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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
Hanns Hörbiger.
Public domain
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.
Public domain
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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How New York's largest hospital system is predicting COVID-19 spikes
Northwell Health is using insights from website traffic to forecast COVID-19 hospitalizations two weeks in the future.
- The machine-learning algorithm works by analyzing the online behavior of visitors to the Northwell Health website and comparing that data to future COVID-19 hospitalizations.
- The tool, which uses anonymized data, has so far predicted hospitalizations with an accuracy rate of 80 percent.
- Machine-learning tools are helping health-care professionals worldwide better constrain and treat COVID-19.
The value of forecasting
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Credit: Northwell Health
<p>One unique benefit of forecasting COVID-19 hospitalizations is that it allows health systems to better prepare, manage and allocate resources. For example, if the tool forecasted a surge in COVID-19 hospitalizations in two weeks, Northwell Health could begin:</p><ul><li>Making space for an influx of patients</li><li>Moving personal protective equipment to where it's most needed</li><li>Strategically allocating staff during the predicted surge</li><li>Increasing the number of tests offered to asymptomatic patients</li></ul><p>The health-care field is increasingly using machine learning. It's already helping doctors develop <a href="https://care.diabetesjournals.org/content/early/2020/06/09/dc19-1870" target="_blank">personalized care plans for diabetes patients</a>, improving cancer screening techniques, and enabling mental health professionals to better predict which patients are at <a href="https://healthitanalytics.com/news/ehr-data-fuels-accurate-predictive-analytics-for-suicide-risk" target="_blank" rel="noopener noreferrer">elevated risk of suicide</a>, to name a few applications.</p><p>Health systems around the world have already begun exploring how <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7315944/" target="_blank" rel="noopener noreferrer">machine learning can help battle the pandemic</a>, including better COVID-19 screening, diagnosis, contact tracing, and drug and vaccine development.</p><p>Cruzen said these kinds of tools represent a shift in how health systems can tackle a wide variety of problems.</p><p>"Health care has always used the past to predict the future, but not in this mathematical way," Cruzen said. "I think [Northwell Health's new predictive tool] really is a great first example of how we should be attacking a lot of things as we go forward."</p>Making machine-learning tools openly accessible
<p>Northwell Health has made its predictive tool <a href="https://github.com/northwell-health/covid-web-data-predictor" target="_blank">available for free</a> to any health system that wishes to utilize it.</p><p>"COVID is everybody's problem, and I think developing tools that can be used to help others is sort of why people go into health care," Dr. Cruzen said. "It was really consistent with our mission."</p><p>Open collaboration is something the world's governments and health systems should be striving for during the pandemic, said Michael Dowling, Northwell Health's president and CEO.</p><p>"Whenever you develop anything and somebody else gets it, they improve it and they continue to make it better," Dowling said. "As a country, we lack data. I believe very, very strongly that we should have been and should be now working with other countries, including China, including the European Union, including England and others to figure out how to develop a health surveillance system so you can anticipate way in advance when these things are going to occur."</p><p>In all, Northwell Health has treated more than 112,000 COVID patients. During the pandemic, Dowling said he's seen an outpouring of goodwill, collaboration, and sacrifice from the community and the tens of thousands of staff who work across Northwell.</p><p>"COVID has changed our perspective on everything—and not just those of us in health care, because it has disrupted everybody's life," Dowling said. "It has demonstrated the value of community, how we help one another."</p>3,000-pound Triceratops skull unearthed in South Dakota
"You dream about these kinds of moments when you're a kid," said lead paleontologist David Schmidt.
Excavation of a triceratops skull in South Dakota.
- The triceratops skull was first discovered in 2019, but was excavated over the summer of 2020.
- It was discovered in the South Dakota Badlands, an area where the Triceratops roamed some 66 million years ago.
- Studying dinosaurs helps scientists better understand the evolution of all life on Earth.
Credit: David Schmidt / Westminster College
<p style="margin-left: 20px;">"We had to be really careful," Schmidt told St. Louis Public Radio. "We couldn't disturb anything at all, because at that point, it was under law enforcement investigation. They were telling us, 'Don't even make footprints,' and I was thinking, 'How are we supposed to do that?'"</p><p>Another difficulty was the mammoth size of the skull: about 7 feet long and more than 3,000 pounds. (For context, the largest triceratops skull ever unearthed was about <a href="https://www.tandfonline.com/doi/abs/10.1080/02724634.2010.483632" target="_blank">8.2 feet long</a>.) The skull of Schmidt's dinosaur was likely a <em>Triceratops prorsus, </em>one of two species of triceratops that roamed what's now North America about 66 million years ago.</p>Credit: David Schmidt / Westminster College
<p>The triceratops was an herbivore, but it was also a favorite meal of the T<em>yrannosaurus rex</em>. That probably explains why the Dakotas contain many scattered triceratops bone fragments, and, less commonly, complete bones and skulls. In summer 2019, for example, a separate team on a dig in North Dakota made <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">headlines</a> after unearthing a complete triceratops skull that measured five feet in length.</p><p>Michael Kjelland, a biology professor who participated in that excavation, said digging up the dinosaur was like completing a "multi-piece, 3-D jigsaw puzzle" that required "engineering that rivaled SpaceX," he jokingly told the <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">New York Times</a>.</p>Morrison Formation in Colorado
James St. John via Flickr
Triceratops illustration
Credit: Nobu Tamura/Wikimedia Commons |
World's oldest work of art found in a hidden Indonesian valley
Archaeologists discover a cave painting of a wild pig that is now the world's oldest dated work of representational art.
Pig painting at Leang Tedongnge in Indonesia, made at 45,500 years ago.
- Archaeologists find a cave painting of a wild pig that is at least 45,500 years old.
- The painting is the earliest known work of representational art.
- The discovery was made in a remote valley on the Indonesian island of Sulawesi.
Oldest Cave Art Found in Sulawesi
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="a9734e306f0914bfdcbe79a1e317a7f0"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/b-wAYtBxn7E?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>What can Avicenna teach us about the mind-body problem?
The Persian polymath and philosopher of the Islamic Golden Age teaches us about self-awareness.
The incredible physics behind quantum computing
Can computers do calculations in multiple universes? Scientists are working on it. Step into the world of quantum computing.
