The article raises the question of how a person argues for social change by compromise. The study is about the leading theorist of the reformist Swedish Social Democratic Party (SAP), Ernst Wigforss, and how he argues for a compromise in the relations between capital and labour. My hypothesis is that social change is argued as necessary, possible, and desirable. The guiding idea for the analysis is to use Quentin Skinner's understanding of political thought and its expression as a political manoeuvre bounded by a historically given context. However, the latter needs to be specified as an analytical concept, as well as audience and interest. Despite his efforts Wigforss failed to create an agreement about new relations between capital and labour. His problem situation and his efforts to work through the problem mirror a general political problem, the possibilities of reformism to convert the existing society on crucial issues. More specifically, however, in his effort to redefine what the interest of each party should be, Wigforss had to consider the character of the object of conflict he was addressing, as this determined what the interest of each party was, and the sort of compromise that might be reached.