Although contemporary dialectical logic recognizes an important role for the opponent in argumentation, it remains loyal to the idea that arguments are supportive. In this paper, it is argued that because of this dialectical logic does not take seriously its own dialogical perspective. Without acknowledging a substantial role for rebutting factors in argumentation, the role of the opponent remains secondary. Toulmin’s understanding of the rebuttal suggests a way to incorporate such a substantial role of the opponent.