Have you heard about how Albert Einstein failed mathematics in school? Did you know that flowering sunflowers rotate so that they always face the sun? How about how we need eight glasses of water a day, or that we only use 10% of our brains?
Did you know that George Washington had wooden teeth, or that Napoleon was short? Have you heard that that the great wall of china is the only man made structure visible from space, or that goldfish only have a memory span of a few seconds.
Did you know that glass is actually a liquid, but it’s just so viscous that it seems to be solid?
Factoids like these are so common that most people have probably heard them all before. But there’s something all these “facts” have in common:
None of them are true.
“A lie can be halfway around the world before the truth gets its boots on.”
-Charles Haddon Spurgeon.
In fact, a shocking number of these commonly believed ideas, things that everybody knows, turn out to be totally false. The rotation of the earth doesn’t cause water to spiral down the drain clockwise in one hemisphere and counterclockwise in the other. Earthworms won’t regrow into two earthworms if they get cut in half. Lemmings don’t herd themselves off cliffs. Vikings never wore horns on their helmets. Many people attribute the quote above to Winston Churchill, even though it appears in print before he was even born. Somehow these wrong ideas have been so commonly repeated that they’ve become common knowledge.
We have a bad habit of accepting ideas too easily, without really considering them before we decide to believe them. Our own intuition about how we form beliefs is that when we first encounter an idea first we first try to understand its meaning, then we think about it a bit and finally decide whether to believe it or not. Research in psychology has suggested that this is not always the case.
In 1990 a team of psychology researchers performed several experiments where subjects were presented with various statements, of which some were true and some were false. Sometimes the subjects would be interrupted while they were reading the statements. The interruption increased the number of people who thought that a false statement was true, but didn’t affect the number of people who thought that a true statement was false.
It seems that if people don’t have a chance to think about a statement thoroughly, their mind will label it as true by default. Only later is false information considered and unbelieved. The conclusion is surprising, but these researchers, and later others, were able to reproduce the same effect across many different subjects and experiments. It even persisted when subjects were told explicitly whether what they were seeing was true or false. Distracting the subjects still increased how often false statements were remembered as true ones, but didn’t affect how often true statements were remembered as false ones.
“The results suggest that both true and false information are initially represented as true and that people are not easily able to alter this method of representation.”
-Daniel Gilbert, Douglas Krull and Patick Malone
This result may help to explain how false ideas spread so easily. By default we seem to passively and automatically believe most ideas we hear, but to disbelieve something is an active process. When we read something false, unless we make a concerted effort to consider it critically, the idea often gets labelled as true.
But “Who cares?“, you might say. “What harm does it do if someone wrongly thinks that WD-40 is made from fish, or that Cinco de Mayo is Mexico’s independence day?” True, these trivial factoids are unlikely to cause anyone much harm beyond, perhaps, the embarrassment of being corrected, but other widespread false ideas do cause a great deal of harm.
Take much of so-called alternative medicine for example. Belief in homeopathy, magnet therapy, crystal healing, distance healing etc. are so commonly believed in that Americans spend $34 billion every year on them. This led to the creation of the National Center for Complementary and Alternative Medicine where $20 billion has been spent on scientific research into these, and yet after twenty years this has produced no discoveries that have lead to any new areas of medical research or treatment.
As another example, common misconceptions about illegal drugs have led to nonsensical and ineffective regulatory policies that alienate and stigmatize people instead of helping them get treatment, and have also had the effect of putting disproportionate numbers of minorities in prison.
Wrong ideas can spread and become widely believed just like correct ones, and so the fact that an idea is often repeated and widely believed is actually very weak evidence of its truth. Yet, we tend to accept ideas we encounter by default, only rejecting them if we happen to consider them and decide to reject them.
The defense against belief by default is to critically appraise all the ideas that come your way. This is especially important in situations where your full attention may not be focused on the information, such as internet browsing, casual conversations, and especially advertising. We have to diligently consider each idea we encounter, lest it sneak past our epistemic defenses while we’re not paying attention.