Feynman vs. Public Health (Rodu vs. Glantz)

by Carl V Phillips

I started rereading Richard Feynman’s corpus on how to think about and do science. Actually I started by listening to an audiobook of one of his collected works because I had to clear my palate, as it were, after listening to a lecture series from one of those famous self-styled “skeptic” “debunkers”. I tried to force myself to finish it, but could not. For the most part, those pop science “explainer” guys merely replace some of the errors they are criticizing with other errors, and actually repeat many of the exact same errors. The only reason they make a better case than those they choose to criticize is that the latter are so absurd (at least in the strawman versions the “skeptics” concoct) that it is hard to fail.

Feynman made every legitimate point these people make, with far more precision and depth.

Of course, you can find most of Feynman’s important insights written countless times by countless others. But the difference is that there is simply no excuse for anyone who claims to be a scientist to not have read Feynman. More important, I seldom read others’ attempts to explore “what proper science looks like” without noticing something that is badly oversimplified, over-generalized, or out-and-out wrong. The popular press versions (as well as those written for medics and public health people) are thick with those problems. Modern writers can apply these ideas to a specific topic of immediate interest, (read: don’t ignore me just because Feynman was better :-), but there is a good case to be made for finding bedrock in the classics.

When Feynman criticized pseudoscience, he tended to draw his examples from psychology and education theory; this was back when public health researchers were legitimate scientists trying to figure things out in spite of the challenges. But if you swap out a few nouns in his lectures and essays, you can create a compendium of everything that is fundamentally wrong with today’s health research — and that is particular bad in public health research.

Consider a recurring theme, the need to rule out (or at least seriously explore) alternative explanations for an observation before reaching a particular causal conclusion. This is rather obvious in the abstract, but its implications range from the patent to the very subtle. An example he gives that is somewhere in the middle of that range is a story he recounts. A psych graduate student had read that X causes Y decided to investigate whether X’, a variation on X, causes Y. He advised her to replicate the original experiment first, to make sure she could replicate the results that imply X causes Y. That way if she did find that X’ does not seem to cause Y, it would support the claim that changing X to X’ makes the difference, rather than having no idea if she did something else different that changed the result. (The story continued that she excitedly tried to take the advice, but her advisor would not let her “waste” resources repeating something that had already been done. Sound familiar?)

To take a rather more obvious case, it would be the epitome of anti-science to compare jurisdictions where fewer people smoke with those where more smoke, observe that smokers are more aggressively trying to quit in the former populations, and from that alone conclude — contrary to both common sense and what is generally accepted — that when there are fewer remaining smokers, they are less dedicated to smoking than those who have already quit. That is, instead of the population of smokers “hardening” down to those least inclined to quit, it somehow magically distills down to people who are more inclined to quit. That is obviously an extraordinary conclusion, contrary to everything we know about human behavior, so would require extraordinary evidence to support it. But even setting that aside, the described association alone is not even ordinary evidence in support of the conclusion. (You can pause here and come up with at least one alternative explanation for the observed association.)

Consider an analogous story: you observe that if the consumption of Coca Cola in a country starts to drop, you tend to see further bigger drops. You conclude that once some people choose to quit drinking it, those who are still drinking it are less interested in drinking it than those who already quit. Seriously? Did you happen to notice that your results were driven by Syria, Russia, and Venezuela? Ok, even ignoring the extremes, did it not even occur to you that whatever factors were causing the initial drop might still exist, causing further usage cessation (or quantity reduction, or serious consideration in cessation) in spite of the remaining consumers being the greater fans of Coke? Did it not strike you that even if there genuinely is positive feedback (that is, a drop in consumption itself causes an increased interest in cessation by others) there are far more plausible explanations for it than the concluding that the consumers are less interested in continuing consumption than those who already quit. Possibilities include more robust competition from expanding alternative products, changing social attitudes that create pressure to quit, or the reduction in easy access as sources of supply disappear.

Of course, that would occur to you, dear reader. Stanton Glantz is another story. The incredibly stupid analysis of smoking I describe and analogize above was published by Glantz (in a “public health” journal, obviously). His claim, and the straightforward debunking of it, are recounted by Brad Rodu here. Brad and his postdoc, Nantaporn Plurphanswat, redid the Glantz analysis using variables that were in the very same dataset Glantz used, which offered measures of differing anti-smoker punishments (taxes, etc.) across jurisdictions. Also, for those interested in deeper wonkery, they also used jurisdiction fixed effects to try to account for changing norms. You will not be surprised at all to learn that Glantz’s results disappeared when they controlled for these other factors.

The critical issue here is not that tobacco controllers lie about what data shows (we know that) or that Brad is a better scientist than Glantz (well, duh!). It is not that Glantz’s claim is wrong (that was already obvious). It is the fact that Nantaporn and Brad had to do this in the first place. Moreover, Brad was a bit hesitant about making the effort it because real science like this is hard to publish in public health.

Robert West, whose journal published the debunking, has been quoted about a million times by vaping activists for his comment on another Glantz paper, “Publication of this study represents a major failure of the peer review system in this journal.” That is certainly true for the present Glantz paper also. But it is also not really interesting because it is also true of 99% of all papers in public health that include causal conclusions (West’s journal being no exception). I am not talking about the near-ubiquitous policy recommendations (which are always garbage) or tangential conclusory statements that could not possibly be supported by the study, but specifically about the failure to properly examine alternative explanations for an observed association before settling on one particular causal story. Even a perfunctory analysis of this is relative rare, let alone the careful drilling down that a real scientist would employ.

The problem is not merely a failure of journal reviewers and editors to magically eliminate junk via (nonexistent) gatekeeping. The problem is that researchers in these fields seldom have real scientific training or experience, and so they do not even realize they are doing (and reviewing, and publishing) junk science, along with their being no career disadvantage for producing junk science. The problem is not merely with those who intentionally seek to mislead, like Glantz. The failure is far more fundamental than either lying or the notoriously sloppy behavior of the journal process. It is the almost complete dissociation of public health discourse from scientific thinking.

Feynman’s point was not that someone else should be encouraged to come along later and figure out the alternative explanation and make a case for it (though that certainly should also be facilitated, but is not in health science where critical analysis is discouraged or ignored). His point — and that of any decent fifth-grade science course — is that exploring other alternative explanations is the duty of the original researchers. If they are not doing that, they are not doing science. You do not have to drill down to the “public health” people who seek to mislead to find massive failure to do this across health sciences.

It strikes me that a good rule of thumb is that if someone writes more than one paper a year that draws nontrivial causal conclusions, then they are probably not really doing science. I am not talking about just reporting results of studies and making trivial observations about them; those papers can be cranked out as fast as field research minions can do the work. Nor am I talking about calculations or critical analyses — a good scientist could do one of those a week in this area if he really wanted to. I am talking about the brass-ring of science, offering a genuinely strong case for some specific substantial cause-effect conclusion about the world (whether the subject matter is people or particles). It takes a lot of work to explore the myriad alternative explanations for an observation sufficiently to justify a particular conclusion. If someone did not spend many months on it, he probably did not do it at all.

And yet most papers in health journals that report an observed association assert a specific a causal conclusion. Sometimes authors hedge those with weasel-words, but that does not change the fact that they made the claim. (Even worse, results where some possible association is absent often explicitly conclude the negative about causation, but that is another story.) Many authors crank out ten such papers a year. Simply put, they are not behaving like scientists. The reason that extremists like Glantz can get away with blatant abuse of scientific methods for purely political purposes is not some occasional failure of the journal process. It is because what they are doing is only slightly different from what the median author in the field is doing.


8 responses to “Feynman vs. Public Health (Rodu vs. Glantz)

  1. Feynman’s ‘Cargo Science’.

    In WW2, the US Navy arrived at a an Island in the Pacific. They were friendly to the natives and gave them gifts. They built an airstrip. At night, they lit lights along the airstrip and many cargo aircraft landed. The natives were in awe at what they saw and were overjoyed when they were given gifts by the airmen. After some months, the US Navy and Airforce moved on.
    The natives thought long and hard about what they had seen. There was only one explanation. They built bonfires along the sides of the airstrip, and, one night, they lit the bonfires….. and waited for the arrival of the cargo planes.
    ‘Cargo Science’.

    • Carl V Phillips

      Just wait, I’ll get to that.

      Also, btw, “cargo cult” is the usual term, and Feynman usually referred to it as “cargo cult science”.

    • “We have many studies in teaching, for example, in which people make observations, make lists, do statistics, and so on, but these do not thereby become established science, established knowledge. They are merely an imitative form of science analogous to the South Sea Islanders’ airfields–radio towers, etc., made out of wood. The islanders expect a great airplane to arrive. They even build wooden airplanes of the same shape as they see in the foreigners’ airfields around them, but strangely enough, their wood planes do not fly. The result of this pseudo-scientific imitation is to produce experts, which man of you are. [But] you teachers, who are really teaching children at the bottom of the heap, can maybe doubt the experts. As a matter of fact, I can also define science another way: Science is the belief in the ignorance of experts.

      -Richard Feynman, 1968, “What Is Science?”, The Physics Teacher Vol. 7(6), pp 313-320.

  2. I stand corrected.
    I’m a great fan of Feynman. I read the three volumes of ‘Lectures on Physics’ and then copied the whole lot onto my computer when the library refused to let me borrow them any more. I wouldn’t have minded had it not been for the fact that those volumes were not even on public display. They were in the cellar somewhere and you had to ask for them.

  3. natepickering

    Of course, it doesn’t help when you’ve got a scientifically illiterate “science” media whose members are more than happy to contort a (deliberately) misleading study title “E-cig Aerosol May Contain Measurable Levels of Carcinogens” into something more appropriately click-baity like “ZOMG VAPING GIVES YOU POPCORN LUNG!!!!”

    • Carl V Phillips

      It is true that a theoretical solution to the problem is that the popular press figures out they are being lied to and pushes back. But I think that is sufficiently less likely than scientific pressure forcing a reform of the field that it is probably not worth focusing on.

  4. Roberto Sussman

    Very useful insights, though I never thought I would read the names “Feynman” and “Glantz” in the same sentence (LOL).

    Today there are structural problems in the workings of science (in general) that were much milder (or non-existent) in the times of Richard Feynman. Though individual talents still make a difference, science now is mostly team work subjected to different degrees (depending on the discipline or country) of corporate criteria of “productivity” evaluation which conditions your academic survival to publish a lot (the “publish or perish” compulsion) in order to move ahead in the “rat race” to get the extra public money needed for research. The result is an exponential growth of a conceptually light literature consisting mostly of technicalities, numerical calculations and reviews. As you say, publishing really relevant “cause-effect” or conceptual research results (in one’s field) is difficult and cannot be done on a yearly “productivity” basis. One of the downsides of this corporatization of science is its active discouragement to undertake deep conceptual work that requires long range efforts. This affects even tenured scientists, not to mention young scientists without a permanent job.

    Besides these structural problems Public Health “science” on “sin substances” (tobacco, alcohol, sugar and fat) is further cursed by the triple marriage of (i) puritan healthist eugenesic ideology, (ii) the power of the special interest lobbying politics of advocacy and (ii) the money from vested corporate interests (specially pharma). The more I have been looking at PH “tobacco science” (and even epidemiological and medical literature on smoking), the more I am shocked by its misuse of statistics, distortion of results, far fetched conclusions crudely dictated by an ideological agenda. An awful combination of incompetence and dishonesty (either intended or due to conforming to herd pressure). As you say this is a deep structural flaw of the whole PH section on “sinful” substances. It is now a global problem (managed by the WHO) in which figureheads like Glantz and Chapman are not outlier exceptions but only its most visible and influential (and pathetically crackpot) expressions. However, it is more shocking to verify that most people outside PH (scientists in other fields included) are unaware of the degree of this rot.

    The notion that PH officials are “nice doctors and free activists saving lives from the perils of addiction” is now regarded as folklore (just as the notion of “science being 100% objective and incorruptible”). I think most people realize now that PH is a privileged state bureaucracy that can be quite prone to abuse and corruption. Yet, most people I’ve spoken to believe that PH only “exaggerates” or only “lies a little with good intentions” on “dangerous substances” (specially tobacco). When you claim that PH is doing much more than that: it is outright lying by means of junk science and show proof of this, most people listening think you are being too “conspiratorial”, or have no time and patience to listen to the arguments (epidemio .. what?) or doubt my qualifications: you are not a medic, so how do you know? I reply: because their studies are based on statistics and on the physics and chemistry of gases and aerosols, and I know more on these subjects than any medic you can bring to me. Yet, being a medic (specially a high ranking medical bureaucrat) still carries a lot of social weight, specially among politicians and decision makers. So, it is hard to make a point that challenges the whole “official” medical institution, but I am confident the point will be made. Future historians will regard tobacco control “science” as a late XX and early XXI century manifestation of Lisenkoism.

    • Carl V Phillips

      As usual, you make many good points and offer a lot that deserves replies. I’ll give it a go…

      I agree that it is a bit facile to neglect what has changed by saying “look, Feynman had this all figured out before I was born.” It is kind of like appealing to Bacon, which Feynman specifically condemned (indeed, literally laughed at). I am probably going to still keep doing it, though :-). On the other hand, that story of the psych student being told she could not waste time and resources actually replicating an experiment was Feynman’s own story, presumably from the 1950s, so it is not like this is all new.

      Creating awareness of the degree of rot definitely seems to be a step on the path toward doing something about the problem. Part of the problem, which I had in mind here and will continue with as I develop these ideas, is the fact that epidemiology and related social sciences are *really* hard. That is to say, they are trivially easy for aping science, but are extremely difficult for doing real science. Any six-year-old who can reach the pedals can “drive” in the sense of propelling a car forward, but they are really going to make a mess of things. Moreover, ostensibly skilled adult drivers living in Minnesota would never survive driving in Boston, let alone Bangalore. This is bad enough when everyone involved is doing the best they can. But when many people are actively trying to mislead using the “science” as props, and the vast majority of those doing it are non-malevolently inept, then it is a disaster.

      As for the last bit, I assume you are aware of Enstrom’s paper comparing these people to Lysenko. The naive belief that medics understand science is definitely a big problem. The fact that they are Dunning-Kruger about it even more so. I, of course, have noted that this — rather than the puritans and other crazies — is probably the main reason that public health sciences are such a mess. I have the advantage that if the conversation you recount ensues, I can point out that I used to educate some of the best and brightest post-graduate medics about scientific thinking, and that I really had to dumb it down to undergraduate-level as a starting point. These particular medics were perfectly capable of understanding science (unlike many), but basically had no education in it.

      And finally, you implicitly note the Big Lie problem. If someone tells a lie that is *so* big that everyone assumes they could not possibly be making it up out of whole cloth — someone would catch them at it, after all! — then it is paradoxically hard to call them on it. There are people who still believe the claimed casus belli for the Iraq War, after all. The problem is that people do catch them at it, at the moment the lie is told and after that, but people naively continue to believe it could not have been a baseless lie because if it were, someone would have caught it. Go figure.

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