Liking Technique #1: Similarity

Episode #3 of the course Persuasion science masterclass: Part II by Andy Luttrell

The first liking technique that we’ll consider is the “Similarity-Liking Technique” because in general, what research has shown again and again is that the more similar you are to someone, the more you like each other across a whole bunch of types of similarity. This is maybe one of the most common findings in social psychology: that similarity breeds attraction.

To be clear, this can be used as a technique by highlighting one’s similarity to the other person. If you know in advance that there’s some connection between you and the person you’re asking a favor of, you could be sure that the other person is aware that you share some kind of connection. We’ll look at two kinds of similarity today.

The first is “incidental similarity.” These are the kinds of things that you might not think on the surface are even meaningful, but simple similarities between you and another person create greater connection between you and a greater sense of liking for the other person. One intriguing case of incidental similarity is “name similarity.” There was a neat study in which researchers mailed surveys to people, asking them to complete them and return them by mail (Garner, 2005). Sometimes, though, the person sending the survey had a name that looked very similar to the recipient’s. For example, if your name was “Robert Greer,” you might get a letter from “Bob Gregar.” Other times, the name wasn’t specifically matched. Under ordinary conditions, 20% of people filled out and returned the survey. But when the person’s name in the letter was kind of similar to the person’s own name, nearly 40% of people filled out and returned the survey.

As another fun example of incidental similarity, consider a study on the “Shared Birthday Effect” (Finch & Cialdini, 1989). This study put participants into pairs, and each person learned the birthday of the other person. They found that for people with different birthdays, 34% agreed to do a favor for their partner. This compliance rate doubles, however, when the partners learned that they had the same birthday.

Beyond “incidental similarity,” there’s also power in shared likes and dislikes. One of the most powerful findings in the psychology of attraction is that we like people more when we know that they like what we like. Decades of research have shown this time and again, and it has a clear tie to persuasion.

As just one example, consider a study that tested what happens when people find out that someone else has the same opinions on a number of issues (Baron, 1971). When participants in the study learned that their partners held similar opinions, compared to cases when there was dissimilarity, they were more likely to comply with a request made by the partner—even if it was a large request. By highlighting similar opinions, you create a quick bond that results in greater influence.

Whether it’s an “incidental” similarity or one that’s more substantive, it’s clear that the likability that this similarity creates then translates into greater persuasion.

Tomorrow we’ll see another technique drawn from likability, which is that mere familiarity can make a big difference.

Recommended book

“Pre-Suasion: A Revolutionary Way to Influence and Persuade” by Robert Cialdini

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