David Chalmers’ ‘conceivability’ argument against physicalism is perhaps the most widely discussed and controversial argument in contemporary philosophy of mind. Recently, several thinkers have suggested a novel response to this argument, which employs the ‘powerful qualities’ ontology of properties. In this paper, I argue that this response fails because it presupposes an implausible account of the physical/phenomenal distinction. In the course of establishing this, I discuss the so-called ‘ultimate’ argument for the claim that dispositional properties form the subject matter of physics. I argue that the ultimate argument can be interpreted in a strong or a weak way, and that the strong interpretation is implausible. I argue that this undermines the powerful qualities based response to the conceivability argument. I also argue for a general conclusion: that we should not define ‘the physical’ exclusively in terms of a distinction drawn from ontology.