Tuesday, September 18, 2012

Demarcationitis: How easy is it to say what science is and isn't?

Well we have been having this fun little discussion over on my post about the Three Things Philosophy Can Do that Science Can't. We have been discussing exactly what the dividing line is between science and non-science (and pseudoscience, although we really haven't gotten to that in the discussion yet).

My contention is that the esteem in which many of the inhabitants of what Dostoevsky called the "Crystal Palace" hold Karl Popper's falsification criterion is grossly misdirected. But then, the inhabitants of the Crystal Palace are notable for the ease with which they can solve the most intractable problems by simply waving their hand and dismissing them as nothing but this or that, a penchant that lends credence to the criticism that the Crystal Palace is really just a gloried chicken coop.

And then, lo and behold, we find this article, published just today in the Chronicle of Higher Education, addressing just the issue we were discussing in that post, and making a point similar to the one I have been making:
For millennia, philosophers have attempted to erect a boundary between those domains of knowledge that are legitimate and those that are anything but­—from Hippocrates' essay on "the sacred disease" (epilepsy) to editorials decrying creationism. The renowned philosopher Karl Popper coined the term "demarcation problem" to describe the quest to distinguish science from pseudoscience. He also proposed a solution. As Popper argued in a 1953 lecture, "The criterion of the scientific status of a theory is its falsifiability." In other words, if a theory articulates which empirical conditions would invalidate it, then the theory is scientific; if it doesn't, it's pseudoscience. That seems clear enough. Unfortunately, it doesn't work.
Epistemologists present several challenges to Popper's argument. First, how would you know when a theory has been falsified? Suppose you are testing a particular claim using a mass spectrometer, and you get a disagreeing result. The theory might be falsified, or your mass spectrometer could be on the fritz. Scientists do not actually troll the literature with a falsifiability detector, knocking out erroneous claims right and left. Rather, they consider their instruments, other possible explanations, alternative data sets, and so on. Rendering a theory false is a lot more complicated than Popper imagined—and thus determining what is, in principle, falsifiable is fairly muddled. The second problem is that Popper fails to demarcate in the right place. 
Creationism, for example, makes a series of falsifiable claims about radioactive dating, rates of erosion, and so on, while the more "historical" sciences, like geology and astronomy, pose theories that are more explanatory narratives than up-or-down (and therefore falsifiable) protocol statements of empirical bullet points. Any criterion had better at least replicate our common-sense notion of "science," and so far no clear criterion has been able to do so. No wonder most philosophers have given up on the task. As the prominent philosopher of science Larry Laudan put it 30 years ago: "If we would stand up and be counted on the side of reason, we ought to drop terms like 'pseudoscience' and 'unscientific' from our vocabulary; they are just hollow phrases that do only emotive work for us."
I don't know that I agree with everything in the article, but it makes some interesting and valid points. It is a good read, in any case. Read the rest here.


Anonymous said...

I propose we just ask Zpenn when we want to know whether something is science or not.

ZPenn said...

Interesting article. I'm not entirely sure I understand everything the author was saying. He appears to understand that pseudoscience is incorrect, but he also props it up as a sign of the health of our society with his "every thing with substance casts a shadow" analogy. I don't think this is the case. I see pseudoscience as incredibly unhealthy. Chiropractic, homeopathy, astrology, acupuncture, and creation science are all unhealthy, and in some cases potentially dangerous.

That isn't to say that I want these things to be regulated, I'm a strong believer in the freedom to believe whatever you want to believe in. However, It is important that these things are never mistaken for science, and one's freedom to believe in these things is not the same as granting these things any status other than what they most definitely are: pseudoscience.

ZPenn said...


Are you hitting on me? =)

I appreciate the attention, but I'm in a committed relationship at the moment.

Lee said...

It doesn't appear to be that kind of hitting. ;]

Anonymous said...

Vulgarity is a poor substitute for wit, Zpenn.

ZPenn said...

I wasn't attempting to be witty, I was just responding you your facetious proposition with some meaninglessness of my own.