Overview

This handbook addresses a specific problem at the heart of climate communication: conspiracy theories are not simply wrong beliefs that can be corrected with better information — they operate according to a distinct cognitive logic that makes them self-sealing, socially contagious, and resistant to standard debunking.

The handbook first explains why conspiracy theories are psychologically appealing, and why social media dramatically amplifies their spread. Second, it provides a taxonomy of conspiratorial thinking, summarised in the acronym CONSPIR (Contradictory, Overriding suspicion, Nefarious intent, Something must be wrong, Persecuted victim, Immune to evidence, Re-interpreting randomness). Third, it offers communication strategies for the general public and committed conspiracy theorists

Key Findings

• Exposure to conspiracy theories causes harm even among non-believers. Mere exposure to a conspiracy theory, without endorsing it, decreases people's intentions to engage in politics and to reduce their carbon footprint.

• Climate denial is structurally conspiratorial. When climate deniers encounter information about climate change, their most common response is conspiratorial in nature. Climate denial is also cross-domain.

• Prebunking (inoculation) outperforms debunking for conspiracy theories. Preemptively warning people that they may be misled, and explaining the flawed reasoning behind conspiratorial thinking, confers resilience before exposure.

Stand out data points

• 64% of all comments in an analysis of over 2 million comments on the r/conspiracy subreddit came from just 5% of posters who exhibited conspiratorial thinking — with the single most active author producing 896,337 words (twice the length of The Lord of the Rings).

• In a Twitter analysis of Zika virus coverage, the number of propagators of conspiracy theories was more than double that of debunkers, quantifying the structural asymmetry that climate advocates operate in.

• Sharing of conspiratorial climate-denial posts on Facebook was reduced by asking users four questions before sharing (Do I recognise the news organisation? Does the information seem believable? Is it written professionally? Is it politically motivated?), demonstrating that low-cost critical thinking prompts can meaningfully slow misinformation spread.

Examples of how Understories uses this research

• Emotional resonance: The handbook shows that conspiracy theories fill psychological needs for control and certainty in the face of threat. Messages that amplify threat without restoring a sense of control or efficacy may inadvertently increase susceptibility to conspiratorial counter-messaging.

• Credibility: The CONSPIR framework gives Understories a diagnostic tool for assessing whether a message's own credibility claims inadvertently mirror conspiratorial patterns — e.g., framing industry or government as unambiguously nefarious without evidence. This risks alienating non-conspiratorial audiences and feeding conspiratorial ones.

• Beneficence: The handbook is explicitly oriented toward protecting the public from harmful disinformation and toward equipping communicators to do the same ethically — through prebunking, empowerment, and evidence-based response rather than manipulation or ridicule of ordinary audiences.

Key quote

"Conspiracy theories may be deployed as a rhetorical tool to escape inconvenient conclusions. The rhetoric of climate denial is filled with incoherence — but it does not follow that climate denial is irrational. On the contrary, denialist rhetoric is an effective political strategy to delay climate action by undermining people's perception of the strength of scientific evidence."

© The handbook is freely available for download from the Center for Climate Change Communication at George Mason University and hosted on the University of Bristol research portal. Cite as: Lewandowsky, S., & Cook, J. (2020). The Conspiracy Theory Handbook. George Mason University.

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