British philosopher Colin McGinn, in his review of Ray Kurzweil's How to Create a Mind: The Secret of Human Thought Revealed ("Homunculism"), has some good insights into neuroscientific brain-mind studies while finding Kurzweil's book generally misleading. One error, committed by many in the neural-discussionj, is to speak of the physical brain as having agency. McGinn writes:
"Even in sober neuroscience textbooks we are routinely told that bits of the brain “process information,” “send signals,” and “receive messages”—as if this were as uncontroversial as electrical and chemical processes occurring in the brain. We need to scrutinize such talk with care. Why exactly is it thought that the brain can be described in these ways? It is a collection of biological cells like any bodily organ, much like the liver or the heart, which are not apt to be described in informational terms. It can hardly be claimed that we have observed information transmission in the brain, as we have observed certain chemicals; this is a purely theoretical description of what is going on."
McGinn agrees that there is a causal connection between brain and mind, but "mind-language" cannot be descriptive of brain-activity. "A conscious subject has knowledge, memory, perception, and the power of reason—I have various kinds of information at my disposal. No doubt I have this information because of activity in my brain, but it doesn’t follow that my brain also has such information, still less microscopic bits of it."
Neurons are not "homunculi." Neurons don't "send signals" in the way human agents send an e-mail. McGinn writes:
"The mistake is to suppose that wires and neurons are homunculi that somehow mimic human subjects in their information-processing powers; instead they are simply the causal background to genuinely informational transactions. The brain considered in itself, independently of the mind, does not process information or send signals or receive messages, any more than the heart does; people do, and the brain is the underlying mechanism that enables them to do so. It is simply false to say that one neuron literally “sends a signal” to another; what it does is engage in certain chemical and electrical activities that are causally connected to genuine informational activities."
This is a point well-taken, to be kept in mind in the discussion which is, BTW, one of the most important going on today, having ramifications in all fields (law, philosophy, ethics, theology, science, etc.).