Are intentions somewhere in your brain?

A posting that's got nothing much to do with dehumanization

I recently accepted an invitation to participate in an amazing project sponsored by the University of Granada, in Spain. It’s an exploration of “neuromyths”—incorrect beliefs about how brains work. Once it goes live in a couple of weeks the website will have links to around seventy bite-sized videos by scholars and researchers, each addressing a particular neuromyth. I contributed two videos, one on the localization of memory in the brain and the other on the question of whether beliefs, desires, and intentions are located in the brain. I thought it might be fun to expand the latter into a Substack post. So, here goes….

Suppose that you see me raise my right hand during the question and answer session following an academic talk. How would you explain this? What accounts for my right arm extending vertically?

One option—the one most likely to occur to you—is that the arm going up was caused by my intention to raise it. Breaking this down further, you hold that I desired to ask the speaker a question, and that I believed raising my hand would attract the speaker’s attention so I could ask them my question.

This sort of explanation is known as a commonsense psychological explanation. It’s the sort of explanation that we use every day to make sense of one another. But there are options other than the commonsense approach. One of them is to explain this event in neuroscientific terms, as something caused by a complex sequence of physical processes in my brain, culminating in neuron firings in my motor cortex that caused a sequence of muscle contractions resulting in my arm going up.

Both of these stories have a strong claim to being true. And that raises the question of what the relationship between them is.

Could it be that each explanation accounts for only part of what happened, and that to explain the entire event completely we’ve got to cite both of them? After all, anything that happens is likely to have a multitude of converging causes, and therefore a multitude of converging explanations. If you have a houseplant that’s doing poorly, this might be partially due the lack of fertilizer, partially due to it not enough sunlight, partially due to infection by parasites, partially due to it being watered too much or too little, and so on.

But the problem in our case is different, because each explanation of my hand going up addresses the whole event. If either of them is true, there’s no job left over for the other one to do.

The problem of coordinating neuroscientific explanations of behavior with commonsense psychological ones is NOT the same as the mind-body problem

It’s crucial to recognize that working out the relationship between the two kinds of explanation isn’t the same as working out the relationship between mind and body. The so-called mind-body problem is about the relation between two things (mind and body) or two properties (mental and physical), but the problem that I’ve just outlined concerns the relation between two kinds of explanations.¹

Putting the point a little differently, lots of philosophers nowadays believe that everything that exists is physical, and that there aren’t any spooky, non-physical entities like disembodied souls and minds. Instead, they hold that mental states are states of physical systems—paradigmatically, brain states. But even if one is a card-carrying physicalist (as I am) the problem remains of figuring out the relationship between commonsense psychological explanations and neuroscientific ones.

Option One²: One very radical strategy is to deny that commonsense psychological explanations are true. Intentions don’t exist. They are parts of a prescientific explanatory framework that needs to be replaced by neuroscience. We’re not yet in a position to do that, but we are well on the way and will eventually be in a position to dispense with commonsense explanations of behavior entirely.

From this perspective, saying that intentions cause behavior is like saying that the Storm God causes lightning, and wondering which bits of the commonsense explanation correspond to which bits of the neuroscientific explanation would be as absurd as wondering which bits of the scientific account of a lightning strike correspond to which which bits of the Storm God account!

Of course, one can hold that the commonsense framework can have pragmatic value, helping us to navigate the social world while also insisting that it misrepresents what’s really producing behavior. Although some aspects of commonsense psychological explanation might in the long run turn out to match up with what science tills us about the brain, this is very unlikely.

Option Two³: Others (probably the majority) believe that there’s some systematic relationship between commonsense psychological explanations and neuroscientific ones. The two frameworks are commensurable—that is, they map on to each other. And that means that they will prove to be intertranslatable. Once we know enough about how brains work, it will become possible to move back and forth between neurophysiological explanations and their corresponding commonsense psychological ones, so scientists could put your head in a brainoscope and read off your intentional states from your brain activity with perfect or near-perfect fidelity.

To sharpen the contrast between these two positions, lets consider how their advocates would answer the question “Are intentions located in the brain?” Those committed to Option Two would respond along the lines of, “Of course intentions are in the brain! Where else could they be located?” and add, “Once we know enough, of course we will be able to read intentions by reading brains.” Those committed to Option One disagree and say say something like, “There are no such things as beliefs, so of course beliefs aren’t located in the brain!” and add “We will never be able to read intentions by reading brains, because there aren’t any intentions to read!”

Option Three⁴: In contrast to Option One, which states that there’s no problem to be solved, and Option Two, which has it that the problem is real but solvable, the third option accepts that there’s a problem but denies that the problem can be solved.

Fans of Option Three think that the notion that intentions are located in the brain is what philosophers call a “category mistake”—a confusion between two very different kinds of ideas.

To flesh this out, it’s helpful to begin with an analogy. Imagine that you and I are on a cruise, headed to Argentina. One day, you see me standing on the deck, staring intently into the water. You ask me what I am doing, and I reply, “The captain said that we are about to cross the equator. I’ve never seen the equator, so I’m looking out for it.”

In this vignette, I’ve committed a category mistake by confusing lines of longitude and latitude with geographical features of the earth. The equator isn’t like a mountain range or a river, because it isn’t a feature of the earth. It’s not observable because it’s part of a conceptual framework—the grid of latitude and longitude—that we superimpose on the the world.  This doesn’t mean that the equator is unreal. Of course, the equator is real!  But it’s real in a very different sense than things like mountains and rivers are real.

According to Option Three, the concepts that we use to make sense of our own and others’ behavior—concepts like belief, desire, and intention—are like lines of longitude and latitude. They are part of a conceptual framework of immense practical value that allows us to navigate the social world (just as latitude and longitude allow us to navigate the globe). Intentions aren’t located in the central nervous system any more than the equator is located in (or on) the earth.

Neuroscientists tell us what is in the central nervous system. Their list includes neurons, glial cells, neuromodulators, and the like, but the list does not include intentions.

The two explanatory frameworks are so systematically different that they are not intertranslatable. They are also wildly different methodologically. The neuroscientist wishing to explain what caused my hand to go up does so by monitoring neuron firings in my brain and tracing out their causal trajectories. But when you’re interpreting the same thing commonsensically, you don’t observe or discover that my intentions bring about my behavior. Rather, you assume that I do the things that I do because I have reason to do them. You try to fit my behavior into a coherent, rational framework. And if that doesn’t work—for instance, if I raise my hand but never ask a question—you revise your explanation by attributing a different set beliefs or desires to me to fit my behavior into some other rational pattern.

Unlike many philosophical problems, this one has real implications for how scientific research is conducted. The option that a neuropsychologist adopts will make a difference to the research questions that they ask and attempt to answer.

I guess it’s apparent that I prefer Option Three to its alternatives. I wonder which of them readers of this Substack gravitate towards.

1. The philosopher José Luis Bermúdez calls this the “interface problem.”

2. In philosophy jargon, this is called “eliminative materialism.”

3. I’m painting with a broad brush. This category of responses includes type identity theory, various versions of functionalism, and the representational theory of mind. These are all theories that, at a more granular level, are incompatible with one another. But they all share something in common: namely, the idea that neuroscience and commonsense psychology can enjoy a happy marraige.

4. Philosophy of Mind mavens will recognize that this is basically Donald Davidson’s position in his argument for anomalous monism.