I have tried to show that the principal contemporary forms of materialism are, despite their intellectual sophistication, quite hopeless. However, this essay is not just a survey of heterogeneous philosophical arguments whose only common feature is that they are fashionable and support physicalism. Their connexion is deeper and more systematic.

It is impossible to prove a priori that no form of materialism could work. Or perhaps that was proved right at the outset: the argument in the second section of chapter 1 is a perfectly general reason why no materialist theory could be adequate. The materialist theories are all more or less ad hoc ways of avoiding this knock-down argument. It is unreasonable to expect anyone to provide a further argument to show that all possible ad hoc evasions of the basic argument must be false. Nevertheless, the materialist strategies are systematically related. Given that it is subjectivity that poses the problems for the physicalist, there are only three options open to him. He might deny that subjectivity as normally understood poses any problem for materialism: he might provide a reductive analysis of it in physicalist or topic-neutral terms, or he might deny that it exists. We have discussed all these strategies in (I hope) their most sophisticated forms. It is true that I have not tried to prove that a new variant on these basic strategies could not be developed, but I cannot see what it could be. Any non-reductive theory which is materialist enough to preserve mechanism must lead to epiphenomenalism, as argued in chapter 1.