Reasoning together or against each other? Learning outcomes of deliberative versus disputative argumentation.

Theoretical and empirical work suggests that deliberative argumentation-dialogue characterized by joint and issue-driven reasoning and critique-is more conducive to conceptual learning than disputative argumentation, which emphasizes interpersonal competition during disagreement.However, experimental evidence that isolates the effect of these differences in rhetorical style from other dialogue features remains limited.We report on two randomized controlled experiments that examined how deliberative versus disputative argumentation influences conceptual understanding of natural selection.In Study 1, undergraduate students (N 5 58) learned about natural selection and then engaged in chat-based argumentation with a disagreeing confederate on their solutions to transfer tasks.The confederate's verbal behavior was scripted to evoke critical discourse on the explanations, while controlling for content, length, arguments, and types of dialogue moves, but differing in rhetorical style (disputative/deliberative).In Study 2, a new sample (N 5 88) read either a deliberative or a disputative dialogue between two peers.Across both studies, deliberative argumentation resulted in greater conceptual understanding than disputative argumentation, after controlling for pretest differences.Moreover, rhetorical style affected participants' sociocognitive perceptions: Those exposed to deliberative argumentation rated their partner and the dialogue more positively and showed greater willingness to revise their initial explanations and collaborate again.Taken together, these findings provide robust experimental evidence that rhetorical style plays a pivotal role in argumentation for conceptual learning. Educational Impact and Implications StatementLearning through discussion with a peer who disagrees can support students' understanding of complex topics that are prone to misconceptions.This research shows that how discussion is framed by educators and handled by discussants matters.When discussions are framed as collaborative efforts to understand the topic-rather than as competitions to win an argument-students develop a deeper and more accurate understanding, as demonstrated here with natural selection.This effect was observed both when students actively participated in discussions and when they observed them.These findings suggest that fostering critical yet respectful engagement with different views, in both classrooms and online learning environments, may strengthen conceptual understanding and openness to revising one's views.