Programming language research is becoming method conscious. Rigorous mathematical or empirical evaluation is often demanded, which is a good thing. However, I argue in this essay that concept analysis is a legitimate research approach in programming languages, with important limitations. It can be used to sharpen vague concepts, and to expose distinctions that have previously been overlooked, but it does not demonstrate the superiority of one language design over another. Arguments and counter-arguments are essential to successful concept analysis, and such thoughtful conversations should be published more.