Beyond the Cultural Mediation Hypothesis: A reply to Dutton (2013)

• Predictions from the Cultural Mediation Hypothesis and an alternative are tested.
• Openness mediates the association between IQ and leftism.
• IQ measured at 11 years and older significantly predicts political orientation at 23.
• Support for both models is inconsistent.
• A novel model is proposed to account for the relationship between IQ and leftism.

The relationship between IQ and political orientation is an active and controversial area of research. In Dutton's 2013 criticism of one mechanism proposed to account for this relationship (the Cultural Mediation Hypothesis; CMH), it was argued that Openness to Experience and Agreeableness might better account for the positive association between political leftism and IQ than effortful control and cultural mediators. Various predictions derived from both Dutton's model and the CMH are here tested using the Block and Block dataset. Consistent with Dutton's predictions, Openness to Experience mostly mediates the relationship between IQ and leftism (measured using Block and Block's LIB/CON indicator), however problems with Openness to Experience substantially weaken the degree to which this supports his model. Support for the CMH is found in the form of significantly rising correlations between leftism measured in adulthood and IQ with increasing age, suggesting a role for childhood environment in shaping this association. Ultimately neither model is consistently supported by the data. It is suggested that personality and more broadly life history strategy may be an important determinant of whether a political orientation is extreme or moderately oriented. A modified CMH posits that the left/right axis may however be a largely cognitive dimension, with ideologies serving to signal intelligence and to encourage social and sexual selection, and with the basic elements of their content being largely bounded by prevailing cultural norms.