Proceedings of the Annual Meeting of the Cognitive Science Society

Framing issues as matters of non-negotiable values can increase the perceived intractability of debates. Focusing on theconcrete consequences of policies instead can facilitate conflict resolution. Using a topic model of Reddit commentsfrom January 2006 to September 2017, we show that the contribution of certain topics concerned with protected val-ues to the debate increased prior to the emergence of a public consensus in support of same-sex marriage and declinedafterwards. These topics related to religious arguments and freedom of opinion. In contrast, discussion of certain con-crete consequences (the impact of politicians stances and policy implications) showed the opposite pattern, their increasedprominence coinciding with improved public support for same-sex marriage after 2012. Our results reinforce the mean-ingfulness of protected values and consequentialism as relevant dimensions for describing public discourse and highlightthe usefulness of unsupervised machine learning methods in tackling questions about social attitude change.