Joachim Andersen

Accelerated Learning

The Mere-Exposure Effect: Why We Like What We Know

A dark marble arcade at night with a long row of identical framed gold octagon prints along the wall under brass lamps, and one more identical print on a black velvet easel, beside glowing lanterns on a polished floor
The more often we see something, the more we tend to like it.


The Mere-Exposure Effect describes how we tend to like things more simply because we’ve seen or heard them before. A face, a song, a word or a brand doesn’t need to be explained, praised or rewarded to grow on us. Repeated, harmless encounters are often enough to make it feel safe, pleasant and right.

The essence of The Mere-Exposure Effect is to ask: “Do I actually prefer this, or is it just what I’m used to?”


Origin: The Student in the Black Bag

In February 1967, a news story told of a mysterious student at Oregon State University who came to class wrapped in a big black bag, with only his bare feet showing. None of the 20 students in the persuasion course taught by Charles Goetzinger knew who was inside, but over the weeks, their attitude toward the Black Bag changed from hostility to curiosity and finally to friendship.

The Polish-born American psychologist Robert Zajonc opened his 1968 monograph with this story. The idea that familiarity breeds liking went back at least to the German psychologist Gustav Fechner, who discussed it in his Vorschule der Aesthetik in 1876, but Zajonc was the first to test it systematically.

In one experiment, he showed 72 students twelve unfamiliar seven-letter words between 0 and 25 times each, and asked them to pronounce them. He then told them they were Turkish adjectives and asked them to guess whether each one meant something good or bad. The more often the students had seen a word, the more positive they guessed its meaning to be. He found the same pattern for Chinese-like characters and for faces from a university yearbook.


Key Concepts

  • No Awareness Needed
    In 1980, William Kunst-Wilson and Zajonc flashed irregular octagons five times each for just one thousandth of a second. Afterward, the students recognized the shapes they had seen at no better than chance, but still liked them better than new ones 60% of the time. We can come to like something without knowing we’ve ever seen it.

  • Strongest for the Unfamiliar
    In 1989, Robert Bornstein reviewed 208 experiments and found a reliable effect, strongest for brief exposures to things that were new to begin with. Something I already know well has less room to grow on me.

  • An Inverted U
    Liking usually rises over the first exposures and then levels off or declines. In 2017, Matthew Montoya and colleagues combined 268 such curves from 81 articles and found that, after a point, boredom takes over and more exposure can make us like something less.

  • Familiarity Feels Like Safety
    A likely explanation is that something we’ve met before without harm feels safe, and things we’ve seen before are easier to process, which we tend to mistake for liking. It also helps explain why liking is one of the principles of influence in What is the Psychology of Persuasion.


Some Examples

  • The Face in the Mirror
    In 1977, Theodore Mita, Marshall Dermer and Jeffrey Knight photographed women at the University of Wisconsin–Milwaukee and showed them a normal print and a mirrored print of their own face. 21 of 33 preferred the mirrored version, the one they see every morning, while most of their close friends preferred the true print, the face they see every day.

  • The Women in the Lecture Hall
    In 1992, Richard Moreland and Scott Beach had four similar-looking women attend a large college course 0, 5, 10 or 15 times, but never talk to anyone. At the end of the term, the students rated the women who had come more often as more attractive and more similar to themselves, even though the extra visits had made the women only slightly more familiar.

  • The Impressionist Canon
    In 2003, the psychologist James Cutting showed his Cornell students pairs of Impressionist paintings, where one painting in each pair is often reproduced in books and the other rarely. An earlier class had preferred the famous painting of each pair 57% of the time. Cutting then showed a new class the rare paintings four times and the famous ones once at the start of his lectures, for about two seconds each without comment. Weeks later, the new class preferred the famous painting only 48% of the time, suggesting that part of what makes a masterpiece is how often we’ve seen it.

  • Learning to Like Vegetables
    In 2003, Jane Wardle and colleagues asked parents of 2- to 6-year-olds to offer their child a small taste of a vegetable the child disliked every day for 14 days. The children who got the daily tastes came to like and eat more of the vegetable, while those in the two groups that didn’t get them (one that only got advice, and one that got nothing), did not change.


Applying The Mere-Exposure Effect

When I want to use this mental model, this is the simple process I follow:

  1. Question My Preferences
    When I feel drawn to a choice, I ask whether it’s better or just more familiar, whether it’s a product, a route to work, an investment or a way of doing things.

  2. Give New Things a Few Tries
    I try not to judge a new song, food, idea or person after a single encounter. Many things that feel strange at first grow on me once they become familiar.

  3. Show Up Regularly
    Being a familiar face makes people more comfortable with me, so I try to stay in touch, show up and be present, rather than only reaching out when I need something.

  4. Stay Consistent
    When I teach or present, I repeat my key message, and I keep names, colors and styles consistent, so that people get to know them over time.

  5. Separate Familiar from True
    When a claim feels obviously right, I ask whether it’s because I’ve seen the evidence or just because I’ve heard it many times before.

  6. Don’t Overdo It
    Because liking eventually wears off with too much exposure, I try to vary my message and leave some space, rather than repeating the same thing again and again.


Pitfalls and Limitations

  • Repetition can make lies feel true. In 1977, Lynn Hasher, David Goldstein and Thomas Toppino had students rate how true 60 plausible statements were, in three sessions two weeks apart. The statements that were repeated were rated as more likely to be true each time, whether they were true or false. This is known as the illusory truth effect.

  • Familiar isn’t better. Liking what I know can keep me stuck with old habits, products, people and ideas, and make me reject better options simply because they’re new.

  • Too much backfires. Because the effect follows an inverted U, overexposure can lead to boredom and irritation, and repeated contact with people or groups we already dislike can make us dislike them even more.

  • It can be exploited. Advertisers and propagandists repeat names and slogans because it works, so I try to notice when my sense of comfort with something was manufactured.


Related Mental Models

The Mere-Exposure Effect reminds me that much of what I like, trust and believe has been shaped by what I happen to have met most often. By noticing when familiarity is doing the choosing, I can give new things a fair chance, use repetition wisely and avoid mistaking the familiar for the true.



To learn more about mental models and philosophy,
check out: Wise: How to Attain a Deep Understanding of the World, History, Our Place in It, and How to Live Well



📚 Sources and References