Deconstructive empiricism

Wed 26 May 2010 12:23 PM

I've been thinking about Bas van Fraassen's epistemology. Here are some distinct points: a clarification, an objection, and a question

The clarification

The usual story goes like this: Anti-realism as a semantic doctrine was seen to be a dead letter, but van Fraassen's The Scientific Image resuscitated it as an epistemic doctrine. In the decades since, a thriving literature in scientific realism has developed. Realists disagree among themselves about exactly why, but they generally agree that we ought to believe our best scientific theories - including its unobservable posits.

This becoming the crux of the issue is ironic, because this form of 'scientific realism' is not opposed to van Fraasen's anti-realist constructive empiricism.

First, because van Fraassen thinks that this way of posing the problem is confused. He thinks that rationality never obligates us to believe anything. Rather, it gives us permission. Given such an account of rationality, its simply misleading to ask whether we ought to believe any specific thing. Moreover, he admits that it is permissible to believe in the unobservable posits of our best theories.

Second, because van Fraassen doesn't see the disagreement as one about epistemic attitudes at all. Instead, it's about the proper aim of science. He puts the point this way:

Scientific realism and constructive empiricism are. as I understand them, not epistemologies but views of what science is. Both views characterize science as an activity with an aim - a point, a criterion of success - and construe (unqualified) acceptance of science as involving the belief that science meets that criterion. According to scientific realism the aim is truth (literally true theories about what things are like). Constructive empiricism sees the aim as not truth but empirical adequacy.*
And that's the catch.

The objection

I don't think science as an activity has a singular point. I haven't argued this at length, but I intimate it in my dcog paper.

Of course specific scientific projects can have identifiable purposes. A particular drug trial may be to determine whether the drug is safe and efficacious, for example.

And of course specific scientists may be involved in science for identifiable reasons. This may be to discover truths, to make true predictions, to make the world a better place, or just to impress their parents.

Scientific realism and constructive empiricism both need more. They need there to be a purpose to science altogether - SCIENCE write large. Even supposing that there is such a purpose, it is not something that can be divined by a priori rumination. As van Fraassen admits, our account of what science is about must accommodate the actual history of science. It is a partly empirical enquiry responsible to evidence.

In this enquiry, what are the phenomena? Conservatively, we might answer that the phenomena are historical documents and physical evidence. More liberally, we might say that phenomena are the actual historical activities of scientists.** Yet under no account is the aim or purpose of the activity itself among the data. The aim of the activity is a posit, introduced as part of a philosophical-historical theory. Moreover, it is an unobservable posit.

Therefore, an agnostic (who declines to believe in the unobservable posits of even the most successful theories) must decline to believe in the aim of science. This follows regardless of what the aim of science is posited to be, so an agnostic must decline to be a constructive empiricist.

This would be a problem for van Fraassen, who thinks that agnosticism is a natural position for constructive empiricists. I see two possible replies.

First, he might stick to his agnostic guns. Refusing to believe in constructive empiricism, he still might accept it. That is, he could treat constructive empiricism as involving not a true theory about science but instead an empirically adequate one. This involves some mental gymnastics, but being an agnostic already involves mental gymnastics. This meta move is only a small additional flourish.

Second, he might deny that the aim of science is a theoretical posit. Perhaps history is not a science. Perhaps discovering what what science is is not history. I don't see this line as terribly promising.***

The question

Van Fraassen has argued that we need a richer epistemology, one which allows for more than just binary beliefs or probabilistic degrees of belief. Moreover, he resists formal models of belief as direct representations of entities in the mind or brain. Yet he does seem to genuinely believe in states of opinion, "real epistemic attitudes, pointed to by traditional epistemology, which cannot be accommodated in the probabilist models we have developed so far."*

As Sellars and Churchland convincingly argue, though, epistemic attitudes like this are not among the immediate phenomena of the world. We posit them as part of a (folk) psychological theory. An agnostic about scientific and folk scientific theories ought not to believe in beliefs.

Does van Fraassen acknowledge this anywhere? or is his psychological musing a personal matter rather than an announcement ex cathedra qua constructive empiricist?

* Analysis 58.3, July 1998

** Even van Fraassen would allow the more liberal construal, since he thinks that past objects count among the observables.

*** Admittedly, I see science as basically synonymous with responsible enquiry. For someone with a narrower conception of science, perhaps this line of response could go further.

Note: I cross-posted at It is only a theory, and there are lively replies there as well.


from: Matt Brown

Wed 26 May 2010 01:55 PM

On the aim of science: could it be "solving problems"? Is that too trivial?

from: P.D.

Thu 27 May 2010 07:40 AM

Matt: If we understand problem solving in a broad, pragmatist way, then it's the aim of science. But which problems? And solved how? The bare idea of problem solving is not specific enough to distinguish realism from constructive empiricism, nor is it specific enough to structure analysis of science as d-cog.

from: Matt Brown

Thu 27 May 2010 11:38 AM

Well, maybe it's a start. After all, if the aim of science is problem-solving, that's not empty; it means that the aim is not guarantee eternal salvation, or disseminate accepted beliefs, or entertain TV viewers (though, given the bare definition, perhaps problems could arise in each of those pursuits that might require scientific attention). Now, the pragmatists add enough meat on the bones of problem solving to distinguish it from attempting or pretending to solve pseudo-problems or ignoring problems in hopes they'll go away (or the claim to do so), so that's a little further.

Dewey adds that science is distinguished from more pedestrian problem-solving (common sense inquiry) in that the problems are set not by immediate difficulties in everyday affairs (problems of use and enjoyment), but rather by the use, development, and testing of conceptual materials (theories, conceptual schema, paradigms, research traditions, or whatever). There will be intermediate cases, of course, but clear poles as well.

This gives us a singular aim of science that is pretty substantive, which seems like more than you wanted to allow.

Could it settle the issue between realism and constructive empiricism? I could see it doing so somewhat indirectly, via arguments about what this particular kind of problem-solving requires: I think Dewey thought ontological commitment went not with observability, but according to the functional role of the thing in the inquiry, not unlike a kind of abstract and broader version of Hacking's experimental realism; I could see one arguing for stricter realist or empiricist readings of the requirements of problem-solving, though.

Could it structure an analysis of science as d-cog? I suspect so, but on my looser interpretation of what that requires. On this point, though, I have no real interest in becoming the kind of empirical researcher it would require to make the point.