Moral trade-offs reveal foundational representations that predict unique variance in political attitudes.

Moral Foundations Theory (MFT) explains variation in moral judgements on the basis of multiple innate, intuitive foundations and has been subject to criticism over recent years. Prior research has tended to rely on explicit self-report in the Moral Foundations Questionnaire (MFQ). In contrast, we seek to capture intuitive choices between foundations in a novel task - the Moral Foundations Conflict Task (MFCT). Across four studies, responses on this task reflect foundations measured by the MFQ (study 1), are not altered under cognitive load or reduced cognitive control (studies 2a and 2b); and explain unique variance in political orientation and related constructs (study 3). Furthermore, using responses and response times generated on the MFCT, we present a computationally explicit model of foundation-related intuitive judgements and show that these patterns are consistent with the theoretical claims of MFT. These findings show that the MFCT outperforms the MFQ and can contribute to the understanding of moral value conflicts, furthering debate on the nature of moral values.