First lines of the introduction: This chapter reflects on the diversity of approaches in political science and its associated challenges, comparing them with the risks of conforming to a single doxa and praxis. Alongside the fashionable and ubiquitous term “diversity,” I will use the concept of “pluralism.” It refers to the desirability of multiple opinions, even if they are not equally valued. John Stuart Mill powerfully argued that science would be “dead dogma” if it dismissed eccentrics and defenders of unpopular minority opinions (Lloyd, 1997). He insisted on the importance of pluralism and the pursuit of liberty, not just for political debate, but also for scientific progress. First, I will establish whether there is a dominant paradigm, as defined by Thomas Kuhn, with an aligned ontology and methodology (Hall, 2003), or parallel “research programmes,” a term coined by Imre Lakatos to designate concomitant scientific inquiries, based on each with a hard core of theoretical assumptions and auxiliary hypotheses. This implies distinguishing two levels of analysis: first, the existence of a consensus on the scientific method, the boundary work on what constitutes political science and what does not; second, the multiplicity of more specific theories that may be context-bound and fleeting in nature—what the “epistemological anarchist,” Paul Karl Feyerabend, referred to as scientific “fads” in Against Method (1975). There are plenty in political science: “the cultural turn,” the “neo-institutionalist” decade, the return of political psychology, and so forth.