I recently purchased the anthology Philosophy of Psychology: Contemporary Readings, edited by José Bermúdez. The first article in the collection is by Dan Dennett and it’s called “Personal and Sub-personal Levels of Explanation”.It’s a classic Dennettian paper, both in style and content. His overall goal in the paper is to defend a sharp distinction between the personal and subpersonal level of explanation. His primary example to illustrate the need for this distinction is the phenomenon of pain. For Dennett, the subpersonal level of explanation for pain is pretty obvious and straightforward: it involves a scientific account of the various neurophysiological activities triggered by afferent nerves responding to damage which would negatively affect the evolutionary fitness of an organism. The subpersonal LoE does not need to actually reference the phenomenon of “pain”. It merely explains the physical behavior of the system under the umbrella framework of evolutionary theory.
In contrast to the subpersonal LoE, the personal LoE for pain would explicitly use the word/concept “pain” in order to explain the phenomena of pain. What does this involve? The personal LoE basically involves recognizing that for the person having the pain, the pain is simply picked up on i.e. distinguished by acquaintance. If we ask a person to give a personal-level explanation of their pain, Dennett thinks that the best they can do is simply say “I just know I am in pain because I recognized that I was in pain because I had the sensation of pain because I just knew I was in pain because I was conscious of pain and I just immediately know whether I am in pain or not, and so on.” It might seem like on this LoE, there needs to be something additional, because the explanation seems to be strangely circular and nonexplanatory. Dennett thinks this is a feature, not a bug of the personal level of pain and absolutely cannot be avoided. Dennett thinks that if you are going to invoke the concept of pain at all in your explanation of a phenomenon, then you (should) automatically resign yourself that the explanation can never be in terms which violate the essential nature of the pain as being something “You just know you have” without being able to give a mechanical account of how you know it. You just know.
Dennett thinks that if we are going to use/think about the concept “pain”, then we must be ready to make a sharp distinction between these two LoE. On the subpersonal level, you need not refer to the phenomenon of pain. You simply account for the physical behavior of the system in whatever scientific vocabulary is appropriate. On the personal level, you acknowledge that the term “pain” does not directly refer to any neurophysiological mechanism. In fact, it doesn’t refer at all. It references the phenomena of “just knowing you are in pain”, in virtue of the immediate sensation of painfulness, which then produces “pain talk”. Of course, Dennett notes that we can sensibly inquire into the neural realizers for such “pain talk”, but for Dennett it is crucial to realize that on the personal LoE, pain-talk is not referential, but rather, only makes sense in terms of being the pain of a person (not a brain) who “just knows” they are in pain, when in pain.
My problem with Dennett’s sharp distinction is that he seems to too readily accept the personal level phenomena as “brute facts”, not susceptible to further levels of mechanical/functional analysis. Take pain, for example. A.D. Craig has been developing a rather interesting view of pain as a homeostatic emotion, in the same way that hunger is a homeostatic emotion. The “feelings” of pain can then be likened to the “feelings” of hunger. On this account, human pain is both a sensation (based on ascending nerve signals) and a motivation (which leads to pain avoidance behaviors). The sensory aspect of pain is clear enough, and no different from Dennett’s subpersonal account, but the motivational aspect of pain comes from the thalamocortical projections of the primate brain which provide a sensory image of the physiological condition of the body, and are more or less directly tied into limbic pathways (i.e. motivational pathways).
Crucially, this account of pain starts to provide an account of the personal feelings that go beyond an acceptance of the “brute facts” of painfulness. The “just knowing” that you are in pain is analogous to the “just knowing” that you are hungry. The interoception of homeostatic indicators is reliable since if it was not it probably wouldn’t have evolved. Just like I “just know” I am perceiving/interacting with my laptop right now, if I was in pain, I would “just know” I am in pain. This is because pain is a homeostatic emotion generated by the interoception of homeostatic indicators, just like hunger is a feeling generated by the interoception of homeostatic indicators, and the feeling of knowing the laptop is there in front me of is generated by exteroception of the actual laptop. Think about the “pain” of being cold. The regulation of temperature in the body is obviously a homeostatic process, and the process of regulation includes both a sensory component (the feeling of being cold) and a homeostatic motivational state (the motivation to do something about being cold). Pain works the same way. It has both a sensory component (which we feel), and a motivational aspect (pain leads to avoidance behaviors). And here we can start to see what a functional explanation of the personal level would look like. As Craig says,
In humans, this interoceptive cortical image engenders discriminative sensations, and it is re- represented in the middle insula and then in the right (non-dominant) anterior insula. This seems to provide a meta-representation of the state of the body that is associated with subjective awareness of the material self as a feeling (sentient) entity – that is,emotional awareness – consistent with the ideas of James and Damasio.
It seems like this “meta-representation” which generates feelings of self-hood and associated cognitive processes of a self-referential nature could lead to the feelings of personhood referenced in the personal LoE. So although we might still be able to rescue the sharpness of Dennett’s distinction between the different LoE, it seems like the distinction gets blurred and becomes unhelpful when you start talking about the meta-representational functions which give rise to the associated mental phenomena of personal level pain-feelings and pain-talk for adult human beings.