Brain Lessons (Pt. III)

In her book Seven and a Half Lessons about the Brain neuroscientist Lisa Feldman Barrett makes a number of statements that evoke interesting questions, and although the author doesn't delve too deeply into those questions, we've looked at a couple of them in Parts I and II of this series titled Brain Lessons. In this final post on her book we'll look at some of the implications of these two statements:

"...there's also increased activity in the brain system that controls heart rate, breathing, metabolism, the immune system, hormones, and other internal junk and gunk...all from processing the meaning of words!" p.89

Living in an environment of continual nastiness is harmful to humans because "words can physically injure your brain." p.92

Of course, it's not the words themselves which produce changes in the brain, but rather the meaning of those words that's harmful.

One philosophical school of thought, called materialism, states that everything that exists consists of material stuff, there are no entities, such as immaterial minds, that cannot be reduced to matter. Another school of thought, we'll call this dualism although that probably oversimplifies, posits that in addition to a material brain we are also possessed of an immaterial mind, or soul, and that the two somehow interact with each other to produce the everyday experiences of our lives.

Materialists scoff at this notion, demanding of the dualist an explanation of the means by which two fundamentally disparate substances could interact with each other. This is called the interaction problem and it's said to be the major challenge to belief in the existence of immaterial minds. Yet the challenge seems a bit beside the point. Whether or not the dualist can explain how two disparate substances interact it seems obvious that the material and the immaterial do interact all the time, and Barrett's statements give us an example.

If the "meaning of words" produces changes in heart rate, breathing and all the rest then isn't that an example of something immaterial, information, causing an effect in something material, the body? And doesn't this sort of thing happen continuously throughout a person's life? The sensation of pain or of color is not material or physical, indeed we don't know what sensations actually are, but we do know they're elicited by material or physical stimuli. So are the sensations of sound, flavor, warmth and odor.

And if every moment we witness immaterial sensations being produced by material stimuli then one of the chief objections to dualism seems to lose its force.

Barrett acknowledges the mystery in this, but then she makes an apparent (in my opinion) misstep. She writes: "...this transformation from physical signals to mental feelings remains one of the great mysteries of consciousness." True enough, but then she adds, "It also reaffirms that your body is part of your mind ...in a tangible, biological way."p.107

I'm not sure what she means by this, but she seems to be implying that the mind is a biological entity or that it's in some sense reducible to the material stuff that biologists study. If that's what she's claiming then I'd have to ask her how the transformation from the physical to the mental (or vice-versa) "reaffirms" that the body and the mind are the same substance.

It's not clear to me that the fact that physical and the mental can interact affirms that they're the same substance at all unless one assumes a priori that physical substances can only interact with other physical substances. But, as I've argued above, this seems at least questionable. The meaning of a word is not a physical thing, but, as Barrett points out, it can have physical effects.

What could just as easily follow from her examples is not that "your body is part of your mind ...in a tangible, biological way," but rather that body and mind, though distinctly different substances, are somehow integrated so that each can affect the other.

Exactly how they're integrated is the "great mystery" of which she speaks. A Nobel Prize awaits the person who unlocks the mystery.

Why does any of this matter? It matters because ideas matter, they have consequences and implications. If materialism is true then a number of things become much harder to believe. Here are a few:

1. If all we are is a material, physical body it becomes much harder to believe in free will, and if we don't believe we have free will, it's much harder to believe that we have moral obligation, moral responsibility or human dignity. If our choices are not in some sense free then punishment and reward are never deserved and guilt and regret make no sense.
2. If all we are is a material, physical body it becomes much harder to believe that there's anything about us that survives our physical death.
3. If matter is all there is then not only is there no immaterial mind or soul, there's also, quite likely, no immaterial God.

Whether or not you think those implications are important is for you to decide.