The Half-Truth Effect and Its Implications for Sustainability

Misinformation on sustainability has become a widespread phenomenon in many different contexts. However, relatively little is known about several important determinants of belief in misinformation, and even less is known about how to debias that belief. The present research proposes and investigates a new effect, the half-truth effect, to explain how message structure can influence belief in misinformation. Two survey-based experiments were conducted to show that people exhibit greater belief in a false claim when it is preceded by a true claim, even if the two claims are logically unrelated. Conversely, when a false claim is presented before the true claim, it reduces the belief in the entire statement. Experiment 1 shows the basic half-truth effect. Experiment 2 investigates an individual difference, propensity to believe meaningless statements are profound, which impacts the half-truth effect. Both experiments also investigate debiasing of the false information. The results of the experiments were analyzed using analysis of variance and regression-based mediation analysis. Results show that belief in misinformation is dependent on message structure, and show that the order in which true and false elements are presented has a strong influence on belief in sustainability misinformation. Finally, we present a discussion of how policy makers can use these findings to identify those people who are most likely to be swayed by the misinformation, and then design responses to debias sustainability misinformation.