Galen Strawson revisits Frank Jackson’s thought experiment in a final draft made available here. For those not familiar with this thought experiment, Galen sets it up quickly and clearly.
If this line of thought is right, the mistake on both sides is—to repeat—to confuse materialism or physicalism with physics-alism. The mistake is a mistake whether it leads materialists to deny a certain truth (Mary learns something completely new about the nature of concrete reality, and hence, if materialism is true, about the nature of physical reality) or whether it leads those who reject materialism to beg the question against materialism. It is a distinctively twentieth- and twenty-first-century mistake.