Monday, August 22, 2011

More panadaptationism: cognitive biases

Someone sent me a link to a NY Times article called "Reason Seen More as Weapon Than Path to Truth".  (The age of the article tells you something about how long these ideas sit in my draft bin.)  It's about "argumentative theory", which claims that human reasoning evolved to win arguments, rather than to reach truth.  In this view, even our many cognitive biases are adaptations to improve debate skills.  This goes against the more common view that cognitive biases represent limitations of natural selection.

Given these two diverging views, I was curious about the evidence for each side.  But I was disappointed in how little evidence the article presented.  In fact, it presented no evidence at all!  I've decided the article is a self-referential parody.

The article instead talks about how resilient cognitive biases are. 
Mr. Mercier, a post-doctoral fellow at the University of Pennsylvania, contends that attempts to rid people of biases have failed because reasoning does exactly what it is supposed to do: help win an argument.
If cognitive biases are adaptive this does not imply that they are harder to be rid of.  If cognitive biases represent limitations of evolution, this does not imply that they are easier to be rid of.
“People have been trying to reform something that works perfectly well,” he said, “as if they had decided that hands were made for walking and that everybody should be taught that.”
Never mind that no evidence has been put forward for argumentative theory, let's march onwards to even more questionable conclusions!  In this case, the inference is that if we're adapted for something, we better not mess with what nature wants.

Later, the article gets into the political implications of argumentative theory.
Because “individual reasoning mechanisms work best when used to produce and evaluate arguments during a public deliberation,” Mr. Mercier and Ms. Landemore, as a practical matter, endorse the theory of deliberative democracy...
I'm not sure what this has to do with argumentative theory at all, but then, we don't even know whether argumentative theory is true or not, so what does it matter?

The NY Times article does cite its original source, which is a hundred-page paper in Behavioral and Brain Sciences.  I not willing to read this paper, so I will remain agnostic as to whether the lack of evidence is NY Times' fault, or the scientists' fault.  However, my boyfriend was trying to read the paper earlier, and said it was merely a review of evidence for cognitive biases, without any evidence that these are adaptive.  There is additional hearsay from Massimo Pigliucci, who says, "The first substantive thing to notice about the paper is that there isn’t a single new datum to back up the central hypothesis."

I could write a rant about panadaptationism, but then it's not like these rants are in short supply.

7 comments:

miller said...

Somehow in writing this, I forgot that I've written about it before! I hope it is not too redundant.

Joshua Lord said...

I haven't read the entire paper either but from what I understand it is a theoretical paper arguing that existing data on reasoning and cognitive biases are better explained by this new "argumentative" theory than existing theories. Of course, empirical testing of the theory is needed before any firm conclusions can be draw but the main purpose of any theoretical paper is to provide the impetus for further investigation. It is plenty enough work to devise a novel theory capable of explaining a vast quantity of previous research findings without having to design and conduct several experiments also. I'm sure there are many researchers currently brimming with excitement at the prospect of doing this, however, so let's see how this new theory holds up against empirical scrutiny in the years to come.

miller said...

Joshua Lord,

That is one possible defense that I discussed in a more recent post. For these researchers, it seems adaptationism is simply a starting point. So when they advance adaptive theories, it's not because they necessarily think the adaptive theories are correct, it's because they're trying to encourage and set the stage for more research.

Of course, if that is the paper's defense, then we must grant a few things: 1) The paper should be tentative about its own conclusions and not claim to have evidence. 2) NY Times should not take seriously the paper's conclusions. 3) I should not take seriously the paper's conclusions.

I also do not agree with the paper's argument that existing data is better explained by argumentative theory. The existence of cognitive biases does not show that biases lead to persuasiveness, much less that persuasiveness is an adaptive trait.

More generally, we can question the efficacy of the "adaptationism as starting point" practice. Evolutionary biologists tend to use adaptation as a last resort explanation.

Joshua Lord said...

OK, after reading your more recent post I think I better understand you reservations about this paper.

First of all (after a quick skim read) I can confirm that the authors fail to establish the case that persuasiveness is fitness enhancing - which is a fairly lamentable failure on their part seeing as it is a foundational assumption of their theory. Furthermore, they don't take into account other plausible adaptive explanations for cognitive biases and probably overstate the extent to which previous research supports their theory. Also, I acknowledge the scientific questionability of devising a theory ad hoc to fit existing evidence.

Perhaps the authors should have been a bit more conservative in the scope of their claims. However, I can't blame them for seizing the opportunity to disseminate their ideas to a far greater audience via the NYT, thus raising their own profile and the profile of their research. Hopefully most readers of the NYT are sufficiently scientifically literate to not accept the validity of this theory uncritically.

By the way, I'm interested in the idea of using "adaptiveness as a last resort" when explaining phenotypic characteristics. I'm aware of spandrels and exapation but didn't realise that adaptiveness is generally considered the least likely explanation for phenotypic characteristics. I've always considered adaptiveness to be a good starting point when considering evolutionary origins, especially when it is so easy to see fitness enhancing effects of phenotypic. I would have thought that something as profoundly impactful on human behaviour as reasoning would be subject to myriad selection pressures. In fact, it seems likely that reasoning has evolved to serve many functions, such as persuasion but also reaching accurate conclusions and maintaining social bonds. Perhaps SOME aspects do not serve an adaptive purpose but in general I would contend that adaptiveness is a reasonable starting point when considering the evolutionary origins of reasoning and other impactful and cross-cultural psychological abilities/traits.

miller said...

Joshua Lord,
I agree with your point about the researchers seizing the NY Times opportunity. I think I'd do the same thing.

I'm not exactly sure why adaptation is seen as a "last resort explanation" in current evolutionary research. That is, I've heard lots of explanations from other people, but I would only be able to repeat those explanations. Here's one account I once read. It seems to be a recent development in the last few decades, and evolutionary biologists seem to think it's a lesson learned from past mistakes.

Joshua Lord said...

Thanks for the link. I'll certainly be more sceptical of evolutionary explanations for psychological traits that I hear in the future. I think it's VERY easy to get carried away with appealing stories. It takes a disciplined mind to resist this innate tendency toward narrative-induced credulity and withhold judgement before the evidence is in. I'd like to think that my critical thinking skills are fairly advanced but I'll admit that when I first become exposed to the argumentative theory of reasoning I assigned it's veracity a far higher likelihood-ratio than is warranted by the evidence. Upon reflection, I can see that I was positively disposed to credit the idea because of my preference for counter-intuitive (or at least non-obvious) explanations for ostensibly straight-forward phenomena. Reading your own views and the views of others who've commented on this blog has made me cognizant of this lapse in critical thinking. I hope that you can take some satisfaction in knowing that you have successfully promoted healthy scepticism in at least one person via your blog! :)

By the way, here is an essay that I suspect represents the other side of the debate on the scientific merit of evolutionary psychology rather well. I really think that you'd find it enlightening, as I did!

miller said...

I think it's reasonable to initially trust the claims made by evopsych. It is, after all, a field of science that I, as a non-expert, do not fully understand. It's only after investigation that I come to distrust it, at least in its current state.