He does not so much attempt to prove that materialism is right (although he presents his 'Causal argument' for it in the first chapter) as analyse why dualism seems intuitively plausible.
Although Papineau recognises that it is possible to reject these premisses, he claims that to do so leads to empirically implausible conclusions.
Our concept of red includes a 'faint copy' of red, whereas our conception of the human perceptual system includes no such faint copy.
Susan Blackmore characterized Papineau's book as "definitely written for philosophers rather than psychologists or neuroscientists" because of its focus on abstruse philosophical arguments.
She concludes that "Papineau has helped explain why" it's so easy for us to think there's an explanatory gap for consciousness, though she doubts that Papineau's insistence that consciousness is an inherently vague concept will dampen neuroscientific efforts to understand it better.