How can I tell whether my friend's scientific explanation is accurate?
Category: Society Published: December 11, 2013
By: Christopher S. Baird, author of The Top 50 Science Questions with Surprising Answers and Associate Professor of Physics at West Texas A&M University
As detailed in an earlier post, the best way to find accurate scientific information is to personally perform controlled experiments and to look up the consensus of unbiased experts as found in academic textbooks, peer reviewed academic journals, and academic/governmental websites. But what if you don't have the time, money, or understanding to use professional scientific resources to assess your friend's claims? In such cases, you can use the following informal guidelines:
1. If your friend says, "Nobody Knows!" he probably really means: "I personally don't know. Scientists likely know the answer very well, but I am too uneducated (or to vain) to realize this." It turns out that most every-day physical effects are very well understood by scientists at this point in history. Unless your friend is discussing exotic subjects such as dark matter, quantum gravity, or neutrino mass (in which case nobody really knows), the exclamation "Nobody Knows!" should be a giant red flag that any scientific explanation from this friend is going to be unreliable. For instance, a school teacher once told me that nobody knows what fire is and it will probably remain a mystery forever. A few minutes at the library revealed that traditional fire is just incandescing soot, and that my school teacher knows very little.
2. If your friend says, "It's complicated," and then gives an explanation that is vague and roundabout, he really means, "I looked up the answer once, but I personally had a hard time understanding it." Once a person deeply understands a subject, he should be able to explain its main points to a five-year-old. A person who says a subject is too hard to explain simply does not understand the subject. He may know how to apply the mathematical methods and get the right answer but fails to grasp the underlying meaning. For this reason, the phrase, "It's complicated," followed by vague wording is a red flag that your friend's explanation is unreliable.
3. Be wary if your friend says, "according to my theory" in a scientific explanation. The problem with this phrase is that your friend is demonstrating that he does not know the difference between a theory and a hypothesis. A theory is a general framework of ideas that has been confirmed by repeated, independent experiments. A hypothesis is an educated guess. Unless your friend is a published theorist with a list of experiments supporting his claims, he really means to use the word "hypothesis" but does not know the difference. The other problem with the phrase "according to my theory" is that he is describing his own individual thoughts, which is always less reliable than the consensus of many experts.
4. Your friend's scientific explanations are likely unreliable if he keeps saying the exact phrase over and over gain. Your friend is likely avoiding using different wording because he does not understand the subject and has simply memorized a two-word answer he bumped into. For example, if you ask your friend why X-rays are harmful and his reply is, "X-rays are made out of ionizing radiation that goes into your body where the ionizing radiation hurts your body because its ionizing radiation and your body does not like ionizing radiation," then that is an indication that he does not know what ionizing radiation is or why it is harmful.
5. Another red flag indicating unreliable explanations is the heavy use of buzzwords such as "frequency", "quantum", "energy field", "cosmic", "Einstein", "Galileo", or "Newton", especially if such words are used in a vague way.
6. If your friend contradicts himself within the space of a few minutes, this is a good indication that his thoughts are not logically consistent and likely unreliable.
7. Another red flag indicating unreliable explanations is if your friend uses concepts or objects from science fiction to illustrate his point. The "inertial dampers" from Star Trek are complete nonsense. A clear thinker will realize that mentioning inertial dampers in a serious discussion of real science will only cause confusion and in no way be helpful. If your friend uses examples from fiction to explain real science, he is demonstrating that he has a hard time distinguishing science fiction from science fact. Most of the exciting "science" in popular fiction is complete nonsense and has no relation to the real world.
8. You can also evaluate the reliability of your friend's scientific claims by assessing his expertise in that particular field. Experts in a certain field spend their whole life studying, learning, discussing, experimenting, teaching, getting paid for, and putting their reputation on the line for their particular field of study. That is what makes them experts and makes their explanations much more reliable than non-experts. Street smarts, clever guesswork, or watching a lot of documentaries are no substitute for real expertise when it comes to science. The key point is that they have to be experts in the particular subject at hand to be reliable. Your heart surgeon may be a genius in the medical theatre, but that does not make his off-the-wall thoughts on neutron stars any more credible. If you ask a random friend at school or work why the sky is blue, you will likely receive a nonsense answer such as "the sky reflects the ocean." Pose the same question to a friend that reads a lot of popular science books as a hobby and you might get a slightly more reliable answer such as, "light bounces off the air." Ask instead a high school science teacher and you may get an even better answer such as, "Rayleigh scattering". Finally, ask a professor of electromagnetism why the sky is blue and you will get the most reliable answer: "The sky is blue because of Rayleigh scattering plus a thermal solar spectrum plus bulk attenuation plus the non-linear human perception of color." The point is not that you should seek out a university professor for every little question you have, but that you should weight the reliability of answers you receive according to the expertise of the speakers.
In the end, the best course of action is to consult textbooks, peer-reviewed academic journals, and academic/governmental websites.