Descriptive metaphysics investigates our naïve ontology as this is articulated in the content of our perception or of our pre-reflective thought about the world. But is access to such content reliable? Sceptics about the standard modes of access (introspection, or language-driven intuitions) may think that investigations in descriptive metaphysics can be aided by the controlled findings of cognitive science. Cognitive scientists have studied a promising range of representational advantages, that is, ways in which cognition favours one type of entity over another. The notion of representational advantage is investigated and some scepticism is expressed as to its appropriateness for use in descriptive metaphysics.