Behavioral Contagion Could Spread the Benefits of a Carbon Tax


Robert H. Frank at the New York Times: “…Why, then, hasn’t the United States adopted a carbon tax? One hurdle is the fear that emissions would fall too slowly in response to a carbon tax, that more direct measures are needed. Another difficulty is that political leaders have reason to fear voter opposition to taxation of any kind. But there are persuasive rejoinders to both objections.

Regarding the first, critics are correct that a carbon tax alone won’t parry the climate threat. It is also true that as creatures of habit, humans tend to change their behavior only slowly, even in the face of significant financial incentives. But even small changes in behavior are greatly amplified by behavioral contagion — the social scientist’s term for how ideas and behaviors spread from person to person like infectious diseases. And if a carbon tax were to shift the behavior of some individuals now, those changes would quickly spread more widely.

Smoking rates, for example, changed little in the short run even as cigarette taxes rose sharply, but that wasn’t the end of the story. The most powerful predictor of whether someone will smoke is the percentage of her friends who smoke. Most smokers stick with their habit in the face of higher taxes, but a small minority quit, and still others refrain from starting.

Every peer group that includes those people thus contains a smaller proportion of smokers, which influences still others to quit or refrain, and so on. This contagion process explains why the percentage of American adults who smoke has fallen by two-thirds since the mid-1960s.

Behavioral contagion would similarly amplify the effects of a carbon tax. By making solar power cheaper in comparison with fossil fuels, for example, the tax would initially encourage a small number of families to install solar panels on their rooftops. But as with cigarette taxes, it’s the indirect effects that really matter….(More)”.