Don’t think it’s a good idea! Four building sites of the ‘ideas school’

Ideational explanations of policy change are popular in the fields of political economy, comparative politics and policy analysis. And yet, to make the case for ideational explanations, we must make further progress on the nature of ideas, where they come from, what they consist of, and how they change over time. We highlight four critical building sites concerning the definitional aspects of ideational explanations, micro-foundations, mechanisms and the difference between ideational and cognitive analysis. We make recommendations on how to carry out work in the building sites and describe the range of suggestions and ways forward found in the articles of this Symposium. We also suggest cross-fertilising political science with the findings of neighbouring disciplines that have developed empirically robust models of ideation and cognition.