Science Authority

Is Science an Authority? How to View Announcements from Scientists

In a previous article, I discussed why scientists (among others) are almost never interested in considering a new theory proposed by a non-scientist: because it’s so unlikely that a person who is not familiar with our best current knowledge in a given area of science would be able to come up with a useful new theory in that area of science. In this article, I’m going to turn around and look at things from the non-scientists viewpoint, and ask: how should non-scientists view public pronouncements from scientists about a particular area of science?

In that previous article, I wrote:

[P]rofessional scientists, when talking to nonscientists, often fail to distinguish the varying levels of confidence we have in different parts of science, and often present science in a way that encourages people to say “Oh, wow!” and accept whatever they are told on the authority of the scientist, rather than to think critically and try to build an understanding of their own.

This seems to suggest that the correct answer to the title question of this article must be “no”: we’re not supposed to accept what scientists say on their authority. (Indeed, we’re not supposed to accept what anyone says in their authority.) We’re supposed to think critically and try to build our own understanding.

But there are at least two objections to this. The first is that nobody has the time or the wherewithal to personally check out everything. This was true even in the early days of science, and it’s even more true today when so many experiments utilize complex and expensive technology that takes years or decades to build. You and I can’t possibly independently check the raw experimental data that comes out of the LHC or LIGO, for example. We have to trust that the people whose job it is to collect that data and make sure it’s recorded properly are doing that job. Of course, there are many checks involved in that process, but the average person isn’t the one doing them.

The second objection is that most people don’t have the expertise to second guess what a scientist says when talking about an area of science. When looking at public exchanges between scientists on, for example, whether the LIGO results are valid detections of gravitational waves, or whether string theory should have as many physicists working on it as it does, most people would be at a loss to judge the arguments being made on either side. It might even be that both sides have valid points, and there is no reasonable way for the average person to weigh the arguments.

However, it also doesn’t seem feasible for the average person to simply refrain from having opinions or making judgments on scientific questions. We rely on the products of science and technology in every area of our lives, so we have an interest in how accurate the science is that lies behind those products. Also, questions of public policy often require citizens to make judgments about scientific questions. And scientists themselves, as I said in the quote from the previous article above, often make claims when talking to non-scientists that can’t (and shouldn’t) be taken at face value.

You might be wondering, though: if we’re supposed to be so cautious about taking scientific claims at face value, how is it that answers to questions here on Physics Forums so often seem to take the opposite view? A question will come up in the relativity forum, say, and the responses will make clear that relativity, at least, seems to be considered as so well established that its claims, at least within its domain of validity, can be taken as authoritative. Or consider this hypothetical: astronomers announce publicly that they have discovered a new asteroid, not previously observed, and have computed its orbit, and it will hit the Earth sometime in, say, 2050. Would we be justified in taking drastic action as a result of this prediction, even if we as ordinary citizens can’t check it for ourselves?

There are at least two useful questions that any ordinary citizen can ask in situations like these. The first is simple: what kind of predictive track record does this area of science have? What kinds of predictions has it made that have been confirmed, and how precise were the predictions? In the case of the astronomers in the above hypothetical, there is an extensive track record of precise predictions that have been confirmed: astronomers routinely predict, for example, the distance of closest approach to Earth of asteroids, years in advance, and to a precision of tens of kilometers (i.e., much smaller than the diameter of Earth), and have those predictions confirmed. So a definite prediction that an asteroid will hit the Earth a few decades from now is highly likely to be valid.

The second question is, how are the scientists presenting their claims? I chose the above hypothetical because, of course, actual predictions by astronomers of possible future Earth impacts by asteroids have been made public in recent years. In every case, more accurate observations were made within a few months of the initial announcement that ruled out the Earth impacts. But the initial announcements themselves are instructive: the astronomers were very careful not to say they had a definite prediction of an Earth impact. They made it clear that (a) the error bars in their current data were wide, and included the possibility of a future Earth impact, but that they expected to quickly collect much more data which would allow them to make their calculations much more precise, and (b) they would not make any definite announcement one way or the other until they were sure.

In other words, the astronomers did exactly what scientists should do when they have new results that might be important to the public: they communicated what information they currently had, what the uncertainties were, and what they were doing to resolve those uncertainties. But this example might seem too easy because it was clear that it would not take too long for more accurate observations to resolve the question: the potential impact was far enough in the future that it clearly was no problem waiting a few months for a definite answer. Also, the scientists had no doubts about what they were going to do to get a definite answer.

A more interesting example is the announcement of the OPERA experimental results which, at least at face value, seemed to imply the existence of faster-than-light neutrinos. Here, the scientists basically announced that they were befuddled and were asking for help: they clearly understood that the FTL neutrino hypothesis was an extraordinary claim, but they had been unable to find any other explanation for the data on their own, so they were appealing to the world scientific community for assistance in analyzing their experiment. As it turned out, of course, there were no FTL neutrinos: the anomalous data were due to a fairly subtle issue with the experimental equipment that took quite some time to figure out.

While it was being figured out, of course, there were all kinds of speculations and discussions about possible new physics (including a long thread here on Physics Forums). But the OPERA scientists themselves were careful not to make any claims about new physics in their official statements. They took the position, as noted above, that they were simply asking for help in figuring out what was going on, and making no judgments until that process was finished. So again, I think they were doing what scientists should do in such situations.

In summary, while neither scientists nor anyone else should have their claims believed simply on their authority, there are cases where definite predictions by scientists are reliable enough to be taken as authoritative. If the scientists have a good predictive track record, and if they are presenting their information with due attention to whatever uncertainties are present, then one’s own common sense should be a good guide in evaluating their claims, and if it ends up that the uncertainties are resolved and a definite, precise claim is made in such a case, it is worth taking very seriously. If those elements are not present, however, that should be a red flag that one should not be putting too much weight on the claims being made.


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  1. PeterDonis says:
    In that sense, everyone should be a scientist, in that we hope that everyone uses sound science in forming their policy preferences.

    I see that I phrased my statement much too broadly. I should have said "claims to be communicating information that has a scientific basis which they have personal knowledge of as a researcher".

  2. atyy says:
    Of course there are many ways of answering that question. For purposes of this discussion, I would say a scientist is someone who claims to be communicating information that has a scientific basis and is relevant to some issue of public concern.

    In that sense, everyone should be a scientist, in that we hope that everyone uses sound science in forming their policy preferences.

    The preceding statement is of course, made not as a scientist, but as a lay member of society.

  3. PeterDonis says:
    What are the responsibilities of a scientist?

    I would say:

    – A scientist is responsible for honestly reporting all experiments and their results (including the raw data, not just the results of data analysis), whether or not they supported whatever hypothesis the scientist was trying to test.

    – A scientist is responsible for accurately communicating the current state of scientific knowledge in whatever field they are working in, including all uncertainties. This includes drawing careful distinctions between scientific theories that have been tested experimentally, and hypotheses or speculations that have not. It also includes carefully distinguishing their own personal opinions from scientific theories or hypotheses.

    – A scientist is responsible for not invoking the authority of Science for what they say, unless what they are saying is backed by a strong predictive track record that they can verify of their own personal knowledge.

    What are not the responsibilities of a scientist?

    I would say:

    – A scientist, in their capacity as a scientist, is not responsible for deciding what public policy should be, even in an area where their scientific work provides critical information. In their capacity as a citizen, a scientist of course has a voice in public policy, just as all citizens do, but their status as a scientist gives them no special responsibility in that regard over and above the normal responsibilities of a citizen. (They should, of course, accurately communicate the current state of scientific knowledge in discussions about public policy, but that is already covered above.)

    You might also want to say, exactly what IS a scientist?

    Of course there are many ways of answering that question. For purposes of this discussion, I would say a scientist is someone who claims to be communicating information that has a scientific basis and is relevant to some issue of public concern.

  4. benorin says:

    As I recall, statistics is the one last math course required for most non-STEM majors. But stats is not intuitive all the way through, same as probability—and on both these one must have a grasp to intelligibly interpret science claims made with uncertainties as prescribed by the OP.

    One example I’d be interested to hear the OP’s view of comes from a documentary I watched the other night: it was a homicide case and either one of the first, or the first, case depending entirely on circumstantial evidence such as fibers found on the victims were consistent with the fibers found in the accused’s house and mathematically contrived probabilities that were (iirc) many million or so to one, derived by the “and rule” of probability and based off incomplete sales records that were assumed to be complete that showed how many rooms worth of a certain carpet was distributed amongst several states and it was assumed an equal distribution amongst states for the purposes of calculating said probabilities. These “facts” were reported by the FBI using very “we-know-what-we-are-doing” posters with blown up images of fibers etc and the jury ate it up. I could go on, but…

  5. PeterDonis says:
    as practitioners of the scientific method our input should be valued on a panoply of topics

    You’re assuming that "scientist" and "practitioner of the scientific method" are coextensive. They’re not.

    I think a person’s input should be valued based on the content of the input, not on who it is coming from. Non-scientists might be just as good at constructing models and building a sound predictive track record in a particular domain as scientists are; conversely, scientists might not always do a good job of that even in their own fields.

  6. PeterDonis says:
    My intention was to make it clear that they deserve deference only when speaking of science.

    I don’t think this is quite the right way of putting it. Scientists only deserve deference when they can demonstrate the necessary predictive track record based on scientific models to support whatever claims they are making. Many scientists cannot do that even when they are speaking of science. That’s part of the nature of science.

  7. PeterDonis says:
    In order to allocate public funds we need to agree on what we will call facts.

    I agree with your general sentiment here, but I’m not sure "facts" is the best word to use in this context, because I think it promotes the mistaken view that science gives binary true/false statements. It doesn’t. Science builds models that make predictions, and compares those predictions with data. The comparison is never perfect; there are always some error bars in the predictions and some error bars in the data. Also, all models are approximations, in the sense that we can never be sure there isn’t something left out that will turn out to be significant. Using the word "facts" obscures all of these important aspects of the information that science provides.

    I think a better way of expressing the public policy aspect is to say that, in order to make a public policy decision–whether it is to allocate funds or anything else–we need to agree on what questions need to be answered to support the decision, and what our best current knowledge is regarding the answers to those questions. If our best current knowledge is "insufficient data for a meaningful answer", then the correct public policy decision is to not make a decision at all. Either that, or figure out some different public policy decision we can make that will address whatever absolutely must be addressed now, that doesn’t require having answers to questions we don’t currently have answers to.

  8. PeterDonis says:
    I cannot understand the second sentence.

    I’m asking: suppose that scientists started doing a much better job than they are currently doing, of accurately communicating to the public the current state of scientific knowledge, including all the uncertainties. Would that make the public more likely to confuse science with engineering than they are now?

  9. anorlunda says:
    But I disagree that science is just another competitor and deserves no deference.

    My intention was to make it clear that they deserve deference only when speaking of science. When a question such as "should we fund multiverse research" comes up, non-scientists should make the decision and wannabe grant recipients should be excluded. There would be no "facts" in that decision, only the prospects of success.

    Debunking superstition and misinformation is a separate topic. But one fraught with danger. In this contentious world, one man’s education is another man’s misinformation. Wannabe truthsayers beware. I think it would be wise for scientists to publish the facts as they know them, but to allow others to get up on the public debate stage.

    Sticking with the COVID-19 case, epidemiologists deserve deference when discussing epidemiology, but not when declaring what is "best" for society.

  10. atyy says:
    Re: Engineering versus science. Yes it is a continuum. My nominee for the best engineer of the 20th Century would be the physicist Enrico Fermi.

    That’s one I hadn’t heard before. But now that you mention it, it’s hard to think of anything comparable.

  11. anorlunda says:
    Thank you Peter for addressing a difficult topic.

    One important case is allocation of public funds. Citizens have the right to care how their tax money is spent, and to be skeptical of anyone coming forward with their hand out. Regarding science budgets it is fair to say that all scientists have a conflict of interest. We should reserve the spending decisions to non-scientists. But in real life, it’s often the opposite.

    Another chronic problem is scientists exploiting deference while advocating for public policies that are not science. That damages the reputation of science in general. We all have political opinions, but when someone says, "My scientific opinions count more than yours because I’m a member of this elite group. Hear and obey." that’s injurious to the group. Politicians are sometimes criticized for not obeying the dictates of scientists (not the dictates of science, but scientists speaking out on public policy issues).

    It is playing out right now with the COVID-19 crisis. We need to balance the economy versus epidemiology. Scientists should voice the scientific predictions of their models, but not dictate public policy.

    Re: Engineering versus science. Yes it is a continuum. My nominee for the best engineer of the 20th Century would be the physicist Enrico Fermi.

  12. bhobba says:
    Engineers need to be more certain that their risk estimates are correct.

    After reading Feynman’s – What Do You Care What Other People Think? (again I think something all HS students should read) you realize not only is that required, those they report to must be receptive to it. To me the difference between engineering and science is I would categorise engineering as more like applied science. Which raises the question – is applied science actually science?


  13. bhobba says:
    Excellent article about a difficult issue. When someone asks me what is the essence of science – I always say – doubt. It is of course more subtle than that, and to those that want to know more I ask them to read Feynman’s Character Of Physical Law (or watch the videos). I believe it should be part of the general reading at school for all students. With that background I think a proper socratic discussion can take place led by someone that does understand the issue – which I fear most teachers at High School do not.


  14. PeterDonis says:
    Scientists mostly investigate to understand; they theorize and test, and often retheorize to find something that fits better. Engineers must be certain.

    I’m still not sure I follow. Are you saying the public confuses engineering with science now? Or that the would if scientists did a better job of accurately describing the current state of knowledge, uncertainties and all?

  15. PeterDonis says:
    admission of uncertainty is a two-edged sword among the general public

    While this is true, I don’t think you can solve it by not admitting uncertainty. Since the public is quite capable of misinterpreting no matter what the scientist says, the best the scientist can do is to just describe the current state of knowledge, including lack of knowledge and uncertainty, as accurately as possible.

  16. PeterDonis says:
    Of course the slippery is in the final paragraph:
    "and if they are presenting their information with due attention to whatever uncertainties are present"

    It’s worth bearing in mind that in that clause, I am referring to a situation (such as the intial OPERA results) in which the scientists are explicitly not claiming the authority of science for what they say; they are explicitly saying "we haven’t fully figured this out yet, stand by for further updates in the future". And then I go on to say "if it ends up that the uncertainties are resolved and a definite, precise claim is made in such a case, it is worth taking very seriously" (emphasis added on the "if").

    definition of due attention becomes the fallback point of the contentious

    Yes, and one of the points I was trying to make is that scientists themselves have a responsibility to be very careful and scrupulous about what they say to the public in their capacity as scientists. I have seen a number of scientists bemoan the fact that the public doesn’t trust science as much as they should, but I think scientists themselves are in large part to blame, because they themselves have painted a picture of science as an authority much too broadly, instead of being careful about levels of confidence and being open about uncertainties. So when something that the public was told was "science" turns out to be wrong, the public does not get the correct message, which is that what they were told was "science" was just preliminary research and much of such research later turns out to be wrong, and that’s a normal and expected part of science. Instead the public gets the message that science is just another false authority, claiming to have an inside track to the truth when it really doesn’t, so they think they’re free to just ignore it whenever it says something they don’t like.

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