Ask HN: What are examples of common beliefs conclusively invalidated by data?

In America: "Don't swim for 30 minutes after eating or you will cramp" "You should be drinking 8 glasses of water a day" In Korea: "Sleeping with a fan on is dangerous as it will steal your breath"

"The world is getting worse" is a belief perpetuated by the media and repeated by many people to explain their own unhappiness. However, many important indicators show things are getting better globally https://www.vox.com/2014/11/24/7272929/global-poverty-health...

https://en.wikipedia.org/wiki/List_of_common_misconceptions should get you started.

Homeopathy.

The Flaw of Averages states that: Plans based on the assumption that average conditions will occur are wrong on average.

https://news.stanford.edu/pr/00/flawaverages1025.html

Vaccines causing autism seems like a good example. The original studies about this were fraudulent/wrong, and their effects have basically never been replicated since.

Also that of people only using 10% of their brain, since it's more accurate that people use different parts of their brains at different times. No, using 100% wouldn't give you psychic powers or make you superhuman or whatever else some works of fiction and new age mystics might posit.

GMO is harmful: https://en.wikipedia.org/wiki/Genetically_modified_food#Heal...

Bio/organic food is healthier than the regular food: https://en.wikipedia.org/wiki/Organic_food#Health_and_safety

Covid vaccine hesitancy is a good example.

That in most cases diversity is not a strength.

- it brings negative performance when the diversity is age related

- it brings negative performance outside of tech/knowledge intensive jobs when it’s gender/ethnicity related

- Only educational diversity seems to bring positive results

Increased spending on health care results in average increased health outcomes (e.g. lower all-cause mortality).

"What doesn't kill you makes you stronger." After being hit by a truck, surviving cancer, returning from a long war, or losing a child, experience (data) teaches you otherwise.

A very recent one for me is that a lack of electrolytes is not a likely cause for cramps. The current science is still up in the air and the conclusion at the moment is "we still don't really know"

https://www.painscience.com/articles/cramps-spasms-twitches-...

Omnipotent beings.

The inverse is far easier, and I'd say even more interesting: common beliefs that are not conclusively supported by data.

'conclusively proven' is a high bar, particularly when paired with 'commonly'. If it has been conclusively proven false then why is it still commonly believed? It's pretty easy to say 'because I'm smarter than everyone else' but it's also a cop-out.

Can it be proven for every single person or living entity? Can it be proven for every location? Can it be proven for every time, every season, every year. You can show the minuscule odds that someone will win the lottery yet people do win lotteries. What can you prove?

That "learning styles" exist: https://digest.bps.org.uk/2021/02/04/the-learning-styles-myt...

https://www.educationnext.org/stubborn-myth-learning-styles-...

https://www.theatlantic.com/science/archive/2018/04/the-myth...

The "Wrecked by success" thing was just here yesterday, I think that fits your question?

https://news.ycombinator.com/item?id=31817677

Astrology/horoscopes https://en.m.wikipedia.org/wiki/Astrology_and_science

Hey, apparently the hot hand debate has been settled and there's actually solid evidence after all this time! [1] [2]

[1] https://statmodeling.stat.columbia.edu/?s=hot+hand&submit=Se... [2] https://statmodeling.stat.columbia.edu/2015/07/09/hey-guess-...

"The human eye can't see past 30fps"

Well with the advance of video gaming and high refresh rate displays that went out of the window quickly. Nowadays you even have 120hz displays on smartphones so easy to show someone the plain difference between 30fps and 120fps.

At home I have a 240hz monitor and even the difference between 144fps and 240fps is noticeable albeit not that big difference as between 30fps and higher ones.

Searing meat seals in the juices.

Wikipedia's only citation for this being false is a commercially published book[0], but there are various reports of experimental testing, e.g.:

https://www.seriouseats.com/perfect-prime-rib-beef-recipe

https://www.cooksillustrated.com/how_tos/5699-searing-steak

[0] McGee, Harold (1990), The Curious Cook: More Kitchen Science and Lore, page 13, "The Searing Truth"

People choose to do things to maximize happiness

https://www.inc.com/jessica-stillman/happiness-satisfaction-...

1. Trickle down economics, it just doesn't work.

2. Trans folks regretting transition, only 0.4% do. https://transequality.org/sites/default/files/docs/usts/USTS...

3. Vaccines causing long-term damages more than Covid while Covid causes long-covid with long term damages 1 in 10 times and vaccines cause long-term damages 1 in 100,000 times.

4. Republican presidents being a good thing, they have a horrible economic track record, completely wreck the country every single time and Democractic presidents spend their terms building them back up until the next Republican president comes. https://itdoesnotaddup.files.wordpress.com/2021/02/capture21...

Basically every major right-wing talking point. :D