My mistake was that I had stopped the finite regress of homunculi at least one step too early! The general run of the cells that compose our bodies are probably just willing slaves–rather like the selfless, sterile worker ants in a colony, doing stereotypic jobs and living out their lives in a relatively non-competitive (“Marxist”) environment. But brain cells — I now think — must compete vigorously in a marketplace. For what?
What could a neuron “want”? The energy and raw materials it needs to thrive–just like its unicellular eukaryote ancestors and more distant cousins, the bacteria and archaea. Neurons are robots; they are certainly not conscious in any rich sense–remember, they are eukaryotic cells, akin to yeast cells or fungi. If individual neurons are conscious then so is athlete’s foot. But neurons are, like these mindless but intentional cousins, highly competent agents in a life-or-death struggle, not in the environment between your toes, but in the demanding environment of the brain, where the victories go to those cells that can network more effectively, contribute to more influential trends at the virtual machine levels where large-scale human purposes and urges are discernible.I now think, then, that the opponent-process dynamics of emotions, and the roles they play in controlling our minds, is underpinned by an “economy” of neurochemistry that harnesses the competitive talents of individual neurons. (Note that the idea is that neurons are still good team players within the larger economy, unlike the more radically selfish cancer cells. Recalling Francois Jacob’s dictum that the dream of every cell is to become two cells, neurons vie to stay active and to be influential, but do not dream of multiplying.)Intelligent control of an animal’s behavior is still a computational process, but the neurons are “selfish neurons,” as Sebastian Seung has said, striving to maximize their intake of the different currencies of reward we have found in the brain. And what do neurons “buy” with their dopamine, their serotonin or oxytocin, etc.? Greater influence in the networks in which they participate.