 Controversies about reductionism have been formative of scientific pluralism and served as a focal point for the articulation of general pluralist epistemological and metaphysical frameworks. The fading of reductionism as a general ideology in philosophy of science, however, has also shifted the attention of many pluralists away from intertheoretic reduction towards heterogenous relations between explanations, aims, models, practices, and institutions in scientific practice. In some cases, this shift towards “philosophy of science in practice” (Ankeny et al. 2011) has led to challenges not only of reductionism but also of antireductionism as a general account of the relations between scientific theories. Some pluralists therefore advocate for “metaphysical abstinence” (Ruphy 2005) in the sense that pluralists should make temporally qualified arguments in specific settings of scientific practice rather than formulating pluralism as a general account of the structure of science that is grounded in a general metaphysics of disunity.