BUSTING MYTHS
10 Weird Ancient Beliefs That Were Debunked By Modern Science
Published on September 1, 2024
Image: National Cancer Institute
Trying to understand why things happen is part of what makes us human. But in the process, we sometimes end up arriving at very strange—and very wrong—conclusions. Luckily, as science advances, many of these once-held truths have been debunked. From ancient myths to modern misconceptions, here are 10 bizarre beliefs that have been shattered by the power of scientific inquiry.
Life Comes From… Nowhere?
Image: Matt Seymour
For centuries, people believed that living organisms could arise spontaneously from non-living matter. This gave rise to some strange ideas—like mice and other pests being generated seasonally from river mud, fleas emerging from dust, and even fully formed geese sprouting from barnacles! However, Louis Pasteur’s experiments in the 19th century definitively debunked this erroneous notion, proving that life arises only from preexisting life.
Bleeding Is A Good Thing
Image: Hush Naidoo Jade Photography
As unbelievable as it sounds, for centuries, the pinnacle of medical science involved making an already ill patient bleed nearly a gallon of blood, for his own good (sigh). The practice, known as bloodletting, was based on the belief that it helped balance the body's four "humors" and could cure a variety of ailments. Obviously, it did far more harm than good. But to be fair, if you survived that, you could probably endure anything life threw at you.
Foul Smells Bring Disease
Image: Jon Tyson
Before the germ theory of disease, people believed that illnesses were caused by foul odors, or "miasmas," emanating from decaying matter. They weren’t entirely off course, though—foul smells can indeed signal intense microbial activity, and the poor living conditions and lack of sanitation in early modern cities were often linked to spikes in epidemics and infections. However, scientific advancements in microbiology eventually revealed that diseases are primarily caused by microorganisms, not just bad air.
Anything Can Be Transmuted Into Gold
Image: Jingming Pan
This is one of those cases where wanting something to be real badly enough can make you believe it actually is. And who wouldn’t want a formula for turning junk into solid gold? Ancient alchemists sought to transmute base metals into gold using a mysterious substance known as the "philosopher’s stone." However, after centuries of failed attempts, most of the beliefs held by the alchemists were debunked by a more scientific understanding of chemical reactions, paving the way for modern chemistry.
Eclipses Were Punishment From The Gods
Image: Jongsun Lee
Ancient civilizations often viewed solar and lunar eclipses as omens of misfortune or signs of divine punishment from their gods. From the Ancient Greeks to the Aztecs, sacrifices and rituals of appeasement were performed to ward off the worst of the gods’ wrath. However, as humanity's understanding of celestial mechanics improved—and as accurate methods for predicting eclipses were developed—these ancient superstitions gradually faded.
Fossils Belonged To Dragons And Other Monsters
Image: Jesper Aggergaard
When ancient people encountered fossils that didn’t resemble any living creatures of their time, they had to come up with explanations. But since the processes behind evolution hadn’t been discovered yet—and the age of the Earth was still widely debated—they believed the remains belonged to mythical beings such as fire-breathing dragons, centaurs, cyclopes, and other legendary monsters.
Manatees Were Thought To Be Mermaids
Image: Nsey Benajah
Tales of mermaids—half-human, half-fish beings—have captivated sailors for centuries. For a long time, rugged explorers of the seas reported encounters with these fantastical creatures, though no evidence of their existence ever surfaced. Today, it’s believed that such sightings may have been inspired by encounters with manatees or dugongs—aquatic mammals whose gentle, flowing movements could easily spark the imagination. Now, how drunk would you have to be to mistake a manatee for a beautiful mermaid? Let’s just leave it at that.
Comet Tails Were Deadly
Image: Justin Wolff
Comets have always been awe-inspiring phenomena, but in the past, they also often triggered panic and bizarre beliefs. During the 1910 approach of Halley’s Comet, the first spectroscopic analysis of its tail led to widespread hysteria when it revealed the presence of the toxic gas cyanogen. A misquotation of famed astronomer Camille Flammarion—claiming the gas "would impregnate the atmosphere and possibly snuff out all life on the planet"—was widely circulated in the press. Soon, people around the world were panic-buying gas masks and all sorts of quack products in a desperate attempt to save themselves.
Rain Follows the Plow
Image: Clark Young
In the 19th century, settlers moving westward in the United States were lured by the belief that cultivating the land would increase rainfall in arid regions—a long-debunked notion known as "rain follows the plow." The idea gained traction as farmers noticed that rainfall often coincided with their cultivation efforts. However, thorough scientific research has since disproved this myth, attributing any perceived increase in precipitation to natural climate variability rather than human activity.
Mother’s Thoughts Could Harm A Baby
Image: freestocks
The long-discredited medical theory of "maternal impression" suggested that a pregnant woman's thoughts, emotions, or experiences could influence the physical appearance or characteristics of her unborn child. This belief was widespread in various cultures throughout history and often led to practices such as avoiding certain foods or activities during pregnancy. However, with the development of modern genetic theory, this notion was firmly refuted.
