Persuasive Web Design, Part 19: The Barnum Effect

P.T. Barnum (of circus fame) was a man of many talents. For example, he could take one look at a man, then wow him with a “remarkably accurate” description of his personality.

Barnum would say things like, “Sometimes you’re shy, but you can also be a real stage ham.” And his subject would say, “Yes, that’s so true!”

But Barnum was no Sherlock Holmes (or even Dr House). He had little knowledge of science, no special gift for deductive reasoning. Rather, Barnum’s genius was his realization that most people share the same strengths and weaknesses.

In reality, Barnum gave pretty much the same appraisal to everyone. His trick was to sound highly specific, while in fact remaining vague enough that his observations would apply almost universally.

The Barnum Effect is what keeps psychics, fortune tellers and astrologers in business. Think your horoscope was remarkably accurate today? Read that of another sign and be honest: is it not equally accurate?

Putting Barnum to the Test

In 1948, psychologist Bertram R Forer demonstrated the power of The Barnum Effect.

First, he gave his students “personality tests”. Then, he gave each of them a “personality analysis”.

Forer told his students that each analysis was unique, based on their responses to the test. And he asked them to rate the accuracy of their analysis, on a scale of 0 to 5.

On average, students rated the accuracy at 4.26 (very good to excellent). Yet in reality, all students got the same analysis. It included assessments like:

• You have a great need to be liked and admired.
• You tend to be overly critical of yourself.
• You have a great deal of unused capacity which you haven’t turned to your advantage.
• While you have some personality weaknesses, you are generally able to compensate for them.
• Disciplined and self-controlled outside, you are sometimes worrisome and insecure inside.
• At times, you have serious doubts as to whether you have made the right decision.
• You prefer a certain amount of variety; you become dissatisfied when hemmed in by restrictions and limitations.
• You are an independent thinker and do not accept others’ statements without satisfactory proof.
• You find it unwise to be too frank in revealing yourself to others.
• Some of your aspirations tend to be pretty unrealistic.
• Security is one of your priorities in life.

Note that these statements sound quite specific… but could actually apply to just about anyone. (Forer had simply pulled them from Horoscopes.)

Follow-up studies showed that The Barnum Effect is strongest where:

• Subjects believe the analysis is customized for them
• Subjects believe in the authority of the evaluator
• The analysis lists mainly positive traits (or clouds with silver linings)

The Barnum Effect and Persuasive Web Design

When developing your online communications, keep The Barnum Effect in mind. It’s often helpful in developing copy that resonates with customers. And when your copy “rings true”, customers will tend to trust you more and be more willing to engage.

“But my site is B2B!” you say? I’d argue that The Barnum Effect applies equally well to business owners as it does to consumers.

Many business owners share the same concerns and challenges, even if they think their problem is unusual. So find out what these shared problems and concerns are, and address them in your online communications

To your visitors, your messaging will appear tailor-made for them. Making your website much more persuasive.