Peter Hankins from the wonderful site Conscious Entities just posted a short review of Alva Noë’s latest book, Out of Our Heads. Peter is skeptical of Noë’s claim that we are not just our brains. My response is in the comments, which I reproduce here:
As someone very sympathetic to Noe, let me attempt a defense of his claim that the mind is “out of the head” and that it is not just the brain which is important to consciousness, but rather, the joint brain-Earth interaction.
First, in regards to agency, Noe takes his cue from Varela and Maturana’s theory of autopoietic systems. Autopoietic theory says that the unicellular organism is the root of all mind because (1) we evolved from unicellular organisms and (2) our ontogenetic history starts as a unicellular organism. Accordingly, Noe defines agency in terms of the self-regulating, goal-directed autonomy demonstrated by these autopoietic systems. Organisms are said to be “structurally coupled” with the environment. While sure, this might not be agency *qua* agency insofar as it is not metacognitive, there are reasonable grounds to suppose that autonomous goal-directed behavior can support a “minimal” sense of agency. Accordingly, when Noe claims that bacteria are conscious, one must keep in mind a distinction (which he, unfortunately, does not draw) between primary consciousness and secondary consciousness (metacognition, introspection, etc). Noe’s claims become a lot less radical when you realize his theory of “enaction” is only really applicable as an explanation of primary consciousness, not secondary consciousness.
Second, in regards his claim about the brain not being sufficient for consciousness, let me explain. If we accept the basic teleological nature of organsisms, then we can say that brains evolved to react to entities in the real world (in accordance with their internal needs/interests). We can say that brains are intentionally directed towards the real world insofar as information necessary for surviving is to be found “out there”, in the world. So primary consciousness is directed at the world because this is how survival works: we seek stimulus-information for the control and guidance of behavior. This grounds Noe’s claim about the brain being necessary but not sufficient for mind in at least two ways. First, we could not imagine an organism without an environment. Organisms, by definition, evolve in environments. And whereas the environment does not need the organism to exist, the organism needs the environment to exist. Second, the brain is not sufficient for consciousness because he defines the brain’s teleological “purpose” as attending towards information in the environment. This is where Noe takes his cue from J.J. Gibson’s theory of ecological optics.
This is also the crucial point of the Ferret experiments. The experiments don’t show that the brain is not important for consciousness. What they show is that the brain evolved so as to be directed at stable environmental invariants (which lead to invariant patterns of stimulus). This is the essence of the ecological thesis that Noe defends. Take away the world, and the brain has nothing to “resonate” to, in Gibson’s terms. For this reason, the brain is not sufficient for primary consciousness. Accepting this thesis doesn’t imply that the brain is unimportant to consciousness. On the contrary, it merely seeks to demonstrate the essential purpose of the brain: to be directed towards the world, not create an inner 3D model of it. Here, Noe borrows from Rodney Brooks is accepting that “the world is its own best model.”