The most recent few posts on Faculty of Language delve into some interesting questions in philosophy of science. The focus of these posts is falsifiability as a criterion for theory (or ‘proposal’, which is a kind of not-quite-theory theory) evaluation. They’re worth reading in their entirety, I think, but I wanted to briefly discuss a couple issues that deserve some elaboration.
In the first post in the series, Norbert writes (emphasis mine):
Lakatos talked about central belts versus auxilliary hypotheses…, but now pretty much any account of how the rubber of theory hits the road of experiment highlights the subtle complexities that allow them to make contact. This said, scientists can and do find evidence against particular models (specific combos of theory, auxiliary hypotheses, and experimental set-ups), but how this bears on the higher level theory is a tricky affair precisely because it is never the theory of interest alone that confronts the empirical jury. In other words, when something goes wrong (i.e. when an experiment delivers up evidence that is contrary to the deductions of the model) it is almost always possible to save the day by tinkering with the auxiliary hypotheses (or the details of the experimental set-up or the right description of the “facts”) and leave the basic theory intact.
He follows this up with a discussion of physicists figuring out the appropriate energy range to look for evidence of the Higgs boson. I won’t claim to know much at all about the standard model in physics, but I don’t think that physicists probing multiple energy ranges in the search for the Higgs boson is a good example of saving a theory by tinkering with auxiliary hypotheses. A better example would be, say, if physicists didn’t find any plausible Higgs-related signatures in their particle collision data, so they revised their (auxiliary to the standard model) hypotheses about how the particle detectors function.
But there is a larger point to make, namely that even if you have a picture perfect illustration of theory-saving auxiliary-tinkering, this is a far cry from the claim that “it’s almost always possible” to empirically insulate a theory this way. A single instance does not a general fact make.
Furthermore, even if you could, in general, change auxiliary hypotheses to save a theory, it doesn’t follow that you should do so. Larry Laudan discusses this in detail in his essay Demystifying Underdetermination, which is highly recommended.
The other issue I wanted to touch on is Norbert’s conflation of personal taste and more objective criteria of theory evaluation in his cowbell proposal (follow-up here). The basic idea here is that theories that are interesting are good, theories that are boring are not, and whether a theory is interesting or boring is unrelated to that theory’s truth or falsity.
Having read lots of Larry Laudan’s work on philosophy and history of science, I’m convinced that theories are (appropriately) evaluated on multiple dimensions. Norbert touches on some (more or less) objective criteria (e.g., whether or not a theory makes surprising predictions), but his notions of interesting/boring and “explanatory oomph” seem to be very subjective and share some of the problems that his notion of elegance (also) exhibits.
Specifically, to the extent that we can get useful definitions of ‘interestingness,’ ‘boringness,’ or ‘explanatory oomph,’ my guess is that they will be functions of more objective (and readily, rigorously defined) theory evaluation criteria that have real epistemic value. Norbert seems to be getting, at least in part, at the fecundity of a theory, with maybe a dash of explanatory scope thrown in for good measure, but when he writes things like “de gustibus very much disputandum est,” he is clearly, deliberately invoking subjective criteria.
This seems to me to be a lousy theory of theory choice. It’s not even really a theory, more just a post hoc description. Saying that GB theory became less interesting, more boring, and lost explanatory oomph seems, at best, to be saying something about syntacticians’ personal opinions of the theory. Such opinions may well be based on epistemically valuable criteria, but the interestingness/boringness is produced by these criteria, and it’s these criteria that function scientifically to enable theory evaluation, not the interestingness/boringness per se.
For example, people may be finding GB more boring because it has reduced fecundity, or maybe because there are inconsistencies between it and other, neighboring cognitive theories. (I get a sense of the latter when, e.g., Norbert writes that, in the minimalist program the faculty of language “is a congery of domain general powers (aka operations and principles) with a small dollop of linguistic specificity thrown in.” GB was nothing if not highly linguistically specific.) But if you’re going to convince anyone that GB should be abandoned for the prettier, younger Minimalism, you won’t get very far just by arguing that the former is boring and the latter interesting.
All that said, there’s much I agree with in the FoL posts (naive falsificationism is bad, m’kay?), and whether you agree with Norber or not, they’re thought provoking and good fun to read.