When persuading a group, watch out for the charm of consensus

If you’re like most people, you probably instinctively prefer the first strategy, which emphasizes consensus, over the second, which relies on extremes. In fact, a new research led by Derek Ruckerprofessor of marketing at the Kellogg School, finds that people have a remarkably strong preference for consensus-based persuasive strategies.

“At times, people tend to gravitate toward having more people on their side at the expense of having people who are true supporters,” says Rucker. In fact, according to research, people will choose consensus-based strategies even in situations that are objectively inferior to edge-based strategies.

Consensus seeking, Rucker adds, can be an “effective strategy and even an objectively correct strategy in some cases, but the point is that we can get so attached to it that we misapply it.”

Consensus vs. Extremes

While much psychological research has looked at how people approach the task of persuading individuals—so much so that Rucker calls it “a staple of persuasion research”—little research has focused on efforts to influence multiple people at once. This is a surprising omission, given how many important decisions are made in group contexts. “It’s a situation we’re really in a lot where you’re surrounded by six people at the table who may or may not agree with you,” Rucker says.

When the research team—consisting of Rucker, Kellogg doctoral students Jesse D’Agostino and Mark Dyer, and Zakary L. Tormala of Stanford University—started thinking about the different approaches people might take, consensus and extremes seemed like two equally attractive paths. However, even among them, the researchers weren’t sure which would resonate more. After all, both are reasonable approaches. With an edge strategy, you have the advantage of ardent supporters. with a consensus strategy, you have the comfort of numbers.

Unsure of what would happen, the research team began with a simple experiment or “persuasion game” that allowed them to pit these two tactics against each other.

Participants in the study said they were giving a speech in hopes of convincing a group of ten people to support an idea. Their goal, the researchers explained, was to convince a simple majority of the group. Support can range from maximally positive to somewhat positive. Similarly, disagreement can range from maximally negative to somewhat negative.

Participants were then presented with diagrams depicting two different approaches to gaining group support and asked to choose between them. According to Strategy A – a consensus strategy – everyone in the group would support the idea, with eight people feeling somewhat positive and two feeling very positive. With Strategy B – an edge strategy – only six out of ten team members would support the idea, but five of them would feel very positive.

Importantly, both strategies achieved their stated goal of persuading the majority, just in different ways. Therefore, participants could not make a wrong choice when it came to winning this game. Although the choice was seemingly irrelevant, the consensus strategy was the most popular by a wide margin—of the 102 participants in the experiment, 88 (or 86 percent) chose Strategy A.

“We learned that people showed an overwhelming preference for consent,” says Rucker.

Testing the preference for consent

But how far does this preference for consent extend? Would people still choose a consensus-based strategy—even when it produced an outcome where people might lose in a battle of persuasion?

To find out, the researchers recruited 198 young participants. As in the previous experiment, these participants were told that they would give a speech with the goal of persuading the majority of their audience of ten to support their idea. This time, however, support was expressed numerically, with +5 indicating the strongest support and -5 indicating the strongest opposition.

Participants were then presented with four strategies from which to choose.

• In Strategy 1, all ten audience members were supportive (100 percent), with an average extreme of 1.40.
• In Strategy 2, eight members of the public expressed their support, one was neutral and one was in opposition. Compared to Strategy 1, this strategy had fewer people in support (80 percent) but a larger mean edge among supporters (2.60).
• In Strategy 3, four audience members expressed strong support, two were neutral, and four were opposed. This strategy had the largest mean edge among supporters (5.0) but the least number of people who supported (40 percent).
• Finally, on Strategy 4, six audience members were in favor and four were opposed. This strategy had less support than Strategy 1 (60 percent), but a larger mean edge among supporters (2.83).

It is worth noting that the researchers designed the paradigm so that all strategies except Strategy 3 achieved the participants’ goal of gaining majority support.

But the researchers introduced a new wrinkle. Half of the participants were told that a contestant would also give a speech and could, if successful, reduce each audience member’s support by a point or two. Under this condition, only Strategy 4—which emphasizes extremity more than consensus—would be guaranteed to counter the competitor’s attack and allow participants to guarantee success.

Finally, the researchers instructed both groups of participants—those who had learned about the competitor and those who had not—to choose their preferred strategy.

According to the results of the first experiment, the majority of participants in the no-competition group (57.8 percent) chose Strategy 1, and another 29.4 percent chose Strategy 2. In other words, 87.2 percent of participants chose a consensus-based strategy—another sign of the overwhelming preference for consensus.

In the competition group, 24.7 percent of participants understood that Strategy 4 was the only noncompetitive option. However, 37.6 and 29 percent still chose Strategies 1 and 2, respectively — that is, 66.6 percent chose a consensus-based strategy that put them at risk of losing.

“Some people get it,” D’Agostino explains. Essentially, these participants argue that a consensus-based strategy will not serve their interests in this scenario. “But the majority still follows consensus, even though it will make them more prone to defeat.”

Disruption of the consensus heuristic

For Rucker and his colleagues, the second study suggested that the preference for consensus may be a heuristic, a mental shortcut we use to make decisions, rather than a thought decision.

If consensus actually functioned more as a heuristic rather than a deliberate decision, the researchers reasoned, then it might be possible to undermine the shortcut by forcing participants to think about their decisions more carefully. So, for their latest experiment, they put the matter to the test.

The setup was similar to the previous experiment. Participants were divided into three groups—a competition group, a competition group in which participants were encouraged to think about their choice, and a no-competition group—and presented with two strategies. Strategy 1 had 70 percent support and an average edge of 3.0, while Strategy 2 had 90 percent support but an average edge of just 1.89. Against the competition, only Strategy 1 was unbeatable.

Participants in the competition group who were encouraged to think about their choice were then prompted to consider how a competitor’s actions could change the outcome in both strategies. The researchers also offered a small bonus for choosing a winning strategy. Together, these two procedural changes were intended to make this subgroup of participants pay more attention before making their choice.

In the absence of competition, participants once again aligned heavily with Strategy 2, which emphasized consensus over extremism.

In the competition group, as in the previous experiment, the preference for consensus decreased somewhat, but the majority of participants (62.6 percent) still chose Strategy 2, even though it was at risk of failure.

However, among participants in competition groups who were prompted to think about their choice more carefully, 73 percent chose the uncompetitive edge strategy.

Forcing people to think “turns the tide,” Dyer explains, because “the majority begins to realize that the competitor will win if they follow their instinct toward consensus.”

More to explore

Why is this happening; Rucker and team explored a few ideas. As social creatures, we tend to enjoy group harmony. the consensus appeal seems to arise, in part, because it feels more comfortable when a group is in general (if tepid) agreement than when there are strong voices on both sides of an issue. In addition, people also seem to believe that there is “safety in numbers” so that they cannot lose when they have more people on their side. Of course, as experiments show, this is not inherently true.

However, the research offers much more to explore. Rucker and his colleagues want to know if there are situations that might cause a strong preference for the ends. And they hope to adapt their “persuasion games” to mimic more complex real-world situations. For example, how might group persuasion tactics play out when two opposing perspectives are presented in succession, with opportunities for debate and rebuttal?

“Our work ultimately raises many more questions than it solves, which is what we want to do as academics,” says Rucker. “This is an aspect of the research that is both illuminating and fascinating.”