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How to react when students doubt the validity of scientific theories

  1. Dec 19, 2011 #1
    I encourage my students to participate in class and think for themselves. I often get questions or remarks about concepts that I teach that stem either from a misunderstanding of an idea, or lack of clarity as to the evidence in support of a theory. I usually find these to be helpful in engaging the class. However, once in a while I get something to which I do not know how to react.

    This semester, I taught my university's equivalent of Astronomy 101. Toward the end, we discuss the origin and evidence for the big bang theory. I had a bit of a surprise when one of the physics majors in my class became a bit belligerent, asking questions that seemed out of place (e.g., "How can we possibly see light from the Cosmic Microwave Background if it's moving away from us?" - a question that seemed strange since we see things in our everyday lives that are moving away form us). After class, he stayed behind and proclaimed, "The big bang is stupid." I attempted to extract from him what it was about the theory that seemed stupid to him, but never got anything particularly specific. Instead, I received things like, "It just doesn't make any sense," "the universe can't have begun everywhere at once and still expand," and repetitions of, "it's stupid." He then claimed that he wanted to make it his goal as a physicist to prove the big bang theory incorrect. Interestingly, one of my humanities majors had also stayed behind, and was arguing against the physics major's claims of stupidity.

    I, however, found myself at a loss as to how to react. This person is studying to be a physicist, and I want him to be thinking for himself - however, I found his arguments to be non-arguments, seeming more like excuses for a lack of understanding than keen perceptions of problems with the theory. If the big bang is wrong, I want someone to prove it incorrect, but at the same time I don't want to see a physics major mistaking his own ignorance for holes in the theory itself - and I really don't want the rest of my class to see it that way, either. In the end, I tried to patch up the misunderstandings I could find, but got very little positive response.

    I was wondering if anyone else had come across a similar situation in any science course, and if so how you handled it. I also would welcome discussion on this type of situation in general.
  2. jcsd
  3. Dec 19, 2011 #2


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    I think some people will just never make it as physicists. One of the things you have to deal with to make it as a scientist is that you can't just call something stupid and be done with it. I don't think anything you tell him will be able to persuade him to change his mind since it's not a misunderstanding, it's an entire way of thinking that is causing this problem. I bet deep down he has his own idea of how the world should work and he just doesn't like having to think differently.

    It's a crackpot in the making :D
  4. Dec 19, 2011 #3

    Andy Resnick

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    There are at least two separate issues here- someone becoming 'belligerent' *during* class, and someone being argumentative *after* class.

    It's not clear how you reacted, but there have been (fortunately, very few) times when I had to abruptly shut down class discussion because the discourse was becoming belligerent. Once, I was discussing the reflectance and the application to listening devices based on laser illumination, which led to a discussion about search and seizure (IR cameras, millimeter-wave imaging of house interiors, etc), and when that started to stray into politics and right vs wrong, I simply called a halt and everyone complied.

    The point is, during class you have the responsibility to maintain a safe learning environment for *all* students- especially those who passively sit and listen, as they may be feeling intimidated. Do not hesitate to ask a student to stop disturbing the class.

    After class is a totally different environment: I've talked about Area 51, how the pyramids were constructed, aliens- all that silly stuff- with students because I too want to foster their independent critical thinking skills, and the best way to do that (IMO) is to engage the student directly (and honestly, with respect, etc.), and following where they lead. After class or in my office, I allow a much wider latitude of discussion than during class.

    In any case, you also have a duty to tell a student that you don't know the answer (or don't know how to answer) if that is the case. That happens to me with some regularity. When it does, you should make an honest effort to learn the answer and present it to the student.

    I've not yet had a student act like how you describe, but if that does happen to me, my strategy would start by simply asking the student "why?" "Why is the big bang stupid?" "Why do you say the universe can't have begun everywhere at once and still expand?"- pressure the student to work rationally, step-by-step, to explain their reasoning. They will most likely quickly give up and scurry off, but who knows- maybe they will get to an interesting question that you don't have an easy answer for, in which case you *both* will learn something new.
  5. Dec 20, 2011 #4
    I have actually had to do this before, but not in this particular instance . I had a christian fundamentalist in the same course last summer who occasionally brought the class to a grinding halt. He often remained after the class to argue the point. I actually found him easier to respond to, because I could identify where his misunderstandings of the science came from.

    When I was able to answer the questions the physics major mentioned above put to me, he ceased until after class.

    Thanks - this is essentially what I was trying to do. He did not scurry away (the discussion was broken up by the entrance of the next class), but I never managed to extract a meaningful set of logic from him - we went in circles instead. I am glad to hear that I wasn't completely off base, though I clearly need practice...
  6. Dec 20, 2011 #5
    I think this is a good statement to expand on - anyone in science has to struggle with their own preconceptions. As a teacher, you have to show confidence in your subject, but I think it is important to discuss how we should be skeptical of other people's theories, but also particularly skeptical of our own assumptions.
  7. Dec 21, 2011 #6
    If I ask you on a quiz how long after the big bang did the universe become transparent, I expect the answer 300,000 years. I will accept the answer "The professor says 300,000 years but I don't believe it myself". I will not accept the answer "I don't believe in the big bang". The purpose of this class is to get you to understand the theory, not to get you to believe it.
  8. Dec 21, 2011 #7

    Andy Resnick

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    This is absolutely true. In class, when we get to Newton's Laws, I spend some time discussing what a scientific 'theory' and 'law' are and are not, how they differ from 'legal' laws, and why they are different than someone's random idea.

    During the semester, we revisit this again and again- the laws of thermodynamics, "Hooke's law", relativity theory, etc. etc. I think it helps the students see science not as codified holy writ, but as it is- a dynamic living body of knowledge.
  9. Dec 21, 2011 #8


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    Your situation sounds perfect to me, an ideal teaching opportunity. there is obviously nothing holy about scientific theories, they are based on experimental data and logical reasoning. given such a situation, what about starting a project of investigating the supporting evidence and examining the critical arguments, and let people decide for themselves? becoming a physicist hopefully does not consist in being indoctrinated into accepting all the prevalent theories. I have often been frustrated in the past here on the forum by people who seem to think that everything Einstein or Feynman said or did is sacrosanct. The most obvious example is a tendency to use 100 year old mathematics (outdated and clumsy versions of tensor calculus) because that was all Einstein had available.

    I think you should celebrate this occurrence. Even if the arguments your students present are non arguments, you have learned where their heads are scientifically. I.e. they haven't a clue about scientific reasoning. Your job is to teach them how to reason, not to insist they agree with theories they obviously do not comprehend.

    Believe me I know how you feel. I was a teacher for some 50 years. It is a shock the first time you have a student ask a question that reveals just how far they are from grasping even the first thing you thought was taken for granted. Basically what you are saying is: that you had no idea teaching is this hard, that some students are as clueless as they are. But since your job is to teach them, you can only be glad they are laying their brains bare to you. Otherwise you have no hope of changing things for them.

    Of course some people are hopeless, or you simply do not have time to rectify all their difficulties. I had one calculus student that had no idea what was going on with the concept of a definite integral as an area, and I spent about three hours in the afternoon and on into the evening explaining it to her with more and more elementary examples. Finally she got it and asked a very intelligent question that showed her improvement, even beyond what was normally expected. I was so happy. But you cannot and she could not, spend three hours every day, so a week later she withdrew, and there went my success at least for that class with her.

    Teaching is like that. You spend your whole life, unless you are at a super elite, or uncaring school, helping people change their way of thinking and seeing the world. And mostly you fail. But it is the only way I know of to change people. We do not have the luxury of only teaching those who get it easily. Hang in there.
  10. Dec 22, 2011 #9
    I agree! I unfortunately feel that I fouled up that opportunity. There was a failure on my part to steer the conversation logically. I am hoping that I do better next time, and that your responses can help me to do that!

    Again agreed. I have been teaching at this college for four years now, and my goal in general has been teaching students how to reason. I find the most productive way (so far) to do so is in the laboratory setting, where the student is literally conducting his/her own investigation. I often encounter students who want to "know the right answer" as if it is available in a book, and whatever is written in the book is set in stone. What surprised me so much about this particular case, I think, is who I was talking to (a physics major). I was surprised that he couldn't give me a series of logical steps leading to his conclusion. And somehow, I also failed to lead him there.

    I am finding this thread helpful to get me thinking about how I teach. I am always trying to improve, and when I know something is missing, I want to fix it.

    It's astounding how emotionally invested you can be in teaching - you want to reach everyone. You're right about the time constraint, though - there isn't enough time to spend hours with each student who is struggling individually.
    Last edited: Dec 22, 2011
  11. Dec 30, 2011 #10
    wow, that's a beautiful story.
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