Forthcoming in Inquiry: An Interdisciplinary Journal of Philosophy 1 Ideology and Normativity: Constraints on Conceptual Engineering Paul-Mikhail Catapang Podosky UNIVERSITY OF MELBOURNE Where do the boundaries of the ‘should’ in conceptual engineering lie? Mona Simion (2017) suggests that the right kind of reason for an ameliorative project is epistemic: revising a concept should not come at the cost of epistemic loss. In this paper I argue that Simion’s epistemic constraint on conceptual engineering fails to make sense of important ameliorative projects. In virtue of the interdependence of thought and reality, sometimes conceptual engineering aims at epistemic loss. Given this, I offer an amendment of Simion’s epistemic constraint: epistemic loss is permissible in cases where the ameliorated concept has the capacity to causally influence the world, and can therefore make itself representationally accurate. I call this the Epistemic Limiting Procedure+ (ELP+). At the end of the paper, I suggest that we should examine a further question about the normative boundaries of ameliorative projects: What are the feasibility constraints on conceptual engineering?