between general and personalized feedback, products, or content can lead to poor decision-making if we are left unaware of the Barnum effect. This bias takes advantage of our gullibility and well-meaning nature, which can be impactful if it involves making real-life choices that could profoundly affect our future. Individuals who make decisions influenced by this effect are unable to logically analyze their decisions and their possible outcomes, in order to make appropriate choices.

Systemic effects

The Barnum effect can systematically impact how larger companies engage and interact with their customers and create customer relationships. Commonly seen in marketing and engagement campaigns, elements of the Barnum effect provide customers with the impression of product customization. When executed correctly, the Barnum effect can strengthen customer buy-in and improve customer loyalty. Companies make customers feel as though they are personally interacting with the brand. As companies develop more sophisticated tactics to target their customers, we can expect more examples of the Barnum effect integrated into our goods and services.

Why it happens

The Barnum effect is a common cognitive bias, which results from our natural tendency to attach personal meaning to general statements. The Barnum effect is related to the cognitive bias known as subjective validation, also referred to as the validation effect. Subjective validation occurs when an individual considers information correct if it has personal significance, which we subconsciously do by identifying a relationship between two unrelated events. Like subjective validation, the Barnum effect results when individuals take a vague statement and find meaning specific to themselves by connecting the two separate entities.

Additionally, the Barnum effect seems to work exceptionally well regarding positive statements, inversely meaning that more critical remarks typically receive more skepticism from individuals.

Individuals like to be complimented, and will more likely accept positive comments about themselves and believe them to be accurate, even if they are general and vague. The Pollyanna Principle details this phenomenon, which is also commonly referred to as the positivity bias. The Pollyanna Principle occurs when an individual assumes better accuracy of descriptive statements when they are positive.5 Subconsciously, individuals are biased to accept praise and reject criticism easily.

Why it is important

In being aware of this effect, the everyday person can be attentive of scenarios where one can be easily influenced. Those who are skeptical of general horoscopes and wary of psychic advice tend to not let their own life be influenced by it.

How to avoid it

As in many situations, awareness and skepticism are crucial to avoiding certain cognitive tricks. Though an individual may enjoy checking their horoscope, knowledge of the Barnum effect can prevent one from being gullible and aid one in making informed decisions on it moving forward.

Though merely being aware of cognitive effects such as the Barnum effect does not ensure that one will not fall privy to its illusion, awareness does provide a starting point to ensure that both individuals and organizations avoid using the Barnum statements malicious, or are affected by the bias subconsciously.

How it all started

The Barnum effect coined its name after the famous 19th-century entertainer P.T. Barnum, whose life story inspired the film The Greatest Showman, and who famously said that

“A sucker is born every minute.” The statement refers to people’s gullible nature and their desire to believe what they are told about themselves, explicitly referring to the circus industry P.T. Barnum worked in.

The name “Barnum effect” was first in 1956 by American clinical psychologist Paul Meehl. The term was adopted after the psychologist expressed his frustration towards other psychologists, who were making general statements about their patients. Paul Meehl saw this as negligent, especially within his practice and towards their patients.

More officially, the Barnum effect was first investigated by Professor Bertram R. Forer, hence the interchangeable title for the bias, which is also commonly referred to as the Forer effect. Dr. Bertram R. Forer was an American psychologist, most famous for his work on the aptly titled Forer effect. He conducted what is known as the original bias’ experiment in 1948 on the cognitive effect. His experiment tested his students by providing his class individual personality surveys and generalized feedback. He informed his students that each personality survey would be first analyzed, and then given back with personal feedback on each student’s results. Instead, the professor gave the students the same general, unspecific feedback, regardless of their personality test results.

The feedback included general phrases such as “you have a great need for people to like and admire you,” or “you have a tendency to be critical of yourself.” After receiving the initial feedback, the students evaluated the feedback quality, giving it a score between five (incredibly accurate), to zero (not accurate at all). The experiment was a success, due to the average student rating having been a 4.26, giving the experiment an impressive accuracy rating, even though the feedback provided was general and the same for all students.

Example 1 – Horoscopes

One of the oldest and most common examples of the Barnum effect can date back nearly 2,000 years when horoscopes first originated and used for their predictive powers. Like magicians and palm readers, these professions have succeeded in convincing many people in their predictive ability.

Using the Barnum effect to describe general and common personality traits in ways that seem unique and special to a singular individual, horoscopes appeal to individuals globally and have garnered incredible popularity. Horoscopes provide readings and predictions for twelve different types of profiles described as sun-signs, split up into equal sectors of the sun’s path. The horoscope profiles are known globally and include Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, Pisces. Based on an individual’s time and location of birthday, everyone in the world can fall within one of these horoscopes. Horoscopes vary in content but typically provide general descriptions of a group’s personality traits while also providing future predictions on things regarding career, love life, family, and personal development.

Susan Miller, the famous astrologer and horoscope writer, generates lengthy monthly horoscopes for each horoscope type. Though historically, Susan Miller has wrongly predicted many famous world events, she is one of the world’s most renowned horoscope writers. Her sites are the most heavily trafficked horoscope website in the world. Her success is due to her ability to write lengthy, and generally uplifting vague passages for her readers. Using the Barnum effect, Susan gives readers a sense of connection to her texts; hundreds of thousands of people believe her predictions are relevant to themselves specifically.

Example 2 – The “For You” Page

Personalized digital products provide a modern-day example of ways the Barnum effect can engage customers and provide them with better product experiences. The Barnum effect can be present in the digital products we consume and use in our day-to-day lives. Users commonly favor digital providers such as Netflix and Spotify due to the personalized features the products have ready, such as recommended videos and customized music playlists, that curate content “just for us”.

Though the seemingly customized products give users a sense that the applications cater to each individual, in reality, the different digital companies offer vague personalized services to each of their clients. Yes, machine learning aids in developing these general recommendations, but this is also paired with the Barnum effect to deliver customized products successfully.

Technology is currently not yet able to give everyday users the amount of customizable content we assume we demand from our products. Hence, the Barnum effect provides a sense of personalization without full delivery on these technology companies. The perception that these services are customized, in turn, make a customer feel valued, and more willing to continue to use, and stream from these companies.


What it is

The Barnum effect is a cognitive bias that occurs when individuals believe that generic personality descriptions and statements apply to themselves. In reality, the description is general and vague enough to apply to almost everyone.

Why it happens

The Barnum effect occurs due to our brain’s natural tendency to attach personal meaning to general statements. Additionally, positive comments are more naturally accepted by the average person as relevant to themselves, as humans are less likely to believe general critical statements.

Example #1 – Horoscopes

Horoscopes serve as a classic example of the power of the Barnum effect. Horoscopes provide 12 different profiles based on one’s location and time of birth, categorizing their personality traits and providing future descriptions of things regarding career, love life, family, and personal development. The Barnum effect helps readers make connections between vague texts and their own lives.

Example #2 – How Netflix and Spotify pretend to know us

Personalized digital products provide a modern-day example of ways the Barnum effect is used to engage stakeholders and create better products and services for customers. Netflix’s “Just for You” movie lists, and Spotify’s weekly personalized music playlists, give software users a sense of customization and personalization.

How to avoid it

Awareness and skepticism are vital in recognizing the Barnum effect in your everyday life. Though merely being aware of cognitive effects such as the Barnum effect does not ensure that one will not fall privy to its illusion, awareness does provide a starting point to ensure that both individuals and organizations avoid using the Barnum statements maliciously or are affected by the bias subconsciously.

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