10 Things People Thought Lived Inside Their Bodies

iStock.com/Paul Campbell
iStock.com/Paul Campbell

The human body is full of weird, gross and awe-inspiring stuff as we know it—but for people who lived when ideas were unbound by strict anatomical correctness, it was even more so. Here are 10 things people thought, and in some cases still think, were inhabiting their bodies.

1. THREE SOULS

The existence of a physical soul inside the body was widely accepted by Greek philosophers and physicians. Plato had posited in the Timaeus that there were three souls: the Immortal Soul in the head, and a Mortal Soul divided into two parts by the diaphragm. The upper Mortal Soul was the Irascible Soul which assisted reason against desire. Beneath the diaphragm was the Appetitive Soul, which just plain desired. The diaphragm was an essential barrier keeping this hungry proto-id from being a bad influence on the Immortal Soul.

Claudius Galenus (130-199 CE), doctor to the gladiators of Pergamon, had a great deal of practical experience in the treatment of injury. However, he only ever dissected animals (mainly monkeys), so as far as he knew, there was all kinds of space inside the human body for souls to inhabit. Following in Plato's footsteps, Galen defined the three anatomical souls thus: Rational, seated in the head; Spirited, seated in the heart; and Desiderative, seated in the liver. These spirits were composed of matter, corporeal even if ethereal.

2. PNEUMA

Hippocrates (460-370 BCE), the father of Western medicine and he of oath fame, and his successors, most notably Praxagoras (born ca. 340 BCE), believed that the arteries carried a vital force called pneuma, a sort of heated air that was the source of both life and spirit.

Cadaver dissection was taboo, so most of the ancient Greek doctors got their ideas about the soft tissues of bodies from observation of the living or the vivisection and dissection of animals. Because the arteries of dead animals are virtually empty, Praxagoras concluded that arteries and veins were separate circulatory systems, and that the former carried pneuma while the latter carried the blood. In other words, arteries delivered vital heat to the organs. When the pneuma reached the brain and heart, it generated thought and action; veins just delivered nourishment.

It took almost 2000 years for the existence of pneuma to be seriously challenged. Around 1508, Leonardo da Vinci wrote, “All the veins and arteries arise from the heart. And the reason is that the largest veins and arteries are found at their conjunction with the heart, and the further they are removed from the heart, the finer they become, dividing into very small branches.” In 1628 William Harvey (1578-1657) demonstrated that arteries and veins were both part of the same circulatory system, disproving pneuma once and for all.

3. COMMON SENSE

Now it's a metaphor, but common sense started out as a physical organ. Aristotle believed there was a spot near the heart where all the data from the senses was interpreted and adjudicated. The sense organs perceived information about the person's environment. That information was carried, probably by the blood, to a single central faculty called the sensus communis. The sensus communis then processed the information and converted it into a reaction or understanding.

Galen agreed with the concept, but he thought the sensory information was transmitted by the pneuma, not the blood, through hollow sensory nerves to the brain, not to the heart. The brain would then pump the pneuma into motor nerves and from there into muscles where the information became movement. Since Galen was held to be an unimpeachable source on medical matters well into the Renaissance, people kept on looking for the sensus communis in the brain until anatomists in the 17th century studied enough actual human brains to conclude that there was no such thing as the common sense.

4. AND 5. DEMONS AND GHOSTS

The earliest surviving medical texts are Sumerian cuneiform tablets engraved around 2100 BCE. By then, Mesopotamian medical precepts that disease (as opposed to injury) was caused by an irate god or demon possession were already firmly established. There were two kinds of healers: the ashipu, or exorcist, and the asu, or physician/pharmacist. The ashipu diagnosed the patient by determining which god or demon was causing the illness, and performed the incantations necessary to drive out the possessing spirit. The asu treated wounds and prescribed herbal remedies. Sometimes they worked together.

Demonic or ghostly possession as a physical invasion of the body causing a panoply of symptoms from seizures to self-harm to glossolalia carried forward into Jewish and later Christian tradition. There are exorcisms in the Dead Sea Scrolls and the New Testament. Jewish writings from the Middle Ages and early modern era report demons or dybbuks (spirits of the dead) physically leaving the body of the possessed through bloody fingernails or toenails, or in worst case scenarios, from the throat, vagina, or rectum.

6. HOMUNCULUS

Antonie van Leeuwenhoek, the father of microbiology, was the first person to examine seminal fluid under a microscope and discovered spermatozoa in 1677. He postulated that "a human being originates not from an egg but from an animalcule that is found in the male semen." Animalcules was the old-timey word for single-celled animals that people suddenly realized the world was crawling with once microscopes became popular.

Leeuwenhoek's student Nicolaas Hartsoeker, later inventor of the screw-barrel microscope, claimed to have made the discovery a few years earlier. There was a dispute between them over who got there first, but Leeuwenhoek was the boss, so he gets the credit. Hartsoeker didn't actually see any wee people curled up in sperm, but unlike Leeuwenhoek, he came to advocate the preformatist spermist position, i.e., that the miniature baby is already in the sperm before it gets anywhere near a uterus and that the woman only contributes the growing environment. He called it the "homunculus," from an alchemical term for a tiny full-grown person created by arcane means.

7. BOSOM SERPENT

The term bosom serpent was made famous by Nathaniel Hawthorne as the title of an 1843 short story about a man convinced that there's a snake living inside his chest. The idea that a snake, lizard, or assorted amphibians could be squirming around inside a person's body far predates Hawthorne, however, in folklore from all over the world.

In 1910, folklorist Thomas Johnson Westropp recorded a story from Clonlara, County Clare, Ireland, of a "worm with legs" running down a sleeping man's throat. Over time his appetite increased to alarming levels until he was compelled to consult a "wise person." The wise man told him to drink nothing and eat only bacon for two days. Then he was taken near a stream and his mouth pried open. When a rasher of crispy bacon was held to his mouth, the worm with legs ran out of his mouth and jumped on the bacon. The wise person threw the lizard bacon into the water and the patient was cured.

A certain Dr. Gardner, "Inventor of the Universal Medicines," announced his arrival in the Leeds Intelligencer of July 20, 1801, with guarantees that his nostrums could cure any number of ailments, including parasitic worms. Nothing remarkable there, but he also promised to show visitors more unusual beasts that he removed from afflicted patients: "One like a Lizard, the other has a Mouth like a Place, a Horn like a Snail, Two Ears like a Mouse, and its Body covered with Hair, was destroying the Man's Liver, a Portion of which it has brought off with it."

8. COMBINATION GUT CRITTERS AND DEMON POSSESSION

Theodorus Döderlein was 12 years old when he was stricken with terrible stomach cramps. The boy—who was the son of a pastor in Berolzheim, Germany—soon began to vomit streams of critters. He started off with insects and other invertebrates, and would go on to upchuck 21 newts, four frogs, and several toads. His doctor doubted it was really possible for so many animals to live comfortably inside the human stomach, but the local pastors were convinced it was real and caused by demonic possession. They didn't change their minds even when a doctor dissected one of the frogs and found partially digested insects in its stomach, suggesting the poor creature had eaten a fresh meal out of doors in the recent past.

The exorcists took over. There was report of a snake's head coming out of the boy's mouth during the ritual only to rush back down to the comfort of his gut when they tried to pull it out. With Theodorus still mired in invasive reptiles, amphibians, and insects, the exorcists decided to employ a surefire remedy for animals in the stomach: Horse urine. And lots of it. Accompanied by prayers and hymns, they poured multiple bottles of horse piss down naughty Theo's gullet. It worked like a charm. Theodorus never vomited up a single animal ever again.

9. BULUK'SIT ("BULGING EYE WORM")

The Tzeltal people in the highlands of Chiapas, Mexico, have an ancient medical tradition that goes back to the Maya. Body invaders play a significant role in this belief system. The Buluk'sit, or bulging eye worm, is one of the most insidious. It's a caterpillar about 3 inches long with horns and a large mouth for sucking like a leech or lamprey. It enters a woman's body through the vagina and takes up residence in the uterus. Every midnight it suckles from the womb, drawing nourishment from its unwitting "mother" as if it were a human fetus. This condemns the woman to infertility because all of the life force that would otherwise go to her possible baby is sucked away by the horned caterpillar. But some Tzeltal say that the caterpillar eats semen, and prevents pregnancy that way.

10. POKOK ("FROG")

In the same family of Tzeltal is the pokok syndrome, in which a frog is implanted by sorcery into the uterus of a woman where it grows as if it were a genuine pregnancy, only to end in the miscarriage of a malformed frog-like fetus.

BONUS: OK, THIS ONE MIGHT HAVE BEEN FOR REAL, THOUGH

Russian agriculturist and prolific memoirist Andrey Bolotov (1738-1833) told how a Russian peasant woman came to him with a bloated stomach. She claimed a koldun, or male sorcerer, had put a toad in her stomach. Bolotov wrote off her story as superstition and gave her an emetic to help her bring up whatever was causing her bloat. She vomited a toad. A live toad. Astounded, Bolotov examined the animal and found it was blind with atrophied rear legs as if it had lived in a dark, confined space for a long time.

10 of the Best Indoor and Outdoor Heaters on Amazon

Mr. Heater/Amazon
Mr. Heater/Amazon

With the colder months just around the corner, you might want to start thinking about investing in an indoor or outdoor heater. Indoor heaters not only provide a boost of heat for drafty spaces, but they can also be a money-saver, allowing you to actively control the heat based on the rooms you’re using. Outdoor heaters, meanwhile, can help you take advantage of cold-weather activities like camping or tailgating without having to call it quits because your extremities have gone numb. Check out this list of some of Amazon’s highest-rated indoor and outdoor heaters so you can spend less time shivering this winter and more time enjoying what the season has to offer.

Indoor Heaters

1. Lasko Ceramic Portable Heater; $20

Lasko/Amazon

This 1500-watt heater from Lasko may only be nine inches tall, but it can heat up to 300 square feet of space. With 11 temperature settings and three quiet settings—for high heat, low heat, and fan only—it’s a dynamic powerhouse that’ll keep you toasty all season long.

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2. Alrocket Oscillating Space Heater; $25

Alrocket/Amazon

Alrocket’s oscillating space heater is an excellent addition to any desk or nightstand. Using energy-saving ceramic technology, this heater is made of fire-resistant material, and its special “tip-over” safety feature forces it to turn off if it falls over (making it a reliable choice for homes with kids or pets). It’s extremely quiet, too—at only 45 dB, it’s just a touch louder than a whisper. According to one reviewer, this an ideal option for a “very quiet but powerful” heater.

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3. De’Longhi Oil-Filled Radiator Space Heather; $79

De’Longhi/Amazon

If you prefer a space heater with a more old-fashioned vibe, this radiator heater from De’Longhi gives you 2020 technology with a vintage feel. De’Longhi’s heater automatically turns itself on when the temperatures drops below 44°F, and it will also automatically turn itself off if it starts to overheat. Another smart safety feature? The oil system is permanently sealed, so you won’t have to worry about accidental spills.

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4. Aikoper Ceramic Tower Heater; $70

Aikoper/Amazon

Whether your room needs a little extra warmth or its own heat source, Aikoper’s incredibly precise space heater has got you covered. With a range of 40-95°F, it adjusts by one-degree intervals, giving you the specific level of heat you want. It also has an option for running on an eight-hour timer, ensuring that it will only run when you need it.

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5. Isiler Space Heater; $37

Isiler/Amazon

For a space heater that adds a fun pop of color to any room, check out this yellow unit from Isiler. Made from fire-resistant ceramic, Isiler’s heater can start warming up a space within seconds. It’s positioned on a triangular stand that creates an optimal angle for hot air to start circulating, rendering it so effective that, as one reviewer put it, “This heater needs to say ‘mighty’ in its description.”

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Outdoor Heaters

6. Mr. Heater Portable Buddy; $104

Mr. Heater/Amazon

Make outdoor activities like camping and grilling last longer with Mr. Heater’s indoor/outdoor portable heater. This heater can connect to a propane tank or to a disposable cylinder, allowing you to keep it in one place or take it on the go. With such a versatile range of uses, this heater will—true to its name—become your best buddy when the temperature starts to drop.

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7. Hiland Pyramid Patio Propane Heater; Various

Hiland/Amazon

The cold’s got nothing on this powerful outdoor heater. Hiland’s patio heater has a whopping 40,000 BTU output, which runs for eight to 10 hours on high heat. Simply open the heater’s bottom door to insert a propane tank, power it on, and sit back to let it warm up your backyard. The bright, contained flame from the propane doubles as an outdoor light.

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8. Solo Stove Bonfire Pit; $345

Solo Stove/Amazon

This one is a slight cheat since it’s a bonfire pit and not a traditional outdoor heater, but the Solo Stove has a 4.7-star rating on Amazon for a reason. Everything about this portable fire pit is meticulously crafted to maximize airflow while it's lit, from its double-wall construction to its bottom air vents. These features all work together to help the logs burn more completely while emitting far less smoke than other pits. It’s the best choice for anyone who wants both warmth and ambiance on their patio.

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9. Dr. Infrared Garage Shop Heater; $119

Dr. Infrared/Amazon

You’ll be able to use your garage or basement workshop all season long with this durable heater from Dr. Infrared. It’s unique in that it includes a built-in fan to keep warm air flowing—something that’s especially handy if you need to work without wearing gloves. The fan is overlaid with heat and finger-protectant grills, keeping you safe while it’s powered on.

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10. Mr. Heater 540 Degree Tank Top; $86

Mr. Heater/Amazon

Mr. Heater’s clever propane tank top automatically connects to its fuel source, saving you from having to bring any extra attachments with you on the road. With three heat settings that can get up to 45,000 BTU, the top can rotate 360 degrees to give you the perfect angle of heat you need to stay cozy. According to a reviewer, for a no-fuss outdoor heater, “This baby is super easy to light, comes fully assembled … and man, does it put out the heat.”

Buy it: Amazon

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A Brief History of Mashed Potatoes

mphillips007/iStock via Getty Images Plus
mphillips007/iStock via Getty Images Plus

During the Seven Years War of the mid-1700s, a French army pharmacist named Antoine-Augustin Parmentier was captured by Prussian soldiers. As a prisoner of war, he was forced to live on rations of potatoes. In mid-18th century France, this would practically qualify as cruel and unusual punishment: potatoes were thought of as feed for livestock, and they were believed to cause leprosy in humans. The fear was so widespread that the French passed a law against them in 1748.

But as Parmentier discovered in prison, potatoes weren’t deadly. In fact, they were pretty tasty. Following his release at the end of the war, the pharmacist began to proselytize to his countrymen about the wonders of the tuber. One way he did this was by demonstrating all the delicious ways it could be served, including mashed. By 1772, France had lifted its potato ban. Centuries later, you can order mashed potatoes in dozens of countries, in restaurants ranging from fast food to fine dining.

The story of mashed potatoes takes 10,000 years and traverses the mountains of Peru and the Irish countryside; it features cameos from Thomas Jefferson and a food scientist who helped invent a ubiquitous snack food. Before we get to them, though, let’s go back to the beginning.

The Origins of the Potato

Potatoes aren’t native to Ireland—or anywhere in Europe, for that matter. They were most likely domesticated in the Andes mountains of Peru and northwest Bolivia, where they were being used for food at least as far back as 8000 BCE.

These early potatoes were very different from the potatoes we know today. They came in a variety of shapes and sizes and had a bitter taste that no amount of cooking could get rid of. They were also slightly poisonous. To combat this toxicity, wild relatives of the llama would lick clay before eating them. The toxins in the potatoes would stick to the clay particles, allowing the animals to consume them safely. People in the Andes noticed this and started dunking their potatoes in a mixture of clay and water—not the most appetizing gravy, perhaps, but an ingenious solution to their potato problem. Even today, when selective breeding has made most potato varieties safe to eat, some poisonous varieties can still be bought in Andean markets, where they're sold alongside digestion-aiding clay dust.

By the time Spanish explorers brought the first potatoes to Europe from South America in the 16th century, they had been bred into a fully edible plant. It took them a while to catch on overseas, though. By some accounts, European farmers were suspicious of plants that weren’t mentioned in the Bible; others say it was the fact that potatoes grow from tubers, rather than seeds.

Modern potato historians debate these points, though. Cabbage’s omission from the Bible didn’t seem to hurt its popularity, and tulip cultivation, using bulbs instead of seeds, was happening at the same time. It may have just been a horticultural problem. The South American climates potatoes thrived in were unlike those found in Europe, especially in terms of hours of daylight in a day. In Europe, potatoes grew leaves and flowers, which botanists readily studied, but the tubers they produced remained small even after months of growing. This particular problem began to be remedied when the Spanish started growing potatoes on the Canary Islands, which functioned as a sort of middle ground between equatorial South America and more northerly European climes.

It’s worth pointing out, though, that there is some evidence for the cultural concerns mentioned earlier. There are clear references to people in the Scottish Highlands disliking that potatoes weren’t mentioned in the Bible, and customs like planting potatoes on Good Friday and sometimes sprinkling them with holy water suggest some kind of fraught relationship to potato consumption. They were becoming increasingly common, but not without controversy. As time went on, concerns about potatoes causing leprosy severely damaged their reputation.

Early Mashed Potato Recipes

A handful of potato advocates, including Parmentier, were able to turn the potato's image around. In her 18th-century recipe book The Art of Cookery, English author Hannah Glasse instructed readers to boil potatoes, peel them, put them into a saucepan, and mash them well with milk, butter, and a little salt. In the United States, Mary Randolph published a recipe for mashed potatoes in her book, The Virginia Housewife, that called for half an ounce of butter and a tablespoon of milk for a pound of potatoes.

But no country embraced the potato like Ireland. The hardy, nutrient-dense food seemed tailor-made for the island’s harsh winters. And wars between England and Ireland likely accelerated its adaptation there; since the important part grows underground, it had a better chance of surviving military activity. Irish people also liked their potatoes mashed, often with cabbage or kale in a dish known as colcannon. Potatoes were more than just a staple food there; they became part of the Irish identity.

But the miracle crop came with a major flaw: It’s susceptible to disease, particularly potato late blight, or Phytophtora infestans. When the microorganism invaded Ireland in the 1840s, farmers lost their livelihoods and many families lost their primary food source. The Irish Potato Famine killed a million people, or an eighth of the country’s population. The British government, for its part, offered little support to its Irish subjects.

One unexpected legacy of the Potato Famine was an explosion in agricultural science. Charles Darwin became intrigued by the problem of potato blight on a humanitarian and scientific level; he even personally funded a potato breeding program in Ireland. His was just one of many endeavors. Using potatoes that had survived the blight and new South American stock, European agriculturists were eventually able to breed healthy, resilient potato strains and rebuild the crop’s numbers. This development spurred more research into plant genetics, and was part of a broader scientific movement that included Gregor Mendel’s groundbreaking work with garden peas.

Tools of the Mashed Potato Trade

Around the beginning of the 20th century, a tool called a ricer started appearing in home kitchens. It’s a metal contraption that resembles an oversized garlic press, and it has nothing to do with making rice. When cooked potatoes get squeezed through the tiny holes in the bottom of the press, they’re transformed into fine, rice-sized pieces.

The process is a lot less cumbersome than using an old-fashioned masher, and it yields more appetizing results. Mashing your potatoes into oblivion releases gelatinized starches from the plant cells that glom together to form a paste-like consistency. If you’ve ever tasted “gluey” mashed potatoes, over-mashing was likely the culprit. With a ricer, you don’t need to abuse your potatoes to get a smooth, lump-free texture. Some purists argue that mashed potatoes made this way aren’t really mashed at all—they’re riced—but let's not let pedantry get in the way of delicious carbohydrates.

The Evolution of Instant Mashed Potatoes

If mashed potato pedants have opinions about ricers, they’ll definitely have something to say about this next development. In the 1950s, researchers at what is today called the Eastern Regional Research Center, a United States Department of Agriculture facility outside of Philadelphia, developed a new method for dehydrating potatoes that led to potato flakes that could be quickly rehydrated at home. Soon after, modern instant mashed potatoes were born.

It’s worth pointing out that this was far from the first time potatoes had been dehydrated. Dating back to at least the time of the Incas, chuño is essentially a freeze-dried potato created through a combination of manual labor and environmental conditions. The Incas gave it to soldiers and used it to guard against crop shortages.

Experiments with industrial drying were gearing up in the late 1700s, with one 1802 letter to Thomas Jefferson discussing a new invention where you grated the potato and pressed all the juices out, and the resulting cake could be kept for years. When rehydrated it was “like mashed potatoes” according to the letter. Sadly, the potatoes had a tendency to turn into purple, astringent-tasting cakes.

Interest in instant mashed potatoes resumed during the Second World War period, but those versions were a soggy mush or took forever. It wasn’t until the ERRC’s innovations in the 1950s that a palatable dried mashed potato could be produced. One of the key developments was finding a way to dry the cooked potatoes much faster, minimizing the amount of cell rupture and therefore the pastiness of the end-product. These potato flakes fit perfectly into the rise of so-called convenience foods at the time, and helped potato consumption rebound in the 1960s after a decline in prior years.

Instant mashed potatoes are a marvel of food science, but they’re not the only use scientists found for these new potato flakes. Miles Willard, one of the ERRC researchers, went on to work in the private sector, where his work helped contribute to new types of snacks using reconstituted potato flakes—including Pringles.