Scientific method and demarcation

In The Scientific Method, Mike Zajko sets out an argument that “no agreed-upon formulation of the scientific method exists” and that “it is more effective to consider science’s methods in terms of Hugh Gauch’s ‘general principles of scientific methodology'”, going on to consider whether climate science adheres to these principles. Zajko is particularly interested in the demarcation problem. In this entry I look at his comments and critique or expand on them as appropriate.

It is probably fair to say that the claim that that there is no single scientific method is now standard in the philosophy of science. Sociologists and philosophers of science determined this straightforwardly enough by looking at, for example, whether geologists follow the same approach as biologists, or comparing condensed matter physics with particle physics and organismic biology with molecular biology. Historians of science and other philosophers (those who followed the so-called historical turn, like Kuhn and Feyerabend) examined various attempts at scientific method and considered what would have happened to famous examples of good science if the method had been followed, showing that methodological strictures would have stopped science in its tracks. (This was the source of Feyerabend’s “anything goesreductio, which Zajko – like most commentators – does not recognise as a reductio, in spite of Feyerabend making it very clear.) The result was a realisation that the demarcation problem is probably insoluble (hence Laudan’s paper The demise of the demarcation problem) and that insistence on a unique scientific method is a rhetorical move rather than a rational one. I return to this point below.

In discussing John Gauch Jr.’s scientific principles as a potential alternative, Zajko describes parsimony as “an essential and pervasive principle of scientific methodology” due to the underdetermination of theories by the available data. Although it is easy to see why parsimony has methodological appeal (after all, why would we add or invoke unnecessary entities in our explanations?), the problem is that “the consequences of additional entities or assumptions are impossible to state a priori“: it takes time to understand these and, by the time we have done so, parsimony plays no role in our decision to choose one theory over another. I provided several examples of this in my essay on Ockham’s razor.

Zajko observes that scientists “are often unaware of the presuppositions on which their work is based” and points to Gauch’s discussion of some of them, although Gauch does not mention Holton’s investigations of the thema involved in science, which is an area that could perhaps profitably be explored with regard to climate science. It is interesting that Gauch does not mention abduction when considering the role of logic in science but Zajko’s suggestion that it “might be a good idea to devote some time … to statistical methods” is a good one, particularly if it includes the sociological question of whether (or to what extent) scientists are actually using the approaches recommended to them by philosophical, statistical or otherwise.

Zajko notes that Popper’s falsificationism was subject to severe critique but then goes on to claim that “falsification as part of hypothesis testing remains a powerful principle in scientific practice”, which makes little sense. The arguments against falsificationism, which I reviewed here, preclude our interpreting it as a form of hypothesis testing because linking experimental results to refution of a theory was precisely where falsificationism failed: an apparent falsification may be of an auxiliary hypothesis, as Zajko points out when referring to Lakatos’s criticisms of Popper, but he misses Lakatos’s logical objection that, since no proposition can ever be proven by experiment, neither can it be disproven.

The general problem with discussions of scientific method is exemplified by Feyerabend’s critique of Lakatos’s “solution”, his methodology of scientific research programmes. Lakatos argued for a classification of research programmes as progressive if they demonstrate excess empirical content that has been confirmed (and degenerating for the converse) and admitted that a new theory could initially display a loss in empirical content as it becomes established, adopting ad hoc measures in order to avoid falsification if necessary. The difficulty identified by Feyerabend was that Lakatos had described a methodology but – in order to avoid the problems with demarcation – not how we should act. This is where Feyerabend’s reductio could be employed again: how would the actions of a scientist following Lakatos’s methodology differ from those of a hypothetical “epistemological anarchist”? At the time of Galileo, for example, a person could reject Copernicanism as a degenerating programme and accept Aristotelianism as progressive, or vice versa, with good reasons in both cases. Even a continued failure to demonstrate increasing empirical content can be excused on the grounds that more time is exactly what a research programme always needs (as in the examples in the linked essays).

Zajko considers climate science in the light of his discussion and claims that it also suffers from a disunity of methods. Looking at it in terms of the criticisms of falsificationism suggests, as he notes, that we should not expect decisive confirmation or refutation because it is comprised of a constellation of methods, theories, models and lines of evidence. Indeed, in a previous post, I argued that disunity and a diversity of approaches play (or perhaps could play) an important role in science, and that if we move away from seeking definitive answers then what are ostensibly difficulties, such as the demarcation problem, become strengths because they point to science as a endlessly creative process rather than a fixed method. However, the real difficulty is reconciling a more nuanced philosophy of science with politics and the (understandable) demands for immediate action, a balancing of the inevitable incompleteness and uncertainty of science with the reality that our decisions are thereby also fallible but still have to be taken.

To close, and given this situation with regard to scientific method, what I want to consider now is why so many people insist – usually in public discourse – that there is such a unified and well defined method, often not hesitating to pour scorn on those who fail to follow its supposed dictates.

The answer – an obvious one, hopefully – is that the existence of the so-called scientific method is a useful rhetorical tactic to employ, especially when hoping to accord a theory scientific status or deny this to another. Where a uniform methodology exists, particularly one defined by a short list of clear steps, it is a relatively simple matter to compare the approach of some “pseudoscientist” or other with the “scientific method” and note that one or more key stages is missing – the failure to make a claim falsifiable, say, or even to attempt refutation where falsification does seem possible. This then allows the critic to dismiss the claim as pseudoscientific or non-scientific, with consequences such as a decline in funding if the objection convinces those who allot resources. Notice also that a self-fulfilling prophecy can occur: if an idea is characterised as pseudoscientific and support is withdrawn from its development then it should be no surprise when it founders and the charge of pseudoscience appears justified post hoc, confirming the earlier complaint.

The appeal of a unique scientific method is thus a powerful one, and even moreso to a person wanting to cleave the world clearly into scientific and non-scientific parts. It grants considerable power to the status quo and to academia, or more specifically those who take it upon themselves to advocate the method and use it to demarcate between theories to the cost of those not making the grade. If applied consistently, of course, it would commit us to calling much of what goes on in science today (along with almost all of what passed before) as pseudo- or non-science. This is an example of selective skepticism, in that the same “critics” who are constantly on guard against cranks and crackpots do not also take their “scientific method” and regularly test to see whether practicising scientists are adhering to it – and, from their perspective, it is as well they do not. Whether an understanding of why people resort to the rhetoric of scientific method can be separated from the political pressures and contexts in which science operates is another thing.

In any case, why should a methodology describing a fallibilistic endeavour (which everyone accepts science is) not be fallible itself? Why should theories forever be susceptible to refutation but not the (supposed) approach that led us to them? It is difficult to see why a methodology that was arrived at in a historically contingent fashion to govern a fallible enterprise should itself be considered settled once and for all, as well as not subject to its own requirement for skepticism. The important point, however, is that this inconsistency shows us that the appeal to the scientific method is indeed a rhetorical strategy: if a step-by-step method is important enough to insist on then its application must cover all of science.

It may be that this is another legacy of positivism and there can be little doubt that some people really do believe that science can be defined by a procedural list. Nevertheless, the tragedy is that those so enamoured of science that they become scientistic and elevate their simplisitic approach to the status of a canon are the very ones who then deprive themselves of an appreciation of just how rich science is on its own terms, without the attempt to force it into a methodological straightjacket. Judging by its history, science has worked so well because the scientists of the past refused to be bound by what was expected of them and struck out on their own. Sometimes this can lead nowhere (although even this is not clear), but it can also result in the re-enchantment of the world that those who love science know only too well.

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2 Responses to Scientific method and demarcation

  1. Michael S. Pearl says:

    Whether wittingly or unwittingly, Judith Curry succinctly revealed a very real problem – in fact, the core problem – with science when she said :

    Scientists learn some sort of scientific method by osmosis from the culture of the field; rarely is this reflected on by most scientists.

    The fact that science has become essentially a culture is not, in itself, the problem. After all, it is to be expected that any prolonged public exchange of explanations, insights, beliefs, and the like will develop into a culture. The problem with science is nothing other than the problem which threatens all cultural entities, and that problem (which tends toward malignancy in all cultures) occurs when those immersed in the culture do not adequately consider how the perspectives which define the background context (or culture) determine what ideas (including ostensibly new ideas or discoveries) will be deemed respectable or acceptable, if not correct or true.

    Conventional scientists, which is to say those whom Judith Curry describes as rarely reflecting on “the culture of the field”, might think that science effectively (or sufficiently) reflects upon itself by perpetually testing all beliefs and conclusions so that it thereby renders unnecessary any other sort of reflection.

    Such a way of thinking would certainly go a long way towards explaining why so many scientists seem to regards philosophy and history as irrelevant to science, but such a way of thinking would also actually confirm that many scientists are genuinely devoid of reflection about their own thinking — including, for instance, to what extent their thinking displays logical validity.

    For the sake of science, maybe the distinctions most worthy of pursuit are not those between science and pseudo-science but, rather, between scientists and technicians — between those who think and those who test.

  2. Toby Simmons says:

    Very nicely put! I enjoyed reading it.
    Great blog, by the way. Let me know what you think of mine . . .
    Keep on posting!

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