Twelve More Things Your Friends Believe But You Should Not

Following the first post called Twelve Things Your Friends Might Believe But You Should Not, here are twelve more tidbits that refute what many believe is "common knowledge."

  1. The bra was not invented by a man named Titzling. Despite the delicious tempting irony that the name of an inventor should so wonderfully match his invention, this myth originated in a satirical book by Wallace Reyburn called Bust-up: The Uplifting Tale of Otto Titzling and the Development of the Bra. The true origins of the bra are a little less certain given that breast-supporting garments have been around for centuries. The first patent identified as a brassiere was granted in 1913 by Mary Phelps Jacob, though earlier versions of the idea had been around for some time.
  2. The Great Wall of China is not the only man-made structure visible from space by the naked eyeThis claim is wrong for several reasons. "Space" is largely open to interpretation, but typically means "from orbit." Astronaut Jay Apt makes clear that the Great Wall is barely visible, if at all, from an orbiting shuttle, though other objects, such as roads and airport runways, are sometimes visible. Additionally, cities and other large composite structures can easily be seen, including the Almeria greenhouse complex and the Kennecott Copper Mine.
  3. Alcohol does not kill brain cells. Despite the prevailing wisdom that drinking alcohol can destroy neurons in the brain, scientific studies have found little to support this claim. While alcohol certainly affects brain chemistry, especially under the influence of moderate to heavy amounts, the reports of the death of brain cells has been greatly exaggerated. Alcohol can affect the dendrites at the end of neurons, though, which alters the way the neurons communicate. Alcoholics can develop Wernicke-Korsakoff syndrome which can destroy neurons, but this condition is caused by a deficiency in thiamine, not the direct effects of alcohol on the brain. Speaking of brains...
  4. You do not use only 10% of your brain. This surprisingly widespread myth has its roots (perhaps) in a wide variety of explanations and has been egged on by the recent movie Lucy, but the science behind the utilization of the brain offers no evidence that this claim holds water. Brain scans show that all areas of the brain are active at some point, some more than others, and what is being utilized depends greatly on what you are doing. Evolution tends to disfavor producing organs which are significantly beyond utilization advantages, and there is no reason to suspect that 90% of our brain just sits there, waiting to be discovered as the seat of ESP, telekinesis, or any of the many other claimed 'powers' which are said to exist in the idle neurons.
  5. There are not more humans alive today than have ever died. This idea depends a lot on how you define "human" and how long you think we've been around. Assuming that modern humans have been around at least 40,000 years, estimates put the number of dead humans in the tens of billions, perhaps in the 60 billion range, an order of magnitude more than the Earth's current population. That's a lot of seeing dead people. You'd think there would be ghosts everywhere with that many departed underfoot, which leads us to...
  6. Ghosts do not cause flashlights to turn on and off. Setting aside a moment whether or not there are ghosts, the well-known "evidence" found often on ghost tours is that such spirits can communicate by turning on and off a flashlight. This feat is explained by tour guides as a way to tell if a ghost is present and wants to talk. However, the effect of a flashlight turning on and off without human intervention is a well-understood result of the physics of specific flashlight designs. Heating and cooling elements in the flashlight can cause it to cycle for long periods of time without being touched. How about one more about ghosts...
  7. There was not a ghost in the movie Three Man and a Baby. The early-Internet grapevine went nuts around 1990 when someone discovered in one scene what was claimed to be a ghost of a young boy who had died in the house sometime before. Naturally, this "proved" that ghosts existed... until skeptics pointed out that the "spirit" in the scene had a much more reasonable explanation. What looked like a ghostly boy was instead a cardboard cutout of one of the film's stars, Ted Danson. The prop was to be part of a minor plot line in the movie but was cut out at some point. 
  8. Dropping a coin from a skyscraper cannot kill someone. The basic myth goes like this: drop a penny (or, sometimes, larger coins) from the Empire State Building and the resulting fall could strike a pedestrian and kill her. This, however, defies the laws of physics, ignoring the concept of terminal velocity. In a vacuum, it might be possible to kill someone from such a drop, but coins dropped under normal conditions accelerate only to a point which is well under that needed to create enough force to do significant damage. Certainly, it might leave a welt or a bruise, and perhaps an extreme case where someone gets hit in a particularly vulnerable soft spot it might be possible to cause serious damage, but this myth fails the tests of freshman-level Physics under all but the most unusual of circumstances.
  9. Lightning can strike the same place twiceThis misunderstanding can leave someone feeling safe when darting under the cover of a recently-struck tree, but the truth is that whatever conditions led the lightning bolt to "choose" to strike a particular place could lead to a second strike as well. This is well documented on buildings and natural objects both, and the installation of lightning rods can demonstrate this multiple-strike effect quite easily. 
  10. Vikings probably did not wear horns on their helmets. We've all seen the ferocious headgear of the Viking hoards, curving, solid horns rising menacingly from the top of helms. Even the NFL's Minnesota Vikings features the display on their emblem. No evidence exists that the Norse warriors had such decoration on their skull protection. This myth may date back to Wagner's "Der Ring des Nibelungen" in 1876 where a costume designer produced horned helmets for the Viking characters. While there is some scant evidence of other cultures wearing horns or other animal decorations on their helmets, there appears to be no proof that the Vikings were one of those groups. On the subject of other things that didn't happen in history...
  11. Columbus and his contemporaries did not believe the world was flat. Despite the romantic idea that Columbus sailed over the ocean blue to find that he lived on a sphere rather than a plane, the explorer certainly was well aware of the shape of the planet when he left. As long ago as the days of Ancient Greece there were many who had already determined the size of the sphere within a reasonable margin, and navigators had known about the spherical shape of the oceans for centuries. While it is possible that uneducated folks held flat-earth beliefs, certainly no ocean-faring ship's captain had any such misconception.
  12. Napoleon Bonaparte was not particularly short for his time. This myth is so prevalent, there's even a complex named in its honor. Even during his own time, he was called the "Little Corporal" which may have contributed to the misperception, along with enemy propaganda. The French commander likely stood between 5'5 and 5'7, a perfectly normal height for a man in France during that era. Some of the confusion came from the difference between British inches and French inches. By French standards, Napoleon's height was around 5'2 which easily confused those unaware of the longer French units.

Twelve Things Your Friends Might Believe But You Should Not

There are an uncountable number of myths, urban legends, and misconceptions that many people "know" are true. Common sense might even back them up, and if your mother said it was true, why doubt her?

Being a skeptic means going beyond acceptance of "common knowledge" and looking into the actual evidence. I've put together a list of twelve commonly-held beliefs that aren't backed up by the evidence. Make sure you pass them on to your more credulous friends.

  1. There was no War of the Worlds mass panicOrson Welles' entertaining radio tale of an alien invasion was reported by many media outlets as causing riots, suicides, and a public fearing for its safety. Instead, almost no one heard the show, and of those who did, most were not fooled into believing it was an actual situation. While there are some anecdotal accounts claiming that, in some isolated locales, police and media phone banks saw an increase in volume during the program, there is no significant evidence to believe that the media hype of mass panic was real. 
  2. US President John F. Kennedy did not claim to be a jelly doughnut in Berlin. The term Berliner was a common word for a jelly doughnut, and when Kennedy used the indefinite article ein, some claimed that his phrase stated that he was a popular breakfast item. However, Kennedy's phrase, "Ich bin ein Berliner," was exactly correct and, in the figurative sense of his statement, clearly stated what he meant.
  3. Ostriches do not stick their heads in the sand Everyone knows this imagery, often used to demonstrate the futility of trying to hide or avoid a problem. Unfortunately, this myth-which-passes-as-truth has not been observed in nature. Instead, the idea that ostriches hide their heads in holes likely comes from a sentence in Pliny the Elder's writing that stated "...they imagine, when they have thrust their head and neck into a bush, that the whole of their body is concealed." 
  4. Houseflies do not have a 24-hour lifespan. Though they certainly don't live to be what we would consider a ripe old age, the common housefly enjoys 15-30 times the longevity that this myth states. Perhaps the misconception is based on studies done in households possessing flyswatters, leading to early deaths for those so "studied." Which leads into the next myth...
  5. People did not commonly expect to die in their 30s in the last few hundred years. This myth is widespread and feeds all sorts of moral and cultural relativistic arguments. The problem is the confusion between life expectancy at birth and life expectancy after a certain age. The reduction in infant and childhood mortality has significantly changed life expectancy statistics toward older ages. However, once a person reaches, say, the age of five, or ten, life expectancy immediately rises into the 50s or 60s. Much of the improvement in life expectancy is due to reducing early deaths, not in substantially prolonging the lives of those who survive childhood.
  6. Chewing Gum does not stay in your stomach for seven years. If you've ever chewed your gum to a tough, rubbery finish, it is easy to imagine that it was too tough to break down inside your stomach. Your digestive juices have no such lack of imagination, however, and the flavorless rubber mass you just swallowed will be out of your system in just a few days.
  7. Blondes (and redheads) are not becoming extinct. Despite the common wisdom that says that these recessive genes are being passed down less and less over the generations, there is no evidence of this happening in a way leading to the disappearance of those characteristics. As with other recessive genes, the prevalence may be reduced over time with selective pressure, but to date, any claims of such an effect on blonde and red hair are likely more hoax than science.
  8. There are more than five senses. This myth is a bit more nuanced in that there isn't a consensus on what exactly constitutes a stand-alone sense. However, there are clearly several which don't fit into the Aristotolian-named and well-known five, including a sense of balance, acceleration, pain, heat and cold sensitivity. How about the sensing of the passage of time? While not all of these 'sixth senses' might be well-agreed upon, it is clear that the five senses we all know do not cover all the ways our body can receive information about the world around us. Which seques into...
  9. Your tongue can detect more than four flavors. Many people have never heard of the flavor profile known as "umami" but most everyone has experienced it when eating cooked meat or soy sauce. Umami is a term that came out of Japan to classify the experience of eating foods that contain glutamates which break down during cooking, fermenting, or ripening. The next time you take a bit of a ripe tomato, a succulent prawn, or rich seaweed, you're tasting the savory profile that is umami playing across your tongue. Speaking of tongues...
  10. Taste buds for salty, sweet, sour, bitter, and umami are not grouped on your tongueThe iconic map of the tongue has likely been shown to everyone in the US at some point, clearly demarking the four regions of taste profiles, broken up to be clearly seen as separated. The truth is that the receptors on your tongue can change shape and respond to all the flavor profiles. Some people are more sensitive to certain flavors in certain groups of receptors, but in general, the abiity to taste salt (and the other flavors) is distributed fairly evenly across your tongue.
  11. Being sucked into space will not cause you to explode. It also will not boil your blood. Despite this common misconception, frequently used in science fiction movies and books, your body is perfectly capable of staying in one piece while you quickly become unconscious and die, alone in the emptiness of space. Wait, did I say space is empty, because...
  12. Space is not empty. There are multitudes of particles of mass and energy out there in the gaps between things big enough to measure. Radiation, subatomic particles, even hydrogen atoms, and that list doesn't include the extraordinarily short-lived things called virtual particles. The next time you're travelling through the space between stars, fret not: You're not really alone.