Externalists reason that there is more to the mind than head-based functionalist information processing. Such processing must be analyzed along with environmental relations. I term this approach “envirofunctionalism.” For externalists, the problem with functionalism is not a lack of essential ties to particulars of biology or any physical structure, but limited scope. The arguments of Chalmers, Clark, Putnam, and Burge against internalism convinced most philosophers that the mind cannot be found entirely within the scope of the brain—we must bring in environmental relations to understand meaning. We can think of this larger scope as envirofunctional- ism. However, it is unclear how envirofunctionalist accounts could adequately explain consciousness. Think of the replicant example discussed by Noe. Noe regards it as an empirical question whether a robot with a digital computer brain could be conscious or not. There are no success criteria other than how the robot functions—functionalism is not judged by other standards.
Functionalism is detached from the particulars of physics. In a functionalist account, there are no brain correlates of consciousness because functionalism is relationally defined and correlates are physical. So tests for consciousness from a functionalist perspective cannot be about physical processes or structures. That is why Noe redefines neurobiology as a functional notion. If neurobiology had genuine biological causal powers of consciousness, then it would be problematic for the functionalist. Then consciousness could not be given an adequate functionalist explication. It is true that №ё takes on an embodied externalist perspective, which involves interaction between a robot and the world, but this interaction is described in terms of structures whose physical realization is incidental. The robot might contain hydraulics, steel, and so forth—we don’t know. The environment could be something other than earthly. Functionalism lacks physical criteria for mind and consciousness, and №ё^ envirofunctionalist version of functionalism adds none. The same goes for externalism generally. Externalism extends functionalism with abstract causal relations while preserving its formal nature—it is functionalism in and beyond the skull. At the beginning of this book, I asked if the conceptual mind could solve the problem of consciousness. At a scientific level of analysis, I think it can but not through functionalism, whether environmentally scoped or not. Abstract characterization of functional organization, processes, and behavior is insufficient. The philosophical temptation has been to remain at an abstract conceptual level, but we need to know what physically causes experience. This is the task of brain science.