Going back all the way to ancient Rome, being a doctor was regarded as one of the lowliest of professions. Back then, the job of stitching people up after they were stabbed by a Hun or a Visigoth was relegated to people from the lowest rungs of society, like slaves or foreigners. Why? Well, there's the fact that until recently they were hugely unsuccessful at actually healing people.

The whole concept of having to get a medical license, or having to learn much of anything about how the body worked, is a pretty recent one (hell, doctors didn't even know to wash their goddamned hands before surgery until the mid-1800s). So, for centuries hospitals were where you went to die, and doctors were the butchers who hacked off your limbs with rusty tools before sending you home with some mercury to drink.

Franz Anton Maulbertsch
They could also give you a quick trim.

Putting all the king's horses and all the king's men back together again had always been seen as a vulgar profession. By the 18th century, doctors were put on the same rung of the social ladder as, say, barbers. In fact, a medical journal from that time once lamented that becoming a doctor was popularly considered to be throwing your life away, the same as if you tell your mother today, "I've decided to make my career reviewing video games on YouTube."

Then, as we approached the dawn of the 20th century, a number of advances came along to introduce the radical idea of patients actually making it home from the hospital alive. Governments started requiring doctors to learn that s**t before calling themselves doctors (though some rappers were grandfathered in) and suddenly people were willing to pay top dollar for their services. It's kind of like if next year a new discovery made it possible for psychics to actually see the future. Suddenly people would stop seeing them as back-alley hustlers, and every Ivy League school would have classes in that s**t.

Warner Bros
Even Hogwarts would have to take it seriously.

You'd be forgiven for assuming that the concept of prison is as old as the concept of crime. After all, we have stories from really old-timey times about princesses being locked in towers and people being condemned to brave dungeons and/or dragons. But although dungeons and prisons did exist to some extent, the concept of prison as a punishment for committing a crime is only as old as, oh, around the 1800s. Yes, that's A.D. 1800.

For most of history, the old lockup was used only to keep accused criminals from skipping town before their trial. When the punishments were actually handed out, they usually came in the form of something much more public and immediate than incarceration. Before the 19th century, sentences ranged from hanging for the worst offenses to flogging or public shaming for the less severe.

Smith College
Like assault, or women wearing pants.

As recently as the 18th century, it was common practice for criminals to be simply branded with their crime so that others would always be aware of what kind of a*****e they were. You might recognize this concept from Nathaniel Hawthorne's The Scarlet Letter (in which a woman is branded with the letter A for "adulterer"). Criminals of the time faced a veritable Sesame Street of brandings, such as B for "blasphemer," F for "fighter," and T for "thief." Seems like there are more crimes than letters, but whatever.

In fact, the nation of Australia owes its entire existence to the fact that Britain hadn't come up with the concept of prison yet well into the 1800s. Faced with the problem of an increasing number of criminals and ne'er-do-wells being rapped on the knuckles and sent back to rejoin society, Britain was thrilled with the discovery of an entirely new continent where they could send undesirable people far away from civilization. The fact that Australia pretty much has more deadly animals than it does dirt was just a bonus, making deportation a kind of cruel and unusual execution.

Totajla/iStock/Getty Images
And hot. It's so goddamn hot, you guys.

It was the U.S. that eventually came up with the idea of imprisonment as an alternative to death or banishment for criminals. In the 1830s, it became noted by European visitors that America handed down the death penalty for an astounding number of offenses, from murder to jaywalking. So, the U.S. started looking into humane alternatives to the go-to "death or torture" solution. Some bright spark came up with the idea of simply locking criminals up in a large stone building for several years instead of shooting them, which also gave birth to the concept of rehabilitation. The idea was that, given enough time to think about what they had done, the antisocial might once again become productive members of society. The jury is still out, so to speak, on whether locking criminals in a room with other criminals is the best way to produce saints.

As a result, the average work week at the time was around 50 hours. So, how did the workers of the world convince bosses to double their weekly vacation? Well, first, bosses started noticing that people would frequently just call in sick (or telegram in sick, as the case may have been) whenever they needed a personal day or had a hangover to attend to. But the other issue was that there were tensions between workers about the Sabbath day itself. See, Christians recognized the Sabbath on Sunday, but in Jewish tradition, it's Saturday. So if you had a mix of religions represented in your company's workforce, you were asking someone to violate their faith no matter which day you closed.

A solution as simple as it was brilliant was devised by automobile magnate Henry Ford -- in 1926 he decided to give everyone in his factories both Saturday and Sunday off, no matter their religion. As a staunch anti-Semite, we're betting he didn't do this out of compassion for his Jewish workers, but purely as a good business decision. His workers would stop squabbling over which day was technically the Sabbath and, he believed, they would spend most of their newfound leisure time taking their Ford automobiles out on long drives and picnics. Which would ultimately force them to spend more money repairing their s****y Ford automobiles.

via chronicle.com
Plus, it gave him extra time to hang out with Nazis.

Soon after, the Great Depression hit and the reduced work week was seen as purely a way to cut hours without having to lay off employees. Then the New Deal came along and the government set the work week at 40 hours, figuring that it would help create jobs (since it would be cheaper to hire more people than pay everybody overtime). The weekend was born.

And ... it's probably going to die soon -- already about a third of Americans work weekends thanks to the proliferation of service jobs in businesses that keep the doors open seven days a week. Hey, it was fun while it lasted.

Thinkstock Images/Stockbyte/Getty Images
"There's 168 hours in a week; I'm only asking for 70, you selfish p***k."

Speaking of which ...

Money has made the world go around ever since the moment some caveman discovered that he could acquire his neighbor's much nicer cave by giving him 20 rabbits for it, instead of simply killing him. So it's surprising to learn that, despite being one of humanity's oldest concepts, we didn't really know how money worked on a grand scale until the early 20th century.

When the Great Depression hit in the 1930s, it drove millions to ruin and made the Western world look like a post-apocalyptic society that skipped the apocalypse. And the thing is, at the time nobody knew why it happened. It wasn't like there were a whole bunch of political ideologues warning of a coming recession -- prices just started shooting up, incomes crashing down, and nobody could really explain why. Sure, people knew about concepts like banking panics, inflation, and the stock market. They just didn't know how all these things had conspired in such a way that they suddenly couldn't feed their children.

Paul Katz/Photodisc/Getty Images
Although, alchemy was popular well into the 19th century, so we're not even sure
they had the inflation bit figured out.

So, the government had to gather all their wizards together to chant over some goat entrails and figure out some way to measure the overall financial health of America so that they could see this coming next time. The result was the national income -- what's now known as the gross domestic product, or GDP -- and it was the first time we were able to put numbers to what's actually going on in the economy, instead of relying on whether or not a groundhog sees his shadow to determine if we're going to have six more weeks of horrendous poverty.

The report that these people who would eventually become known as "economists" submitted to Congress was so popular among the general population during the Depression that it became a New York Times bestseller. And, remember, this was a dry congressional report about economics, not some thriller that was sexed-up with zombies.

YekoPhotoStudio/iStock/Getty Images
"Braaaaains ... Reeeeduuuction in aggreeegaaaate demand."

The concept of GDP was so helpful in predicting the whims of the economy that it was soon adopted by pretty much the whole globe, which is why we haven't had any kind of global financial crisis ever since.

We previously pointed out that there are societies on Earth who, right now, have no concept of time. Obviously, they know the broad strokes -- if they're going to get water in "the morning" they know it's that time after the sun has come up. But tell one of these people to meet you at 10:15 a.m. and they'll just look at you like you're an a*****e. It's almost impossible to wrap your head around, but they're not the weird ones: The concept of refining time down to precise increments is very recent.

Sure, the concept of the hour is pretty old -- it came from the ancient Sumerians, who used 24 as their base counting system, instead of 10. That's because, instead of counting on their fingers, they counted on the knuckles on their digits, of which there are 12 on each hand (discounting the thumb, because that two-knuckled freak messes up the elegance of the whole system). So after the Sumerians decided there were 24 hours in a day, you'd expect that further subdivision into minutes and seconds would have followed fairly soon. But you'd be wrong -- we didn't really bother to come up with any unit of time smaller than an hour for thousands of years. Not until the invention of the goddamn locomotive, in fact.

Jupiterimages/Stockbyte/Getty Images
Popularly known as the "Dinosaur-Powered Explod-O-Mobile."

Before that, the time of day was measured by sundials, and that was enough. In the ancient and medieval world, most poor people were tilling fields and shoveling muck, and most rich people were sitting on thrones, gnawing on turkey legs, and occasionally throwing rocks at the poor people. Either way, nobody really needed to know what the time was more specifically than how many hours there were until sunset.

Although somebody along the way did come up with the concept of the minute, nobody really needed it -- in fact, when the first mechanical clocks and watches were invented most of them only had a single hand, for the hour. This is why, for example, Galileo had to drop a bunch of s**t from a great height to measure gravity before he had the luxury of being able to time his experiments.

"Marty, the lightning will hit the clock tower at precisely 10-ish!"

Finally, in the 1800s, when railway travel was becoming popular, people began to realize that a unit of time smaller than the hour was necessary in their daily lives. Since trains traveled much faster than horses, people needed some way to gauge the time of a train's arrival more specifically than just looking up to see where the sun was.

In the 1860s, the Great Western Railway in Britain decided to standardize time (based arbitrarily on a clock in Greenwich, because why not?) and hours became popularly subdivided into minutes and further into seconds.

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And Greenwich has been lording it over everyone ever since.

And, with the steadily increasing march of efficiency in the workplace, businesses had a way to dictate our work lives down to the second rather than staring up at the sky and making calculations on their knuckles. And this is why your life will be utterly dominated by strict adherence to those numbers until the day you die.

Hoss is the fastest runner on his street, but you can still try to follow him on Twitter.

For more history of innovation, check out 25 Seemingly Minor Inventions That Totally Changed Your Life and The 5 Most Ridiculously Unnecessary Modern Inventions.

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