I review and challenge the views on simplicity and its role in linguistics put forward by Ludlow (The philosophy of generative linguistics, 2011). In particular, I criticize the claim that simplicity—in the sense pertinent to science—is nothing more than ease of use or “user-friendliness”, motivated by economy of (cognitive) labor. I argue that Ludlow’s discussion fails to do justice to the diversity of factors that are relevant to simplicity considerations. This, in turn, leads to the neglect of crucial cases in which the rationale for simplification is unmistakably epistemic, as well as instances where simplicity is part of the content of substantive, empirical hypotheses. I illustrate these points with examples from the history of generative linguistics, such as: (a) the shaping influence exerted by simplicity, via its involvement in the notion of “linguistically significant generalization”, (b) its methodological and substantive contribution to the goal of explanatory adequacy, and (c) its central role in the Minimalist Program’s search “beyond explanatory adequacy”.