One of my favorite examples of the powerful urge to conform with the majority comes from an experiment he ran at Arizona’s Petrified Forest National Park. Conformity theory suggests the park service was sending exactly the wrong message when it posted signs saying:

Your heritage is being vandalized every day by theft losses of petrified wood of 14 tons a year, mostly a small piece at a time.

Here’s how his paper describes the experiment:

We gained permission from Petrified Forest National Park officials to place secretly marked pieces of petrified wood along visitor pathways.

Over five consecutive weekends, Cialdini and coauthors varied the signs seen at the entrance to each path. Some weekends, visitors saw a sign that, like the original park-service sign, emphasized the wrong norm:

Many past visitors have removed petrified wood from the park, changing the natural state of the Petrified Forest.

This wording was accompanied by pictures of three visitors taking wood.

Other weekends, visitors saw:

Please don’t remove the petrified wood from the park, in order to preserve the natural state of the Petrified Forest.

This wording was accompanied by a picture of a lone visitor stealing a piece of wood, with a red circle-and-bar symbol superimposed over his hand.

Sure enough the “many past visitors” framing lead to more than four times the amount of pilfering of petrified wood (7.92 percent vs. 1.67 percent). But what’s truly amazing is that putting up no sign at all did a better job than putting up a sign suggesting that “everybody does it”:

In a finding that should petrify the National Park’s management, compared with a no-sign control condition in which 2.92 percent of the pieces were stolen, the social-proof message resulted in more theft (7.92 percent). In essence, it almost tripled theft. Thus, theirs was not a crime prevention strategy; it was a crime promotion strategy. (Yes!, p. 22)

I’m not calling for the writers of Friday Night Lights to change the story arc. But Cialdini’s simple idea is that public service messages would do well to implicitly tell high-schoolers: “Be like most of your peers — don’t have sex while you’re in high school.”

Indeed, Cialdini has me thinking that all those “Above the Influence” commercials are seriously off base:

These commercials implicitly suggest that most of your peers are going to be using drugs and that you have to gird yourself to be above their influence. They are too close to the signs in the Petrified Forest. Instead of saying “Don’t do what most kids your age do,” they might say “Do what most kids your age do: just say no.”

We might want to start by finding out what high-schoolers think and correct misperceptions. These spots might be a lot more effective if they change their message to implicitly say: Most high-schoolers don’t use meth. Most high-schoolers don’t binge drink. In fact, most high-schoolers don’t use drugs at all.