The Black Death is notable for wiping out much of the population of continental Europe. It was a terrible, devastating, and protracted event that was no doubt traumatic for those who managed to survive it.

But did you know that it led directly to the average person having a say in how they are ruled? With a shortage of workers, peasants found themselves with considerably more bargaining power. Migration patterns changed and different towns and cities grew out of the wreckage.

It's wild to think about: If the plague had not happened, would we all still be serfs?

But the Black Death isn't the only historical event with a macabre silver lining. People shared their thoughts with us after Redditor follopie asked the online community,

"What are some of the 'necessary evils' of history?"

"Allowing some attacks..."

"Allowing some attacks to take place even after Hitler's Enigma encryption device was cracked by the English and they knew when and where the attacks would occur. They could only act on the intelligence to thwart attacks if they could quickly come up with an alternate way to find out which the Germans would find believable."

wanted-to-upvote

To which this person replied:

"Neal Stephenson's book Cryptonomicon really does a great job of explaining this concept. Bounces back and forth between WWII and current day (well, ten or so years ago) drawing parallels between cryptography at the beginning of computers and encryption now."

countryhacker

"The only ways schools could get human bodies legally..."

"Body snatching in the 19th century."

"Medical schools would illegally buy human bodies that were dug up from graves in order to study anatomy and teach medical students in secret, because at the time it was illegal and not acceptable to use human bodies for Science or education purposes."

"The only way schools could get human bodies legally was from death-sentenced people who also had been condemned to dissection on top of that by the courts, which was very rare and couldn't supply enough bodies for medical schools."

"So there was a literal black market of dead bodies and the body snatchers would risk death penalty themselves to make profit from digging up bodies that were freshly buried. The bodies of young adult people were particularly sought after and expensive."

"But it also allowed scientists and students to learn about anatomy and improve surgery techniques, which allowed medicine as a whole to make a lot of progress and saved many lives in the end."

cocOtte

To which this person replied:

"This reminds me of the ethics dilemma around the use of data acquired from Nazi human experimentation. Or data acquired from 'testing' at Unit 731."

"Do we keep the data? Or toss it because we acquired it in a really f**ked up way?"

TheRockObama

"They have been instrumental..."

"One of the necessary evils through history has to be the experimentation on animals, specifically mice. They have been instrumental in our understanding of diseases."

Killdozah

To which this person replied:

"There's a pretty cool statue in Russia, honoring lab mice."

Zombiehacker595

"There's a school of thought..."

"Possibly the Agricultural Revolution."

"There's a school of thought that argues that it led to a diminished diet and poorer health for everyone, greater social inequality between classes and gender, and greater instances of warfare between and within sedentary and nomadic societies. So life really sucked for countless generations of humans for thousands of years."

"And yet it created the conditions for a population boom and the division of labour needed for humans to get really, really good at more specialized trades, skills, and learning, and here we are."

SodarnHinsane

To which this person replied:

"I feel like all you really need to do to negate the negative effects of modern society etc. is restructure cities to allow more natural things around us."

accomplishedpilot2

"All the people..."

"All the people that died trying berries, mushrooms, and other foods to see if they were poisonous. Somebody had to do it."

OneTyler2Many

To which this person replied:

"It truly sucked to be them."

[deleted]

"World War II..."

"World War II is controversial but it was the main factor why there has never been a major war since."

Starlight3020

To which this person replied:

"That and more importantly nuclear weapons. Even if Hiroshima and Nagasaki weren’t the main reason Japan surrendered, the fear of nuclear warfare has all but eliminated conflict between major powers in the 80+ years of relative peace."

YoungPacofgbm

"Starting a world war..."

"Starting a world war over the invasion of Poland. Sanctions against Libya. The killing of Osama bin Laden."

Rudaur

To which this person replied:

"Fair. Absolutely fair."

[deleted]

"Most wars..."

"Most wars lead to technological and medical advancements that likely never would have occurred without war."

llcuff80

To which this person replied:

"There is a concept called opportunity cost in economics. In a world of limited resources, it means that resources invested in one thing are resources not invested in something else. Whatever you do, there's always a tradeoff."

"War doesn't cause technological advancements to occur, it just directs those advancements towards certain goals."

Ellakastekat

"Dinosaurs..."

"Dinosaurs had to go for mammals to rise up as the dominant order on Earth."

Drakisright

To which this person replied:

"Earth would have been better if the dinosaurs continued being the dominant species."

CyclonsInaPoliceBox

"It broke the back..."

"Sherman's March. It broke the back of the Confederacy. Scorched Earth but at quite the cost."

Krd167

To which this person replied:

"In his own words: 'War is cruelty. There is no use trying to reform it. The crueler it is, the sooner it will be over.'"

Whiteshark49

The world is not black and white. It exists, in fact, in certain shades of gray. Something to think about as we continue to reap the benefits of modern-day living.

Have some observations of your own? Feel free to tell us more in the comments below!

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