Two-Dimensional Machiavellianism: Shortening the Scale and Expanding the Nomological Network to Political Psychology

For more than half a millennium, Niccolò Machiavelli's ideology has substantially influenced political thought. This research builds on the recent advancements in assessing Machiavellianism as a personality trait, aiming to recontextualize its relevance by investigating its association with key political attitudes. Initially, we created a six-item Two-Dimensional Machiavellianism Scale - Short Form (TDMS-SF) through item response theory and confirmatory factor analysis, utilizing a substantial international sample (n = 4769). Subsequently, we verified the scale's psychometric consistency and parameter stability within two distinct nationally representative samples from the U.K. (n = 819) and the U.S. (n = 810). We then investigated the nuanced interplay between Machiavellianism and three fundamental political attitudes in these two samples - ethnocentrism, nationalism, and authoritarianism. Specifically, structural equation modeling demonstrated consistent associations between Machiavellianism's two facets, view and tactics, and ethnocentrism (intergroup and intragroup), nationalism, and authoritarianism. Authoritarianism related positively to views, but negatively to tactics. This study not only refines the measurement of Machiavellian traits but also refines their complex interrelations with pivotal political attitudes, demonstrating the strength of the two-dimensional model.