Assessing the Robustness of the Relationship between Tolerance and Intelligence

Abstract

Introduction: Individual differences in intelligence have been repeatedly found to be positively related to tolerance towards, and support for, the rights of groups different from one’s own. These findings hold true even when considering groups individuals dislike. This relationship has been explained in terms of both direct effects – whereby more intelligent people form more cognitive and less visceral opinions about other groups – and indirect ones, where the relationship represents the effects of phenomena like education or urban living, that have also been argued to give rise to higher intelligence and greater tolerance for others. Methods: To assess the robustness of this association to a plethora of common alternative explanations, we conducted a Specification Curve Analysis with the data from the U.S.-based General Social Survey (Nspecification max >15000). This method fits all possible configurations of a model that are possible with a set of variables, making it uniquely well-suited for robustness testing. Results: We found that the relationship was almost wholly robust to many alternative explanations, and in those cases where the relationship became null, it was likely the result of small sample sizes for a given specification. Conclusion: Intelligence and tolerance are strongly and consistently related.