Think back to your childhood. Chances are, you learned a lot from the adults around you—parents, grandparents, teachers, and more! We tend to believe that adults know everything, especially when they tell us something is true. If the information comes from an older, wise person, it must be true, right?
However, it turns out that even the most well-meaning adults sometimes pass on information that isn’t entirely accurate. Over the years, we’ve absorbed many common beliefs and historical stories that we later discovered weren’t true at all! Exploring these widely held “facts” and uncovering the truth is truly fascinating.
1. **Dogs only see black and white**: For many years, many of us have believed that our furry friends can only see a gray world. This widely held view suggests that the vibrant colors we enjoy are imperceptible to dogs, greatly limiting their visual experience. This seems to be a well-known piece of pet trivia.
But here’s an interesting fact: it’s simply not true! While dogs cannot perceive the full color spectrum like humans can, their world is not limited to just black and white. They can actually see colors, specifically shades of yellow, blue, and gray. So while a red toy may look different to them than it does to you, they can still distinguish it from a green toy (which may appear grayish).
2. **You can see the Great Wall of China from space**: This is an impressive and seemingly obvious enduring myth. Given the sheer scale of the Great Wall, it is natural to assume that it should be visible from space. The idea that this enormous man-made structure is so vast that it can be seen from the highest vantage points on Earth has sparked the imagination of many. It is often regarded as the only man-made object visible from space.
Even from low Earth orbit, while the Great Wall can sometimes be seen, many other artificial structures are also visible from that altitude. From the moon, the only thing visible is a beautiful sphere, primarily white with some blue and yellow patches, and occasional green vegetation. Therefore, despite its immense scale, the Great Wall is not the iconic skyline landmark described in legend.
3. **You only use 10% of your brain**: This is a widely held belief, often used to suggest that we have enormous untapped potential just waiting to be unleashed. This belief posits that most of our brain is inactive or dormant, and if we could activate the remaining 90%, we would be able to demonstrate remarkable intelligence or abilities.
While it is true that not all of your brain’s synapses are active at the same time, it is incorrect to assume that the rest are simply idle and useless. In fact, your brain is constantly working, and nearly all parts of it are always active. Different regions of the brain are responsible for different functions—controlling breathing, regulating heart rate, processing sensory information, thinking, memory, and so on.
These functions continue uninterrupted to sustain life and enable you to interact with the world. Neurologist Barry Gordon from the Johns Hopkins University School of Medicine confirmed this years ago, stating: “In fact, we use nearly every part of the brain, and [most of] the brain is almost constantly active.”
4. **You swallow seven spiders a year**: This is a classic creepy rumor often used to describe how spiders somehow find their way into our mouths while we sleep. The number “seven” seems particularly specific, adding an inexplicable layer of credibility to the story. This idea may cause some people to feel a little uneasy before going to sleep.
Spiders are searching for prey, and your warm bed offers no prey whatsoever, unless you happen to have bed bugs. Spiders certainly do not intentionally crawl into human mouths, as there is no food source there and it poses a clear danger to them.
5. **Sugar will make you hyperactive**: This is a common explanation for why children become excited after attending parties or celebrations filled with sweets. Parents and caregivers have long viewed sugar as the culprit behind children’s sudden bursts of energy and difficulty calming down. It seems like common sense—give children sugar, and they’ll bounce around like springs, right?
However, our parents may have gotten this wrong. Numerous studies have specifically tested this hypothesis, and interestingly, what actually changes is parents’ perception of their children’s behavior. When parents were told their children had just consumed a large amount of sugar, they were significantly more likely to report that their children exhibited hyperactive symptoms, even if the children had actually only taken a sugar-free placebo. It seems that the expectation of hyperactivity, rather than the sugar itself, influenced parents’ perceptions.
6. **You can’t swim for an hour after eating**: This warning has been passed down from generation to generation, often accompanied by terrifying stories of cramps and even drowning caused by impaired swimming ability. The theory behind it is that eating causes a large amount of blood to flow to the stomach for digestion, which is said to cause blood to flow away from the limbs, making them feel tired in the water and prone to cramps. This claim sounds plausible enough to keep many people sitting on the edge of the pool or beach.
Fortunately, for those who enjoy swimming after meals, this is a myth that has been thoroughly debunked. The claim that blood is diverted to the stomach in such large quantities as to compromise swimming safety simply doesn’t hold water (pun intended!). While digestion does require blood flow, it does not significantly deprive muscles of blood supply during moderate-intensity activities like swimming, thereby causing immediate danger.
7. **Your tongue has different sections for different tastes**: You may have seen that diagram—the one showing a map of the tongue, with different areas labeled for perceiving sweet, sour, salty, and bitter tastes. Sweetness is at the tip of the tongue, bitterness at the back, and so on. This is often taught in schools and seems like a neat and orderly way for taste buds to work.
However, get ready for the truth about another common misconception—this tongue map is completely fictional! While we can indeed perceive different taste characteristics, they are not limited to specific areas on the tongue. All areas of the mouth containing taste buds can detect all taste characteristics.
We have debunked some persistent misconceptions about the body, pets, and daily habits. It is surprising how certain images and stories become deeply ingrained in our collective consciousness, often thanks to movies, books, or repeated storytelling, even when the reality is quite different.
