I first want to thank John for this opportunity to present and discuss my book with the Brains readership, and for his artful shepherding of the blog in general. I don’t know how he does it, but I’m grateful that he does.
So, on to the book.
Pieces of Mind is about a problem that is not quite on the philosophical radar yet, so one hoped-for outcome of publication is to put it on the radar. Some readers here may have come across my Synthese paper, “On the proper domain of psychological predicates”, which is (nearly) the subtitle of the book. That paper is devoted to showing that “activity-referring” terms (roughly, verbs) are apt for extension to new domains in ways that “object-referring” terms (roughly, nouns) are not. (Nota bene: I’m interested in the relation between terms/predicates/concepts/verbs that are used to refer to activities/capacities/doings/operations/functions – e.g. “jump”/JUMP and jumps, rather than “cat”/CAT and cats. I will vary among these ways of referring to the symbolic relatum and its reference to avoid tedium.) I care about this issue because psychological predicates are among the verbs in their root forms. And I care about that issue because psychological verbs are being extended in the peer-reviewed scientific literature all over creation – fruit flies and plants make decisions, slime moulds and neurons have preferences, earthworms learn, bacteria converse, and so on. The uses go far beyond the belated (and to some extent still controversial) recognition of the intelligence of (say) birds and octopi. The fact of these new uses, in contexts of serious scientific discourse, yields the problem that the book raises and addresses: how should we interpret the uses across all these contexts?
The Literalist (me) holds that the new uses are literal with the same reference across human and non-human domains; the alternatives deny this. A Literal interpretation makes sense if psychology is undergoing fundamental conceptual change, a change analogous to the shifts in our concepts of physical stuff during and after the scientific innovation of the periodic table. As a way of organizing matter, the periodic table provided objective criteria for determining extensions of matter-referring predicates and instances of stuffs. It is my contention that this type of scientifically-grounded conceptual change is now happening with psychological concepts. We have begun a period of transition where traditional anthropocentric criteria for determining what counts as a real instance of a psychological capacity (and a literal use of a psychological verb) are ceding priority to objective criteria in which human capacities are special cases rather than criterial or standard for that capacity in all domains.
You can deny this by denying (implausibly) that psychological conceptual change is possible or denying (plausibly) that the concepts are in fact undergoing such change. Thus is the debate set up. The view that there is conceptual change that underwrites a difference of reference between human and non-human ascriptions is the strongest competitor to Literalism; on that view, the new uses are literal but not Literal. The other anti-Literalist positions – that ascriptions to non-humans are nonsensical or metaphorical – are considered in depth in the book and found inadequate, and will be set aside here. However, all three anti-Literalist views cleave to traditional anthropocentric psychology at least for ascriptions to humans, whereas on the Literalist view we are in the process of separating those aspects of psychological capacities that are necessary (in some non-logical sense) for having that capacity and those aspects which constitute the bells and whistles specific to their realization by human organisms. That is what the conceptual change is all about.
The Literalist position has important implications for what it means to naturalize the mind and for understanding the grounds of moral status. I discuss these implications in the book (and in work-in-progress) but will not have room to do so here. In the next blog post I will present the basic means of conceptual extension, focusing on extensions that go by way of extending mathematical models to new domains. In the third blog post I will defend the Literalist account in its basics. And in the final blog post I will consider the strongest alternative to Literalism, described briefly above, which I call the Technical-Behaviorist view.