This paper presents some proposals for social science advanced by Otto Neurath, focusing on scientific utopianism. Neurath suggests that social scientists should formulate ideals of social arrangements in utopian style, aiming at discussing scientific proposals with a community. Utopias are deemed as models of social science, in the sense proposed by Nancy Cartwright. This view is contrasted with the claim that scientism might lead to dystopian consequences in social planning, drawn from Aldous Huxley’s fiction and from Paul Feyerabend’s philosophy of (...) science. Thus, social science displays a unusual feature: sometimes a model has to be called off, in spite of its perfect functioning, because it brings about unwanted consequences. In the planning of a free democratic society, this ambiguity of utopia and dystopia is highly desirable, for it stimulates essential debates. Social science, therefore, is to be regarded from a plural and fallibilist standpoint. (shrink)