For the philosophers out there who had an aneurysm upon reading the title, just bear with me for a minute. Instead of attempting to tackle dualism using science (and thus invoking scientism to a degree that would make Sam Harris proud), I want to focus more on how naive assumptions of the interaction between mind and body can give rise to fallacious reasoning - particularly in interpretations of neuroscientific research. In other words, this is mostly going to be a rehash of articles like "Your Brain on Pseudoscience" and "The Rise of Popular Neurobollocks"; and my favourite of this genre of cranky-skeptical diatribes, an article written by Massimo Pigliucci called: "
The Mismeasure of Neuroscience".
Massimo describes the fundamental problem quite succinctly here:
Let’s begin with what exactly follows from studies showing that X has been demonstrated to have a neural correlate (where X can be moral decision making, political leanings, sexual habits, or consciousness itself). The refrain one often hears when these studies are published is that neuroscientists have “explained” X, a conclusion that is presented more like the explaining away (philosophically, the elimination) of X. You think you are making an ethical decision? Ah!, but that’s just the orbital and medial sectors of the prefrontal cortex and the superior temporal sulcus region of your brain in action. You think you are having a spiritual experience while engaging in deep prayer or meditation? Silly you, that’s just the combined action of your right medial orbitofrontal cortex, right middle temporal cortex, right inferior and superior parietal lobules, right caudate, left medial prefrontal cortex, left anterior cingulate cortex, left inferior parietal lobule, left insula, left caudate, and left brainstem (did I leave anything out?).
I could keep going, but I think you get the point. The fact is, of course, that anything at all which we experience, whether it does or does not have causal determinants in the outside world, has to be experienced through our brains. Which means that you will find neural correlates for literally everything that human beings do or think. Because that’s what the brain is for: to do stuff and think about stuff.
What he is describing here is a phenomenon known as the 'reverse inference fallacy' and this is just a specific example of "
affirming the consequent" in logic. The traditional application (or misapplication) of the reverse inference fallacy is described by Poldrack
1 who presents the argument as:
- In previous studies, when cognitive process X was assumed to be involved, brain area Z was activated
- In the current study, when task A was presented, brain area Z was activated
- Therefore, activation of brain area Z in the current study demonstrates the involvement of cognitive process X during task A.
This can also be presented as such:
- If P then Q
- Q
- Therefore, P.
The fallacious nature of the reasoning can be highlighted by inserting any everyday relationship, for example: "If it is raining, then I have an umbrella. I have an umbrella. Therefore, it is raining". This is an obviously false statement as we can think of a number of situations where (accepting the initial if-then premise) I could have an umbrella without it being raining, like if my old one had broken and I had just purchased one at a store, or maybe I'm on my way to a fancy dress party where I have donned my infamous Mary Poppins costume.
It's important to keep in mind, however, that just because the logic is fallacious, it does not mean that the conclusion is necessarily false. So even though there are possible exceptions to me having an umbrella and it being raining, it could be the case that when the argument is used, it does happen to be raining. Or, in Poldrack's example, even though it does not follow that just because cognitive process X activates brain area Z that the activation of brain area Z must implicate the involvement of cognitive process X, it could be true that cognitive process X actually is involved. I'm not sure if this coincidental correct conclusion has a fancy Latin word to describe it but I liken it to the saying that a broken clock is right twice a day; that is, the fact that the clock is broken does not justify the claim that the time it reads is definitely false, but it does justify our skepticism over the process by which it reaches the correct time twice a day.