On a slippery slope to intolerance: Individual difference in slippery slope beliefs predict outgroup negativity

Slippery slope beliefs capture the idea that a non-problematic action will lead to unpreventable and harmful outcomes. While this idea has been examined in legal and philosophical literatures, there has been no psychological research into the individual propensity to hold slippery slope beliefs. Across five studies and six samples (combined N = 5,974), we developed and tested an individual difference measure of slippery slope beliefs, finding that it predicted intolerance of outgroup freedoms above and beyond key demographic and psychological predictors (Studies 1–2 and 5). We also found that slippery slope beliefs predict intolerance of debated behaviors in two countries (Study 3), and that it predicted agreement with real-world slippery slope examples across the political spectrum (Studies 4–5).