A blog about problems in the field of psychology and attempts to fix them.

Thursday, March 15, 2012

Design, and why we should and shouldn't care about deep theory

Bjoern Bremb, who guy who gave the very cool research talk at WCALB, linked to a good essay on his own blog where he argues that we should banish the term 'design' from our discussions of evolution. I started responding to his comment, but before I knew it, enough was written, and the subject had shifted enough, to justify another post. I appreciate the desire to banish 'design'. I used to hold that view myself, and I think it is a much better position than using the term sloppily. That said, I am now convinced that the current way we discuss evolutionary theory has some deep problems, and that many of those problems could be solved through a fight to reclaim the concept of design. Alas, I'm less convinced that most people should care, e.g., that the work of the day-to-day biologist or psychologist is being negatively impacted by their vague commitment to a problematic version of evolutionary theory. This will not be quite as articulate as I would like, but I will try to explain, in a roundabout way:

<a href = http://www.gvsu.edu/psychology/joel-quamme-164.htm>Joel Quamme</a> is a friend of mine who does cognitive research ranging from behavioral measures of recognition to testing still-experimental methods for analyzing whole-brain activation in MRI data. Joel is perfectly adept at philosophical conversations, and can defend the cognitive approach as well as anyone I know, but at some point he usually says to me "Look, this is all fine and good, but there are concrete questions regarding how memory works, and I am trying to answer them." It is pretty much a conversation killer, because he is right. Most people can go about doing their research without worrying in the slightest about the coherence of the deep theory.*

In the same way, it is completely true that most working biologists are not hampered in their day-to-day research activities by the problems in their underlying theory. At the end of the day, there are concrete questions regarding how particular biological systems work, and the theory of evolution is pretty far removed from the task of determining how specific systems work. Bjoern's work, at the edge of psychology and biology, is a good example of this. Inconsistencies in the deep recesses of an otherwise serviceable version of evolutionary theory pose so little impediment, that it is worth noting that the same work could be done perfectly well by someone who does not believe in evolution. The theory is simply irrelevant.

So here is the problem: As I said above, I think evolutionary theory without design is better than evolutionary theory with a sloppy talk about design, and I've said that the the theory is pretty much irrelevant to most people's work. So why should anyone care?

The only good reason I can give is that we want our theories to have explanatory value, and we want the explanatory value to be clear. This is a pure value judgment, at least as laid out here, but one to which I think most scientists would ascribe. Modern evolutionary theory is in crisis. It is a crisis that some people realize, and there are efforts at a solution. The crisis is that the modern synthesis has run its course, and that people are realizing that a purely gene-centric approach to evolution cannot explain as much as we had hoped. The response to this has been to go the opposite extreme from the Williams/Dawkins reductionism and embrace systems theory and multi-level selection in the most extreme ways (e.g. Evolutoin in Four Dimensions and  The Plausibility of Life). This is not necessarily a bad thing; I like systems theory, and I like multi-level selection. I think this work has two major limitations, however.
  1. First, at times the organism seems to disappear as a useful unit of discussion. 
  2. Second, there is no clear idea what they are trying to explain.
The first issue would be forgivable, if proponents would more strongly own the position. Are they willing to say that Darwin was WRONG, that there is nothing unique about the organism as a unit of selection, and that it is even possible that the organism is never the significant unit of selection? They can't have it both ways; they can't trumpet mulit-level system theory, and yet claim that they are still all about the organism.

As for the second point, once we realize that they are rejecting one of the central tenets of Darwin's theory (the unique importance of organismal selection), it is unclear what they are trying to explain. Dawkins was trying to explain why specific sequences of DNA survived. He lost the organism in the process, and drifted into circularity at some point, but at least it was clear what he was trying to explain. The thing to be explained was also clear in Darwin's time. Darwin was trying to explain the design features of organisms. These were empirically study-able properties of organisms in the world, readily identified by suitable trained naturalists. Whatever aspects of the world those people were sensitive to, those aspects were the things to be explained, and they were things properly referred to be the term 'design.' If we can't use that term, how can we understand what Darwin was up to, and how can we determine if the new approaches can explain the same things, or if they are trying to explain something else? And if these new theories are not trying to explain the same things Darwin was trying to explain, and we can be sure (because he is the contrast group) that they are not trying to explain what Dawkins was trying to explain, then what are they trying to do?

At this point someone might object that the goal of evolutionary theory should be to explain 'the state of nature', or 'why animals are the way they are', or something much more general like that. I'm not sure exactly how to respond to that, except to say that such efforts seem, to me, either hopelessly ambiguous, or as not having any room for theory as typically understood. Surely we are trying to explain certain, particular, patterns that we see in living creatures, using a certain, limited set of principles. So I guess the return question would be: If we are not trying to explain the design features of organisms, then what exactly is the larger goal? What is our 'theory of evolution' trying to explain?


* The situation might even be worse than that... worse, at least from the point of view of the theorist... Worrying too much about theory might actually interfere with getting "the real work" done. This could be explained in Kuhnian terms - that during times of normal science, no one is helped by people trying to start a revolution - but the discussion in psychology goes back further. Michael Pettit and Matthew Sigal have been presenting about the origins of the APA manual at history of psych conferences, and rumor has it they have an article on the way. The most interesting parts of these presentations, for me, are the insights into how authors and editors thought of the article-writing process. There was actually a large contingent of psychologists who were against standardization, because it would hamper the authors voice, and thereby inhibit creativity. For example, they bemoaned the rise of short articles. This might seem a familiar refrain, given the recent conflicting research about whether or not short reports are a good thing.... but at the time, these critics were concerned about some overbearing editors limiting articles to 7,000 words! Fast forward to the present, and I'm in the process of condensing three studies into 4,000 words, which is considered a normal sized article in many journals. Frankly, part of the story of psychology becoming more productive as a science is a subplot about deincentivizing theory and history, and rewarding concise, straightforward experimentation.

P.S. Bjoern, has your travel schedule settled down at all yet?


  1. "Bjoern, has your travel schedule settled down at all yet? "
    Not really - am in Japan on my way to fly back to Europe. Plan to read your post on the flight (if I don't fall asleep)!

  2. "If we are not trying to explain the design features of organisms, then what exactly is the larger goal? What is our 'theory of evolution' trying to explain?"

    We use the word 'trait' which doesn't imply design. This could be one, many or all traits of the animal.

    I also don't see evolution in any sort of crisis at all. Many levels of selection simply mean that there are several factor that determine the level of selection at any given time. Sometimes it's the gene, sometimes the organism, sometimes the group, with different probabilities and frequencies all depending on various variable. I don't see how this implies any sort of crisis - transportation is not in a crisis only because sometimes we walk, sometimes we take the bike, sometimes the car, the ship or the plane.

  3. Hmmmm...
    I think I would need a while to formulate why I think 'trait' is inadequate to describe what biologists are up to. For now, all I could say is that - in general - biologists are not equally interested in all traits, and do not attempt natural-selection based explanations equally for all traits they are interested in. Thus, there is room to be more specific.

    As for 'crisis', I think I can address that pretty well:

    I was trying to invoke the Kuhnian sense of the term. We are in the process of transitioning between dominant paradigms, and no new paradigm has solidified control of the field. That's all I meant. I didn't mean to imply people running in the streets screaming, or having heart attacks at conventions, or anything like that. There is now sufficient evidence against the prior dominant paradigm, a purely gene-centric model, that many in the field are willing to consider alternatives.

    So far as I can tell, as alternatives go, the combination of multi-level selection and systems theory has the largest number of adherents... but it is still clearly a minority view. Many are still clinging to the gene-centric model, and other alternatives are being explored.

    To make things a bit more confusing: As you would expect in the midst of a Kuhnian crisis, many who would say they agree with multi-level selection and systems theory have not really thought through the consequences. Quite a few people seem to think that the ideas in The Plausibility of Life or Evolution in Four Dimensions, for example, are only a small shift from Williams and Dawkins. That is, many are agreeing with these new views in an attempt to patch up the old theory, rather than recognizing them as a new theory. But the types of science being advocated for are dramatically different.

    From my vantage point, at least, it is in no way certain how this will all play out over the next few decades.