 Discussions of downward causation are often connected to debates about whether biological systems exhibit emergent properties (cf., Alberghina &amp; Westerhoff 2005; Boogerd et al. 2005, 2007; Kolodkin et al. 2011). Emergence in the context of systems biology typically means that systems properties cannot be explained from the properties of parts. Discussions can center on epistemic questions about whether systems properties can be predicted from analyses of lower-level constituents (epistemological emergence) to debates on whether multilevel systems are fundamentally irreducible (ontological emergence).