In Part I of this book, I examined many versions of materialism and found them wanting. Some of them cannot be demonstrated to be false, but they fail to be good theories for other reasons, such as vacuity, unjustified skepticism, introduction of special terms that are not known to be naturalistically definable, and failure to provide advertised explanatory value. It is not good intellectual practice, scientific or otherwise, to give our assent to views that have such grievous faults.

“Materialism” suggests naturalism and respect for science. There is thus some danger that the claim that phenomenal consciousness is material will carry with it the suggestion that it has been brought safely within the orbit of scientific explanation. Since that is very far from being the case, it would be better not to suggest it. It would be better to record the existence of an explanatory gap in a terminology that keeps that fact clearly before our minds. We should say that dualism is our best theory, because we cannot plausibly deny phenomenal consciousness and we cannot give an account of it within our sciences. We know what it is to give a materialist account of life, and we have very promising ideas for further research on purely materialist theories about how our brains make us intelligent. But we do not have any comparable account of or research program about phenomenal consciousness.