Remarks on the Usefulness of the Philosophy of Science

I thought it would be appropriate to open my remarks with a longish quote from Peter Achinstein, one of Jim’s teachers at Johns Hopkins University where he got his Ph.D. In his “Book on Evidence” (Oxford University Press, 2001), Achinstein writes:

“Once there was a dean at my university who was a scientist with high intelligence but low boiling point. One day at a faculty meeting, after I said something that displeased him, he replied, “Peter, you have never made a contribution of interests to scientists.” Naturally, my first thought was to take offense. But trying to maintain a generous spirit, and believing that a highly intelligent dean offers personal insults only in private, I decided what he really meant was not the singular “you” but the plural one. “You philosophers of science,” he meant, “have nothing to offer us scientists.”

This interpretation at least took some of the sting out of his remarks and enabled me to think about them more clearly. Perhaps the dean is right, I now speculated. Although philosophers of science have carefully worked out views about a range of general concepts scientists employ – such as evidence, explanation, and law, to name just a few – scientists seem to take little heed of them.” (p.3)

Achinstein is of course right on this point. While philosophers try hard to understand and analyze some of the most fundamental scientific concepts, – I would add such concepts as confirmation, theory testing, reductionism, idealization, and more, to his list – most scientists perform their tasks in either blissful ignorance of these philosophical theories or are outright hostile towards them. A particularly outspoken example of a scientist exemplifying the latter attitude is Stephen Weinberg. His book “Dreams of a Final Theory” (Pantheon Books, 1992) contains a chapter entitled “Against Philosophy”, in which he writes:

“From time to time […] I have tried to read current work on the philosophy of science. Some of it I found to be written in a jargon so impenetrable that I can only think it aimed at impressing those who confound obscurity with profundity. [… I find] no help in professional philosophy. I am not alone in this; I know of no one who has participated actively in the advance of physics in the postwar period whose research has been significantly helped by the work of philosophers.” (p.168f., his italics)

And a little earlier, Weinberg states that

“we should not expect [philosophy] to provide today’s scientists with any useful guidance about how to go about their work or about what they are likely to find.” (p.167)

It is somewhat important to notice that Weinberg talks about today’s scientists when he says that they won’t find any help in the philosophy of science. For as he himself is well aware, and discusses in the very same chapter, the philosophical movement called ‘logical positivism’ was integral to the development of physics between Mach and Einstein. Positivism was one of the first (and maybe the last) somewhat homogeneous movements in the philosophy of science. It emphasized, among other things, the requirement that our theories be grounded in what is observable and, in its bolder moments, declared any statement that cannot possibly be tested by experimentation to be cognitively meaningless. While Weinberg acknowledges the positive influence of that doctrine on the development of, especially, the Special and the General Theory of Relativity, he complains that it did harm to later developments in elementary particle physics post WWII. Specifically, the newly formed quantum field theory, and the introduction of quarks, charms, and many other things, faced sometimes fierce resistance because of the prevailing positivist mindset.

It is important to note, however, that this positivist mindset was not the philosophers’ mindset. By the 1940’s, positivism had been abandoned by the philosophers for largely philosophical reasons. But if Weinberg is right in his account of the problems faced by particle physics, the news hadn’t reached the physics community. Whose fault that is remains to be discovered, although it should be clear that Weinberg overreaches when he lays the blame squarely on the shoulders of the philosophical community.

Still, the question remains: Is there anything useful in philosophy of science for science? Well, it depends on what you think would make philosophy of science useful. Here are two possibilities.

One might think that philosophy can help scientific progress by making the scientists better at what they do. If usefulness is understood that way, philosophy of science is probably not going to be useful. Developing theories, testing them in ingeniously set-up experiments, developing mathematical tools as needed, are parts of science that philosophers largely are, and ought to be, silent about (one interesting exception is Paul Teller’s work on the justifiability of infinite renormalization in quantum theory). Just as baseball players can be good at their game without advise from physicists, so scientists can be good at their “game” without the advise from philosophers. (Neither of which implies, of course, that the physics of baseball is an illegitimate subject matter for physicists, or that how science works is an illegitimate subject matter for the philosophy of science)

A more promising possibility is that philosophy can be called upon to inform some of the more fundamental debates in scientific methodology and/or epistemology. Ironically, Weinberg, who so clearly despises philosophy, gets himself involved in just such a debate. Some background. The book I was quoting from was in part a plea for getting funding for the Superconducting Super Collider in Texas. A central piece of Weinberg’s strategy was to argue for the importance of particle physics, more precisely, for the fundamental importance of particle physics. He attempts to do this by arguing for a thesis called reductionism, which, briefly, is the view both that everything in the universe is constituted by some fundamental entities and that every high-level regularity, or law of the special sciences, such as chemistry, biology, etc., is ultimately a special manifestation of the fundamental laws governing the behavior of the fundamental constituents of everything. The point of the strategy is obvious: We need the Supercollider, because it will allow us to discover those fundamental laws on the basis of which we will understand everything else.

What’s not so obvious is how Weinberg’s argument for the thesis of reductionism is supposed to go. The best I could find, in the middle of a discussion of the politics behind the debate, is this:

“The reason we [the particle physicists] give the impression that we think that elementary particle physics is more fundamental than other branches of physics is because it is. (p.55, my emphasis)

(In all fairness it has to be acknowledged that he says more about this, but in the final analysis, it all really amounts to the statement just quoted.)

That’s sad, if it’s supposed to pass as an argument. It’s even sadder, when one considers the huge amount of philosophical literature on this topic. This literature has its roots in the writings of the logical positivists, but it has become increasingly sophisticated over the last half-century or so. To figure out which version of reductionism is the most promising, and how it is best understood, are by no means easy tasks. In fact, the debate is still going on, and philosophers look at the best developments in the empirical sciences for evidence for one or another theory of reductionism. One might be even so bold as to imagine a world in which the Weinbergs, who want to defend the fundamental importance of their discipline, look at the best available philosophical theories concerning reductionism.

The obvious answer, then, to the dean’s challenge to Achinstein should be this: Well, there is stuff out there in the philosophy of science, useful for some aspects for doing science. (And it’s not just about reductionism; it’s literature concerning idealization, approximation, causation, model selection, etc., to name just a few). What we need is a framework in which philosophers and scientists can fruitfully cooperate without one seeing the other as invading their turf or being patronizing. Of course, I have no clue as to how we should institutionalize such a framework, but I think we should have a debate about it. Thanks.