Remind Physicalists They're Physicalists

I think that 'with neuroscience' explanations, and brain scan images in particular, are more satisfying because they remind us we're physicalists.

I don't see how you're justified in thinking that. It's too detailed a hypothesis to locate using that data.

I think you're reading too much speculative detail into this. Is it any different from persuading people to buy your drugs by showing men in white coats and saying "studies have shown"?

One angle here (which you seem to implicitly advocate?) is that including pictures of brains and talking about brain components causes people to change their minds about cognitive/philosophical matters in specific directions. If the results of that exposure are positive then it seems like it might be a good PR strategy, with interesting pedagogical applications if you were trying teach certain lessons from psychology in a vivid and convincing way.

On the other hand it also seems that the effects could be explained by certain kinds of priming mixed with the representativeness heuristic rather than detailed evidence in support of the precise claims that are being made. That is to say: its not clear to me that this phenomena might not be a good way to explain things so much as a "physical brain fallacy" (roughly: just because the brain is physical, doesn't mean a particular claim about cognitive processes is true).

Imagine a control group who get a sales pitch (for a bad product) telling them that they should rationally calculate that it would fulfill their desires and make them happier to buy and use. The experimental group could get roughly the same pitch (for the same bad product) except their emotional reactions would be additionally described with reference to dopamine receptors and modulation of the amygdala and so on. If talking about the brain causes people to think the pitch is better and to buy a bad product it would be a bad thing rather than a good thing.

Having read the linked articles and knowing more about their details than me, does the inclusion of "brain talk" seem to function more like a fallacious trick or more like evidence? Does it look like the rhetorical technique can be used generically, or only to increase people's beliefs in things are probably true, related to neurological facts, and that they were already refusing to accept due to some philosophical/emotional confusion having to do with the physicality of the brain?

A simple explanation is that using phrases like "brain scans indicate" and including brain scan images signals scientific eliteness, and halo effect/ordinary reasoning causes them to increase their estimate of the quality of the reasoning they see.

I've decided to upvote your article for presenting a concise summary of this topic and also, very importantly, including links to the full pdfs of the academic articles Weisberg et al. (2008) and McCabe & Castel (2008) which you used to support your argument. This is not always possible, but I think is always to be commended when it is.

However, having now read both of these articles in their entirety, I would like to point out what I believe to be an important omission in your summary of the Weisberg et al. (2008) article.

First, you state:

And yet, Yale cognitive science students rated the 'with neuroscience' explanations as more satisfying than the regular explanations.

You also state:

Somehow I suspect people who chose to study cognition as information processing are less likely than average to believe the mind runs on magic.

You conclude with:

Sometimes even physicalists need to be reminded — with concrete reductionistic details — that they are physicalists.

However, I obtain an entirely different conclusion from this article. First, I shall summarize what I believe to be the salient points of Weisberg et al. (2008):

• Novices (ie. those who had not chosen to study neuroscience), found good explanations satisfying and bad explanations to be unimpressive. Add useless neuroscience and what happens? Good explanations remained pretty much just as good but bad explanations suddenly looked a whole lot better. As stated in the article:

Post hoc tests revealed that although the ratings for good explanations were not different without neuroscience (M = 0.86, SE = 0.11) than with neuroscience (M = 0.90, SE = 0.16), ratings for bad explanations were significantly lower for explanations without neuroscience (M = −0.73, SE = 0.14) than explanations with neuroscience (M = 0.16, SE = 0.16)

• Sadly, students who chose to study neuroscience were only impressed if given explanations actually containing neuroscience, despite the fact that these additional frills were worthless:

Unlike the novices, the students judged that both good explanations and bad explanations were significantly more satisfying when they contained neuroscience, but the bad explanations were judged to have improved more dramatically, based on a comparison of the differences in ratings between explanations with and without neuroscience [t(21) = 2.98, p < .01]

• Thankfully, neuroscience experts were not fooled. Bad explanations were still rated as bad. Also, the good explanations were rated as worse when the neuroscience information was included:

Good explanations with neuroscience (M = −0.22, SE = 0.21) were rated as significantly less satisfying than good explanations without neuroscience [M = 0.41, SE = 0.13; F(1, 46) = 8.5, p < .01]. There was no change in ratings for the bad explanations (without neuroscience M = −1.07, SE = 0.19; with neuroscience M = −0.87, SE = 0.21).

I think the problem is not that the neuroscience students needed to be reminded that the mind does not run on magic. I would instead say that they give too much value to the explanatory power of neuroscience, even when superior explanations exist. I do not think this is surprising given that these are people who are: a.) fairly untrained and b.) have chosen to study neuroscience, and therefore are more likely than the general population to have a highly favorable impression of it.

The conclusion I would draw from this article is that irrelevant neuroscience information should generally not be included unless you feel your argument is shoddy and your main intent is to convince novices that you are right. Only neuroscience students are more impressed with the addition of useless neuroscience in any explanation, and they are presumably not a large portion of the general population. I am certainly not confident that this result can be generalized to anyone with any passing interest in neuroscience, or anyone who wants to be a rationalist. Also, neuroscience experts will really not be impressed with the addition of such irrelevant frills. This says to me that the best way to promote the proper understanding of the way our minds work is to never include neuroscience information unless it logically adds value to an argument and to train students in specialized fields like neuroscience to value logic above the appearance of something being about neuroscience. Apparently, this happens already, since experts seem to hate the useless neuroscience information so badly that it taints even the good explanations in their eyes.

In regards to McCabe & Castel (2008), I wonder if people simply feel the concrete brain image is more comprehensible to them that the abstract graphs (both the simple and complex ones). It may even be that it takes them less time to understand the intent of the brain scan images because of this, therefore they like them better. I wonder if other images that also concretely demonstrate an effect would be rated higher than ones that don't. Also, perhaps the brain information is preferred because it conveys more information than the bar graph and but is also easier to grasp than the complex graph.

But these are Yale cognitive science students. Surely they don't think the mind runs on magic, right?

Wow. I had no idea Yale cognitive science students had reached the astronomical level of competence where we ought to be surprised when they make simple mistakes. I assume that none of them are religious, either?

I have another possible explanation, which I think deserves a far greater "probability mass'': images make scientific articles seem more plausible for (some of) the same reasons they make advertising or magazine articles seem more plausible -- i.e., precognitive reasons which may have little to do with the articles' content being scientific. McCabe and Castel don't control for this, but it is somewhat supported by their comparison of their study with Weisberg's:

The simple addition of cognitive neuroscience explanations may affect people’s conscious deliberation about the quality of scientific explanations, whereas the brain images may influence a less consciously controlled aspect of ratings in the current experiments.

"-Scientific content, -scientific images" includes most advertising, which is pretty obviously made more convincing through images. For an example of "+scientific content, -scientific images", think of the many articles in (say) New Scientist that are made more pleasant (and quite possibly more convincing) by more-or-less purely aesthetic graphics.

I can also think of some "less consciously controlled" reasons that are science-specific. Images of brain scans lend a kind of "hard science" sheen to the articles' claims -- in much the same way that CGI molecules spinning around hair follicles add to shampoo advertising's claims of sheen ("-scientific content, +scientific images"). McCabe & Castel again:

This sort of visual evidence of physical systems at work, which is typical of ‘‘harder’’ sciences like physics and chemistry, is not typically apparent in studies of cognition, where the evidence for cognitive processes is indirect, by nature. Indeed, it is important to note that while brain images give the appearance of direct measurement of the physical substrate of cognitive processes, techniques like fMRI measure changes in relative oxygenation of blood in regions of the brain, which is also indirect. Of course, it is unlikely that this subtlety is appreciated by lay readers.

In other words, images of brain scans create the impression that underlying physical mechanisms are better understood than they actually are. This is also an issue in pop science reporting:

[...] many cognitive neuroscientists have expressed frustration at what they see as the oversimplification of their data, and have suggested that efforts be made to influence media coverage of brain imaging research to include discussion of the limitations of fMRI, in order to reduce the misrepresentation of these data.

So how does this study pertain to physicalism? As I see it, this study underscores the ease with which intelligent people -- including physicalists -- can be fooled into thinking that scientific studies explain more than they do by the use of overly-concrete, hard-science-flavored imagery (and language). It shows how easy it is to jump from an image of a presumed physical substrate for some phenomenon to the belief that we better-understand that phenomenon. In other words, it shows how the impression of reductionism can function as a curiosity-stopper.

As I understand it, that is a common criticism of reductionism in practice.

Also, this is why I'm uncomfortable with the overuse of overly-precise terms from maths and science -- like referring to one's own "probability mass" on Less Wrong, or the Churchlands bemoaning their "seratonin levels" rather than saying they feel horrible (see here, p. 69). Sometimes an unwarranted science-y aesthetic can mislead.

Is it a fair restatement to note that people (physicalists included) get quite different priming effects from 'mind' and 'brain'? The first makes us think of our subjective experience, the second makes us think of a physical object.

I've certainly noticed that reductionist arguments are more convincing to others when I use 'brain' in place of 'mind'.

Here's a piece of supporting evidence for your theory: http://www.economist.com/node/21526321

In particular, the second study. There were four statements of a patient's condition after a traumatic injury: 1) David is healthy and fully recovered. 2) David passed away. 3) David died, was embalmed at the morgue, and is now in the cemetery, in a coffin, underground. 4) David is in a persistent vegetative state.

Group A rated the cognitive function on options 1, 2, and 4. Group B rated the cognitive function on options 1, 3, and 4. Non-religious folks - i.e., materialists - did not rate 2 and 3 equally relative to 4. It seems reasonable to conclude that the more detailed phrasing of option 3 "reminded them" to look at the situation from a materialist perspective.

Of course not all libertarianism is "contra causal",and of course complete physical determinism isn't a fact

On the subject of acausal free will, I wonder if it is simply a misinterpretation of the benefits that we can gain through our choices. While we don't have free will in the sense of our choices being uncaused, we do have more choices available to us, than say, a cow or a spider. So we have the freedom to choose better, even if not the freedom to choose whatever. So here I am hypothesizing that people interpret greater intelligence as greater acausal free will.

Cognitive scientists share a number of basic assumptions... the most fundamental driving assumption of cognitive science is that minds are information processors... Almost all cognitive scientists are convinced that in some fundamental sense the mind just is the brain.... Few, if any, cognitive scientists are dualists, who think that the mind and the brain are two separate and distinct things.

Bermudez, Cognitive Science, page 6.

Thank you for the button-pressing report. I've been looking for something like that for a while. (Well, by "looking" I probably mean "sort of wishing I'd accidentally stumble upon it.")

Nice, modulo Christina's comment below. But, I wouldn't place any stock in time-delay button-pressing experiments. They are only suprising if you both a) believe in free will, AND b) believe that the freely-willed action, and the conscious experience of making that decision, must be simultaneous.

There is no reason to expect this, and many reasons to expect it not to be the case, even if you believe in free will. I don't know if it's even meaningful to ask "when" a perception occurred - your brain may present you with a percept, and backdate it or forward-date it.

It's just that physicalists take the controlled and repeated findings of physics and neuroscience as being stronger evidence than their own subjective experience is.

This is not a straightforward matter. There are people who deny the existence of colors, of time, of any sort of will, or any sort of subjective experience, on the basis of "physicalism" or "science". Physics and neuroscience actually contain no such thing as "subjective experience". Do you therefore conclude that there is no such thing at all? No, you believe it's there and it has a semi-obscure relationship to the physical facts, and you use what you hear from science to adjust your beliefs about the nature of that relationship, and also to adjust your attitude towards the naive beliefs that arise naturally from your experience.

What's actually going on in the minds of people who make private attitude adjustments in order to be good little physicalists, is itself best described as a subjective process. The complex of beliefs peculiar to this site, as recently summarized in the Gospel According to Zed, are a great case study in such self-shaping of subjectivity. It's subjectively experienced, it's subjectively willed, and it's done in response to a subjectively imagined idea of what Science is saying. This is true both for the more spectacular ontological commitments that people make and break, and for the epistemological adjustments performed in response to the psychological demonstration of fallibility of judgment. And I'd say it usually has about as much basis as the belief of someone who thinks there is a gay gene because they remember hearing about it on TV. Science can be wrong, the popular description of what science says can be wrong, and the private implications that a person draws from this can be wrong.

"Okay. Now, think about the physical state of the entire universe one moment before you decided to say "Right" instead of something else, or instead of just nodding your head. If all those atoms, including the atoms in your brain, have to move to their next spot according to physical law, then could you have said anything else than what you did say in the next moment?"

The world can branch in a moment, so the answer should be "yes".