There is an episode of Dragons: Riders of Berk in which the town is plagued by lighting. The frequency of lightning strikes has suddenly increased, from being rare to being almost constant. The Berkians are Vikings; they attribute their problem to the wrath of Thor, and the story follows their blundering attempts to appease him. Eventually they realize that the iron dragon perches they had installed around town at the beginning of the episode are what is attracting the lightning. They remove these perches, and the lightning stops.
From this experience, the Berkians learn a valuable lesson: Thor disapproves of tall metal objects.
This is good comedy, but I saw a serious side to it as well. As the credits rolled, I said to my children: “As long as they believe that it’s Thor causing the lightning, they will never learn how electricity works.”
There is, I think, nothing more effective at discouraging people from learning about something than the belief that they already understand it. When we are aware of our ignorance, our curiosity is aroused. Curiosity leads to inquiry, and inquiry leads to knowledge. Even if awareness does not lead to knowledge, it can at least save us from false confidence.
The Vikings of Berk made a significant discovery: Metal attracts lightning. This discovery could easily have been the starting place for inquiry into the nature of lightning, which could have lead to knowledge of electricity, which could have lead to things like cool dragon headlamps. But that inquiry will never take place because the Vikings believe that they already understand the nature of lightning. Their belief that they know will keep them in ignorance.
The Berkians’ belief in Thor is benign enough that it can be laughed at, but false knowledge in the real world often has catastrophic consequences. Human beings are renowned for our intelligence (some claim we’re even smarter than porpoises), and we can figure out a solution to any problem that confronts us… But we often don’t. In fact, we often suffer loss, pain, and death due to problems whose solutions are really quite straightforward. When this happens, false knowledge is usually a contributor.
One bit of false knowledge that has contributed to the needless suffering and death of millions if not billions of people is the theory of the four humors. It is a simple idea that originated in antiquity: Essentially, the body is composed of four elements. People are healthy when the elements are in balance, and unhealthy when they are not. This theory was accepted by Western academics for millennia, and was the basis for much of Western medicine right up into the age of steam. The theory has both logic and poetic charm. It is also 100% wrong.
The theory of the four humors was fairly harmless in itself. It is the reason why doctors used to bleed people (too much blood throwing the humors out of balance), but very few people died from over-bleeding. The real harm of the theory was that, for generation upon generation, doctors thought that they understood the nature of disease when they did not. People were not aware of their ignorance, and so they were not curious. Without curiosity, they did not inquire. Without inquiry, solutions to disease as simple as hand-washing went undiscovered. Thus the theory of the four humors worsened virtually every instance of disease in Western history.
False knowledge is something that is much easier recognize in others than in oneself. This is not always because of vanity or chauvinism: when you have believed something for a long time, it feels right to you. It becomes part of the context in which all of your thoughts occur; other ideas wrap around it, shaping the whole. To you (who presumably do not believe in Thor), the idea that Thor causes lightning seems obviously foolish. You can probably provide a rational explanation as to why it is foolish, but why does it feel foolish? Before you dredge facts about atoms and electrical resistance from you memory, before you have any cogent thoughts at all, it instinctively feels wrong. Likely, it is this truth instinct which prompts your reason and memory to begin working out the reasons why. You are fortunate, in this case, that your instinct is correct, but that is merely good fortune. If you had been born a Viking, then it is belief in Thor that would have felt right, and your instinct would have suppressed your reason, not called it to action.
It is never safe to assume that an idea is right because it feels right. Ideas don’t feel right because they are right. They feel right because we are used to them, and people can get used to anything.
Fortunately, we are not helpless before our instincts. We do not have to wait for an idea to feel wrong before we question it. In fact, ideas that feel right are the most important ones to question, because it only by questioning them that we can test if our truth instinct is trustworthy. If we do not test our instinct, then we may be satisfied with Thor and never discover electricity. We may be satisfied with the four humors and never learn to wash our hands.