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5 of history's strangest scientific theories
Rest assured: Kooky ideas like the Earth being flat or vaccines causing autism are nothing new. Humanity has had worse ideas before.
- The line between science and strongly held belief was not always so clear-cut as it is today.
- In the past, many quacks, charlatans, or well-intentioned philosophers have developed theories that strike us as obviously untrue today.
- But hindsight is 20/20: People really had no idea how the world actually worked in the past.
For most of us, it's easy to distinguish between real science and pseudoscience. Real science requires testing hypotheses, a rigorous analysis of the results, and peer review, after which the findings are either debunked, tweaked, or accepted as fact. Pseudoscience dresses itself up in the clothes of science but doesn't play by the same rules, particularly when it comes to abandoning ideas that fail to pass peer review.
But the difference between strongly held belief and scientific fact were not always so clear cut as they are today. The line between the two was blurry; if a belief had just enough of the trappings of evidence-based analysis, it could gain some traction. Over the course of history, some truly bizarre scientific theories have been put forward — here's five of the strangest.
1. World Ice Doctrine
In 1894, Austrian engineer Hanns Hörbiger observed that the moon was shiny and rough, much like ice. Then, he had a dream of himself floating in space, observing a swinging pendulum whose tether eventually broke. These two events were enough for him to develop his Welteislehre, or World Ice Doctrine.
The doctrine argued that ice is the fundamental building block of the universe, with icy celestial bodies and an icy ether that permeates the universe. This bizarre cosmological model wouldn't have gained any traction whatsoever were it not for two developments. First, after being completely dismissed by the scientific community, Hörbiger marketed his theories directly to the people, a tactic that has led to the unnatural long life of many pseudoscientific theories. Second, the Nazis came to power.
The Nazis had expelled many scientists from Germany, particularly Jewish ones. Among these was Albert Einstein, whose theory of relativity was not well-regarded amongst the Nazi community. World Ice Doctrine served as an alternative cosmological model. Both Adolf Hitler and Heinrich Himmler, one of the more occult-leaning Nazis, were notable proponents of the theory.
2. Milk transfusions
Before blood types were discovered in 1901, many physicians believed that it would be far more useful to direct their energies toward finding a blood substitute rather than to try the risky procedure of transfusing human blood to patients. So, in 1854, Toronto Drs. James Bovell and Edwin Hodder injected a 40-year-old man with 12 ounces of cow's milk.
The belief was that the fatty particles in milk would become "white corpuscles," which we refer to today as white blood cells. This was not the case. Despite this, milk transfusions remained a relatively popular area of research and experimentation until about 1884. There were some successes at least in the sense that the patient did not die, but these were likely due to the small quantities of milk used in the procedure.
3. Dr. Henry Cotton's... unique approach to mental illness
An illustration from Henry Cotton's "The Defective Delinquent and Insane" depicted a mentally ill individual's mouth with teeth removed.
Without a doubt the inventor of one of the strangest and most macabre ideas on this list, Dr. Henry Cotton had developed a radical theory of insanity that he used to "treat" patients between 1907 and 1930 as the medical director of the New Jersey State Hospital at Trenton. His theory was that mental illness came about due to physical infections, particularly in the teeth. The solution? Pull them out! Under Cotton's direction, 11,000 teeth were extracted from mentally ill patients.
When patients failed to improve after this, Cotton theorized that the infection must have spread to other organs. The natural conclusion was to remove these as well, which he did on 645 separate occasions. Though Cotton claimed an 80 percent success rate at treating mental illness — and actually became quite popular due to this fabricated figure — his mortality rate was astronomical, and patients (unsurprisingly) actually did better when they were not treated by Cotton.
At the very least, Cotton was a true believer in his theory. He removed several of his own teeth, and those of his wife and children. He also found dentists to be extremely peculiar since they focused on fixing teeth rather than pulling them out.
4. The spontaneous generation of life
Originally developed by Aristotle, the theory of spontaneous generation persisted only until Louis Pasteur disproved it in the mid-19th century. In essence, it declared that life could and regularly did form from non-living matter spontaneously. Aristotle, for instance, claimed that scallops were generated from sand. Others made the observation that maggots grew in dead flesh — nobody ever saw maggots travel to dead flesh, and it took a surprisingly long time for people to understand that maggots were laid there by other flies.
To us today, the theory sounds obviously preposterous, but this just highlights how little ancient people really knew about the world until the scientific method became the norm. An idea that lasts for over 2,000 years must have some staying power. And if all you have is observation, it's not too crazy — life, after all, springs from apparently inert things like seeds all the time.
5. Samuel Cartwright's racial psychology
Samuel Cartwright was a physician practicing in the American South, who, in 1851, delivered a report to the Medical Association of Louisiana titled "Report on the Diseases and Physical Peculiarities of the Negro Race." Unsurprisingly, there was wild speculation contained within the report, notably his "discovery" of two conditions: drapetomania and dysaesthesia aethiopica.
Drapetomania, Cartwright claimed, was a sort of madness that affected black slaves, causing them to flee. He attributed this to slave owners treating their slaves as equals or by being overly harsh:
If the white man attempts to oppose the Deity's will, by trying to make the negro anything else than "the submissive knee-bender" (which the Almighty declared he should be) … or if he abuses the power which God has given him over his fellow-man, by being cruel to him … the negro will run away.
Cartwright's cure was to treat slaves as though they were children — meaning as lesser-than and occasionally subject to corporal punishment. For truly unresolvable cases, Cartwright had a horrifyingly straightforward cure: Cut off their big toes.
Dysaesthesia aethiopica, according to Cartwright, was a mental illness that caused slaves to be lazy. Cartwright claimed this illness was somehow connected to the skin, believing that the lesions he saw on lazy slaves were a manifestation of the illness. The cure for this illness was whipping. But of course, if a slave was seen as being lazy, he'd be more likely to be whipped, and if he were whipped more often, he'd probably develop some lesions. For the slave owners who followed Cartwright's logic, this ensured a perverse cycle of whippings.
This list is by no means exhaustive; human beings crave explanations for things, but they haven't always had the tools to come up with accurate ones. Even today, we're dubious of the claims of the scientific community. But so long as there's honest-to-goodness science, there will be sketchily crafted theories like the flat Earth theory, that dinosaurs were put in the ground by God 5,000 years ago, that vaccines cause autism, and many others.
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Evolution doesn't clean up after itself very well.
- An evolutionary biologist got people swapping ideas about our lingering vestigia.
- Basically, this is the stuff that served some evolutionary purpose at some point, but now is kind of, well, extra.
- Here are the six traits that inaugurated the fun.
The plica semilunaris<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NjgwMS9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY3NDg5NTg1NX0.kdBYMvaEzvCiJjcLEPgnjII_KVtT9RMEwJFuXB68D8Q/img.png?width=980" id="59914" width="429" height="350" data-rm-shortcode-id="b11e4be64c5e1f58bf4417d8548bedc7" data-rm-shortcode-name="rebelmouse-image" />
The human eye in alarming detail. Image source: Henry Gray / Wikimedia commons<p>At the inner corner of our eyes, closest to the nasal ridge, is that little pink thing, which is probably what most of us call it, called the caruncula. Next to it is the plica semilunairs, and it's what's left of a third eyelid that used to — ready for this? — blink horizontally. It's supposed to have offered protection for our eyes, and some birds, reptiles, and fish have such a thing.</p>
Palmaris longus<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NjgwNy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzMzQ1NjUwMn0.dVor41tO_NeLkGY9Tx46SwqhSVaA8HZQmQAp532xLxA/img.jpg?width=980" id="879be" width="1920" height="2560" data-rm-shortcode-id="4089a32ea9fbb1a0281db14332583ccd" data-rm-shortcode-name="rebelmouse-image" />
Palmaris longus muscle. Image source: Wikimedia commons<p> We don't have much need these days, at least most of us, to navigate from tree branch to tree branch. Still, about 86 percent of us still have the wrist muscle that used to help us do it. To see if you have it, place the back of you hand on a flat surface and touch your thumb to your pinkie. If you have a muscle that becomes visible in your wrist, that's the palmaris longus. If you don't, consider yourself more evolved (just joking).</p>
Darwin's tubercle<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NjgxMi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0ODUyNjA1MX0.8RuU-OSRf92wQpaPPJtvFreOVvicEwn39_jnbegiUOk/img.jpg?width=980" id="687a0" width="819" height="1072" data-rm-shortcode-id="ff5edf0a698e0681d11efde1d7872958" data-rm-shortcode-name="rebelmouse-image" />
Darwin's tubercle. Image source: Wikimedia commons<p> Yes, maybe the shell of you ear does feel like a dried apricot. Maybe not. But there's a ridge in that swirly structure that's a muscle which allowed us, at one point, to move our ears in the direction of interesting sounds. These days, we just turn our heads, but there it is.</p>
Goosebumps<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NzMxNC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyNzEyNTc2Nn0.aVMa5fsKgiabW5vkr7BOvm2pmNKbLJF_50bwvd4aRo4/img.jpg?width=980" id="d8420" width="1440" height="960" data-rm-shortcode-id="8827e55511c8c3aed8c36d21b6541dbd" data-rm-shortcode-name="rebelmouse-image" />
Goosebumps. Photo credit: Tyler Olson via Shutterstock<p>It's not entirely clear what purpose made goosebumps worth retaining evolutionarily, but there are two circumstances in which they appear: fear and cold. For fear, they may have been a way of making body hair stand up so we'd appear larger to predators, much the way a cat's tail puffs up — numerous creatures exaggerate their size when threatened. In the cold, they may have trapped additional heat for warmth.</p>
Tailbone<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NzMxNi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3MzQwMjc3N30.nBGAfc_O9sgyK_lOUo_MHzP1vK-9kJpohLlj9ax1P8s/img.jpg?width=980" id="9a2f6" width="1440" height="1440" data-rm-shortcode-id="4fe28368d2ed6a91a4c928d4254cc02a" data-rm-shortcode-name="rebelmouse-image" />
Image source: Decade3d-anatomy online via Shutterstock<p>Way back, we had tails that probably helped us balance upright, and was useful moving through trees. We still have the stump of one when we're embryos, from 4–6 weeks, and then the body mostly dissolves it during Weeks 6–8. What's left is the coccyx.</p>
The palmar grasp reflex<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NzMyMC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjY0MDY5NX0.OSwReKLmNZkbAS12-AvRaxgCM7zyukjQUaG4vmhxTtM/img.jpg?width=980" id="8804c" width="1440" height="960" data-rm-shortcode-id="67542ee1c5a85807b0a7e63399e44575" data-rm-shortcode-name="rebelmouse-image" />
Palmar reflex activated! Photo credit: Raul Luna on Flickr<p> You've probably seen how non-human primate babies grab onto their parents' hands to be carried around. We used to do this, too. So still, if you touch your finger to a baby's palm, or if you touch the sole of their foot, the palmar grasp reflex will cause the hand or foot to try and close around your finger.</p>
Other people's suggestions<p>Amir's followers dove right in, offering both cool and questionable additions to her list. </p>
Fangs?<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Lower mouth plate behind your teeth. Some have protruding bone under the skin which is a throw back to large fangs. Almost like an upsidedown Sabre Tooth.</p>— neil crud (@neilcrud66) <a href="https://twitter.com/neilcrud66/status/1085606005000601600?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Hiccups<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Sure: <a href="https://t.co/DjMZB1XidG">https://t.co/DjMZB1XidG</a></p>— Stephen Roughley (@SteBobRoughley) <a href="https://twitter.com/SteBobRoughley/status/1085529239556968448?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Hypnic jerk as you fall asleep<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">What about when you “jump” just as you’re drifting off to sleep, I heard that was a reflex to prevent falling from heights.</p>— Bann face (@thebanns) <a href="https://twitter.com/thebanns/status/1085554171879788545?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script> <p> This thing, often called the "alpha jerk" as you drop into alpha sleep, is properly called the hypnic jerk,. It may actually be a carryover from our arboreal days. The <a href="https://www.livescience.com/39225-why-people-twitch-falling-asleep.html" target="_blank" data-vivaldi-spatnav-clickable="1">hypothesis</a> is that you suddenly jerk awake to avoid falling out of your tree.</p>
Nails screeching on a blackboard response?<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Everyone hate the sound of fingernails on a blackboard. It's _speculated_ that this is a vestigial wiring in our head, because the sound is similar to the shrill warning call of a chimp. <a href="https://t.co/ReyZBy6XNN">https://t.co/ReyZBy6XNN</a></p>— Pet Rock (@eclogiter) <a href="https://twitter.com/eclogiter/status/1085587006258888706?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Ear hair<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Ok what is Hair in the ears for? I think cuz as we get older it filters out the BS.</p>— Sarah21 (@mimix3) <a href="https://twitter.com/mimix3/status/1085684393593561088?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Nervous laughter<blockquote class="twitter-tweet" data-lang="en"><p lang="en" dir="ltr">You may be onto something. Tooth-bearing with the jaw clenched is generally recognized as a signal of submission or non-threatening in primates. Involuntary smiling or laughing in tense situations might have signaled that you weren’t a threat.</p>— Jager Tusk (@JagerTusk) <a href="https://twitter.com/JagerTusk/status/1085316201104912384?ref_src=twsrc%5Etfw">January 15, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
Um, yipes.<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Sometimes it feels like my big toe should be on the side of my foot, was that ever a thing?</p>— B033? K@($ (@whimbrel17) <a href="https://twitter.com/whimbrel17/status/1085559016011563009?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
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