The purpose of this paper is to evaluate Lange’s argument in support of Sellars’ scientific realism, which, if successful, surprisingly, undermines Sellars’ scientia mensura principle and justifies the anti-Sellarsian view to the effect that certain domains of discourse which use irreducibly normative descriptions and explanations are explanatorily autonomous. It will be argued that Lange’s argument against the layer-cake view is not strictly speaking Sellarsian, since Lange interprets Sellars’ argument in an overly abstract or formal manner. Moreover, I will suggest that, (...) within a properly Sellarsian context, Lange’s argument against the layer-cake picture can actually be used for quite un- Langean purposes, namely in order to show that folk- psychological descriptions and explanations are not if fact autonomous. However, Lange could insist that his reconstruction of Sellars’ argument is substantially correct and he does have the resources to do so. I will propose that the substantial issue between Lange and Sellars turns on their different views on the function of ceteris-paribus clauses, and ultimately, on issues about the unity of science. Finally, it will be suggested that the Sellarsian framework for tackling these issues constitutes a viable alternative to Lange’s picture of theoretical explanation, while at the same time incorporating be the sound insights of the latter. (shrink)