Here, I consider Derek Parfit’s Normativity Objection to naturalist realism, according to which normative-natural property or fact reductions are “conceptually excluded”. While a lot of philosophers inclined toward non-naturalism share this view or something close to it, plenty of philosophers remain unconvinced, and the literature offers little guidance to the perplexed. I suggest a way to improve the argument – indeed, I think it is the best and perhaps only plausible way to make good on the claim of conceptual exclusion. (...) But the improved argument relies on the highly controversial claim that normative cognition is transparentin the following sense: normative concepts reveal the nature of the properties they aim to ascribe. This nature, the argument continues, is inconsistent with naturalist strictures. (shrink)