Science deniers question scientific milestones and spread misinformation, contradicting decades of scientific endeavour. Advocates for science need effective rebuttal strategies and are concerned about backfire effects in public debates. We conducted six experiments to assess how to mitigate the influence of a denier on the audience. An internal meta-analysis across all the experiments revealed that not responding to science deniers has a negative effect on attitudes towards behaviours favoured by science (for example, vaccination) and intentions to perform these behaviours. Providing the facts about the topic or uncovering the rhetorical techniques typical for denialism had positive effects. We found no evidence that complex combinations of topic and technique rebuttals are more effective than single strategies, nor that rebutting science denialism in public discussions backfires, not even in vulnerable groups (for example, US conservatives). As science deniers use the same rhetoric across domains, uncovering their rhetorical techniques is an effective and economic addition to the advocates’ toolbox.
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The authors thank B. Wippert, T. Steinke, J. Gerlach and M. Schwarzer for their help collecting the data and developing the stimulus material and L. Korn for support visualizing Fig. 2 and Supplementary Fig. 2. The authors are also grateful for the valuable input from K. Habersaat. Parts of the study were funded by grants to C.B. from the German Federal Ministry for Education and Research (BMBF) via the interdisciplinary and trans-sectoral consortium InfectControl2020 to the University of Erfurt (no. 03ZZ0819A) and the German Research Foundation to C.B. (no. BE3970/11-1). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. No other funding bodies were involved.
The authors declare no competing interests.
Peer review information: Primary Handling Editor: Aisha Bradshaw.
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Nature Reviews Microbiology (2019)