The word "ultramaterialism" has been rattling around my brain for a few weeks. I came up with this while trying to characterize the worldview of a certain class of thinker, exemplified by Minsky, Dennett, and most recently Gary Drescher in his recent book Good and Real. These people could all be called materialists or naturalists, but in some sense their mission seems to be pushing the materialist view farther than it has gone before. Minsky was one of the inventors of AI and his late work has been devoted to finding ways of breaking down minds into networks of small machines. Dennett has applied philosophical analysis to consciousness and free will, and Drescher's work in a way synthesizes the philosophical rigor and problem space of Dennett with the technical rigor of an MIT-trained engineer.
Drescher's book, which I'm still digesting, might epitiomize this tendency. In his strict mechanist worldview, there are essentially no selves, no freedom of action. The flow of time is itself illusory (we're really just embedded in an unchanging spacetime), and hence your life is not only deterministic, it's already happened.
Strictly speaking ultramaterialism is just the same as naturalism, which seems to be growing as a movement among non-academics as an "applied philosophy". So it may not make sense to introduce this a new term. But the connotation of ultramaterialism is different. Naturalism sounds rather nice and innocuous -- we think nature is rather pretty and friendly, made out of trees and scenic vistas (although this is a recent development in human history). But hardcore materialism is actually a rather disturbing philosophy. It has at least the possibility of being deeply anti-humanistic, since it holds no privileged position for persons, and doesn't believe in autonomy or moral agency.
This is not to say that the ultramaterialists are antihumanistic, or bad people. On the contrary, they are all seem like pretty decent folks, and they are making sincere efforts to preserve human values in the face of the rather pitiless mechanical universe they are exploring. But to some extent their decency is independent of their scientific thinking -- it's ungrounded, or emerges from somewhere other than their philosophy. Drescher tries to derive ethics from his pure materialism -- I don't know if he succeeds, haven't processed that part of his book yet.
The problem I see with ultramaterialism is not that it is wrong, but that it is too impractical. Say Drescher's scheme to derive morality is successful -- will it have anything to say to practical everyday ethical decisions? What about answering questions such as the morality of abortion and end-of-life decisions, which hinge on rights and what exactly counts as a person? I don't really expect that a pure materialist philosophy can say much to these questions, although I'm prepared to be proven wrong. But even if it can, it's too much work to derive ethics from complex utilitarian calculations, as opposed to the alternative of taking them from cultural institutions (like religion). Culture is a bundle of evolved heuristics, and most people, even bright people, are forced to rely on their culture for both moral principles and factual matters -- they can't really take the time to figure everything out for themselves.
While I'm not religious myself I think I can appreciate the fear that religious people get when presented with the materialist worldview, which cheerfully undermines both tradition and intuition, leaving only machinery behind. Drescher has taken on the task of reconstructing ethics in a mechanical universe, but to believe him you have to follow a fairly complicated chain of reasoning. Not only that, you have to trust that other people will follow the same reasoning, a scary and dubious prospect.
That's why I prefer my term to naturalism -- it makes it clearer that there is something radical going on here, something disturbing. I doubt it will catch on.