Go Green! Should Environmental Messages Be So Assertive?

Environmental communications often contain assertive commands (e.g., Greenpeace’s “Stop the Catastrophe”, Plant-For-The-Planet’s “Stop Talking and Start Planting” or Denver Water Campaign’s “Use only what you need”), even though research in consumer behavior, psycholinguistics, and communications, has repeatedly shown that gentler phrasing should be more effective when seeking consumer compliance. This paper shows that the persuasiveness of assertive language depends on the perceived importance of the issue at hand: recipients respond better to pushy requests in domains that they view as important, but they need more suggestive appeals when they lack initial conviction. We examine this effect in three laboratory studies and one field experiment using Google Adwords. Our findings refer to various environmental contexts (i.e., economizing water, recycling plastic containers, reducing air and sea pollution). The key implication of our findings is that issue importance needs to be carefully assessed (or affected) before the language of effective environmental campaigns can be selected.