• Islon Woolf MD

The difference between science and pseudoscience

Updated: 5 days ago


The application of critical thinking to medicine is the hallmark of my practice. Of the critical thinking skills in medicine, the most foundational and important is the ability to tell science from pseudoscience. In the next few emails, I will explain how this is done, and why having this skill is so important. It is particularly important in concierge medicine because you, my patients, are the ultimate target of medical pseudoscience. You are typically health-conscious, and self-empowered. You are first to learn new ideas, and endowed with the expendable income to act on them. You are very smart, but not “medicine” smart. Basically, a quack's dream.



The demarcation problem


Telling science from pseudoscience is critical because beliefs derived with science are far more likely to be true than beliefs derived with pseudoscience. However, as the name implies, pseudoscience looks very much like science. It can use the same language, the same buzzwords, and even quote the same studies as science. In fact, telling the two apart is so challenging it spawned one of the primary questions of philosophy, an entire sub-discipline, known as the “demarcation problem”. Philosophers like Karl Popper, Thomas Kuhn, and Paul Feyerabend spent most of their lives trying to define where science ends and pseudoscience begins.



Telling science from pseudoscience in medicine


In medicine it would appear that the task of telling science from pseudoscience has been taken care of. There are fields already pre-labeled as "medical pseudoscience", such as: Functional medicine, Chiropractic, Naturopathy, Alternative medicine, Energy medicine, Acupuncture, and Homeopathy. But, once you scratch the surface, you will find it unfair to label an entire field as "medical pseudoscience". A field often harbors a mosaic of many different beliefs. Some beliefs are science-based, and some are pseudoscience-based. Likewise, individual practitioners harbor a mosaic of different beliefs. Some practitioners will label themselves as "science-based", yet may hold many pseudoscience-based beliefs. The labels can be deceiving, especially if the practitioners themselves don't truly understand the difference between science and pseudoscience.


The real key to understanding the difference is to realize that science and pseudoscience are not fields, or practitioners, or even specific beliefs. Science and pseudoscience are methods. Methods used to establish whether a belief is true or not. A science-based belief is derived with the scientific method, a pseudoscience-based belief is derived with the pseudoscientific method.



The scientific method


The scientific method is a method for establishing the truth of a belief. It is founded on the understanding that we tend to fool ourselves. I fool myself, and you fool yourself. We tend to think our beliefs are true, when in reality, many of them are false. We are led to these wrong conclusions through mistakes our brains make; cognitive errors and biases well-documented from the field of cognitive science. For instance, confirmation bias is our tendency to seek out, recall, and prefer evidence that confirms our beliefs.


The big problem with only trying to confirm our beliefs is that confirming evidence exists for every belief imaginable. There is even evidence for Santa Claus if we look for it: there are hundreds of songs written about him, and thousands of unexplained children's gifts. Likewise, in medicine we can find evidence for every treatment. You name a treatment, and I will find you a testimonial; a patient that claims they were cured by that treatment. Unless we try to disconfirm, we can believe in anything.



Therefore, the goal of the scientific method is to account for our tendency to confirm our beliefs by trying to disconfirm our beliefs. This is accomplished by forcing our beliefs to make predictions, and then test those predictions to see if they come true. For example, if Santa is leaving gifts for children, it is reasonable for us to make the prediction that he can be seen around the Christmas tree on Christmas Eve. We can test for this by placing a camera near the tree. If our father is caught on tape bringing the gifts, we must be willing to reject our belief in Santa. The scientific method is summarized below:

  1. Belief: We have a belief.

  2. Predict: We must make predictions based on our belief.

  3. Test: We must test to see if the predictions come true.

  4. Reject: If the predictions do not come true, we must be willing to reject our belief.


Let's apply the steps of the scientific method to a belief in medicine:

  1. Belief: We believe a treatment works because it helped our friend.

  2. Predict: Our friend may have had a placebo response, or was going to get better without treatment. Therefore, if the treatment really works, it should work better than a placebo.

  3. Test: A randomized placebo controlled trial shows no difference between the treatment group and the placebo group.

  4. Reject: It appears the medicine does not work, or works in so few people, or in such a small way, that it is essentially useless.


The best way to confirm our beliefs, is to try to disconfirm them. Beliefs that fail to make accurate predictions should be rejected.


The best way to confirm our beliefs, is to try to disconfirm them.

Even when a belief is capable of making an accurate prediction, it should be further scrutinized. Science is an iterative process. Further attempts should be made at disconfirmation. Tests should be repeated, and other predictions based on the belief should be tested. Peer review by other experts, especially those in opposition to the belief, should be allowed to review data and conclusions from the tests. These checks and balances ensure no corners are cut and there is no cheating. The scientific method relies, and even thrives, on healthy opposition to beliefs from the outside.



The pseudoscientific method


Pseudoscience, like science, is also a method for establishing the truth of a belief. However, contrary to science, pseudoscience actually feeds off of our tendencies to think our beliefs are true. Instead of trying to disconfirm our beliefs, pseudoscience only tries to confirm them. It starts with the premise that our belief is true, and works backwards striving to maintain that premise. The pseudoscientific method is as follows:

  1. Our belief is true.

  2. Confirming evidence is pursued.

  3. Confirming evidence is easily accepted regardless of quality.

  4. Disconfirming evidence is ignored.

  5. Disconfirming evidence is easily rejected regardless of quality.

  6. Peer review is avoided, and outside criticism is viewed as corrupt.

  7. Our belief is confirmed.


Let's apply the step of the pseudoscientific method to a belief in medicine:

  1. Our belief is true: We believe a treatment works.

  2. Confirming evidence is pursued: The treatment helped our friend.

  3. Confirming evidence is easily accepted: Placebo effects and natural healing could explain our friend getting better, but we accept the anecdotal evidence despite its low quality.

  4. Disconfirming evidence is ignored: We are unaware of the large randomized placebo controlled trial showing the treatment does not work.

  5. Disconfirming evidence is easily rejected: Once we are made aware of the clinical trial, we reject this high quality evidence, pointing out relatively minor problems with clinical trials.

  6. Outside criticism is viewed as corrupt: Even though the scientific consensus says the treatment does not work, we don't trust the authorities, and believe Big Pharma is just trying to push other more expensive drugs.

  7. Our belief is confirmed: The treatment works.



Science disconfirms, pseudoscience only confirms


Clearly, pseudoscience is not only different than science, it is the antithesis of science. Science tries to disconfirm beliefs in a competitive process that invites outside scrutiny. Pseudoscience only tries to confirm beliefs in an insular process that avoids and vilifies outside scrutiny. Science rejects beliefs that are disconfirmed. Pseudoscience keeps all beliefs, since no attempts are made to disconfirm them. Beliefs derived with science are close to the truth. Beliefs derived with pseudoscience are unlikely to be true.


Science disconfirms, pseudoscience only confirms.

The purpose of this email was to help you understand the fundamental difference between science and pseudoscience. In my next email, I will explain the harms of pseudoscience in medicine, and why pseudoscience in medicine is on the rise. Stay tuned...