How Did Ancient Medics Determine the Medicinal Properties of Substances?


Drew Smith:

For the most part, they didn’t. At the dawn of the age of scientific medicine (the mid-19th century) there were only a handful of remedies that we would recognize today as safe and effective.

But why? Our ancestors were not dummies, and did not require scientific methods to create sophisticated and effective technologies. The Romans built what is still the largest unsupported dome structure in the world 1800 years ago. Gunpowder, in concert with metallurgical advances, steadily developed from a Taoist elixir to a city-destroying technology by the 1600s. Sailing technology created worldwide trade networks even earlier. Scientific methods would have sped the development of these technologies, but were not required. Trial and error—plus lots of time—sufficed.

Yet traditional medicines largely suck. Hundreds have now been tested in clinical trials. Few show any benefit at all, and even fewer show a benefit comparable to modern scientific medicines. There is little evidence that the remedies of 1800 CE were any more effective than the remedies of 1800 BCE. Moliere’s quip in 1673 that “More men die of their medicines than of their diseases” was very much on the mark.

This is a mystery, at least to me. Unlike other sophisticated modern technologies, such as jet aircraft or telecommunications, medicines are largely discovered rather than invented. They don’t rely on an entire edifice of previous scientific discoveries.

In fact, effective medicines sometimes come and find us. The ancient Nubians drank a beer (more like a gruel, really) fermented by Streptomyces bacteria. It was so loaded with tetracycline that their bones fluoresce under UV light. Tetracycline is a very effective broad spectrum antibiotic that can be used to treat plague, TB, diarrheal diseases, and respiratory, skin, and urinary tract infections. Tetracycline beer, used judiciously, could well have slashed infant mortality, leading to a Demographic Transition in Central Africa in 400 CE.

But it didn’t.

The ancients were also capable of creating, not just finding, sophisticated medicines. Bard’s Salve, resurrected from a 10th century Saxon text, is an effective remedy for wound infection in mouse models.

More surprisingly, every component—and the precise process for producing it—is required in order for it to work. This is a clear example of an effective ancient medicine that answered a critical medical need. Its formulation was written down, allowing it to spread and be improved upon. Instead it was forgotten.


I’m sure there is no single answer, but I will posit this: In a Malthusian world, effective medicines were a liability, not an asset.

Up until about 1800, everyone in the world, to a first approximation, was a poor subsistence farmer. Despite substantial technological advances, like the ones I described above and many others, the standard of living of the world’s population advanced not at all. Any improvement in agricultural technology, such as the horse collar and improved plow designs, led to increased food production but subsequent population increases ate up any gains in living standards.

We think of historical plagues as disasters, but they were in fact a great benefit—at least to the survivors. Life expectancy increased after the Black Death of 1350:

So did wages:

Fewer mouths to feed and a scarcity of labor leading to increased bargaining power led to more resources per person and a more equitable distribution of those resources.

In our modern innovation-driven economy, we consider more people to be a good thing.

We fret that declining birth rates will cause economic growth to stagnate. But prior to 1850, a growing population meant growing poverty.

Saving lives—particularly the lives of economic sinks like small children—did not make societies stronger. This is not to say that parents did not mourn the loss of their children. They did. But societies operated under what was a reverse Tragedy of the Commons, where what was bad for the individual was good for everyone else.

I think our ancestors were perfectly capable of making effective medicines. They chose not to, not out of perversity or ignorance, but because those medicines would have caused more suffering than they prevented. Medicine was not intended to cure; its role was to provide comfort. It was a form of social support, not unlike religion. Looked at from that perspective, traditional medicines are very effective. They did exactly what their creators intended them to do. I’m not sure that we can always say the same today.

This post originally appeared on Quora. Click here to view.

Presidents Day vs. President's Day vs. Presidents' Day: Which One Is It?


Happy Presidents’ Day! Or is it President’s Day? Or Presidents Day? What you call the national holiday depends on where you are, who you’re honoring, and how you think we’re celebrating.

Saying "President’s Day" implies that the day belongs to a singular president, such as George Washington or Abraham Lincoln, whose birthdays are the basis for the holiday. On the other hand, referring to it as "Presidents’ Day" means that the day belongs to all of the presidents—that it’s their day collectively. Finally, calling the day "Presidents Day"—plural with no apostrophe—would indicate that we’re honoring all POTUSes past and present (yes, even Andrew Johnson), but that no one president actually owns the day.

You would think that in the 140 years since "Washington’s Birthday" was declared a holiday in 1879, someone would have officially declared a way to spell the day. But in fact, even the White House itself hasn’t chosen a single variation for its style guide. They spelled it “President’s Day” here and “Presidents’ Day” here.

Wikimedia Commons // Public Domain

Maybe that indecision comes from the fact that Presidents Day isn’t even a federal holiday. The federal holiday is technically still called “Washington’s Birthday,” and states can choose to call it whatever they want. Some states, like Iowa, don’t officially acknowledge the day at all. And the location of the punctuation mark is a moot point when individual states choose to call it something else entirely, like “George Washington’s Birthday and Daisy Gatson Bates Day” in Arkansas, or “Birthdays of George Washington and Thomas Jefferson” in Alabama. (Alabama loves to split birthday celebrations, by the way; the third Monday in January celebrates both Martin Luther King Jr. and Robert E. Lee.)

You can look to official grammar sources to declare the right way, but even they don’t agree. The AP Stylebook prefers “Presidents Day,” while Chicago Style uses “Presidents’ Day.”

The bottom line: There’s no rhyme or reason to any of it. Go with what feels right. And even then, if you’re in one of those states that has chosen to spell it “President’s Day”—Washington, for example—and you use one of the grammar book stylings instead, you’re still technically wrong.

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Full vs. Queen Mattress: What's the Difference?

If you’re in the market for a new mattress this Presidents Day weekend (the holiday is traditionally a big one for mattress retailers), one of the first decisions you’ll need to make is regarding size. Most people know a king mattress offers the most real estate, but the difference between a full-sized mattress and a queen-sized one provokes more curiosity. Is it strictly a matter of width, or are depth and length factors? Is there a recommended amount of space for each slumbering occupant?

Fortunately, mattress manufacturers have made things easier by adhering to a common set of dimensions, which are sized as follows:

Crib: 27 inches wide by 52 inches long

Twin: 38 inches wide by 75 inches long

Full: 53 inches wide by 75 inches long

Queen: 60 inches wide by 80 inches long

King: 76 inches wide by 80 inches long

Depth can vary across styles. And while you can find some outliers—there’s a twin XL, which adds 5 inches to the length of a standard twin, or a California king, which subtracts 4 inches from the width and adds it to the length—the four adult sizes listed above are typically the most common, with the queen being the most popular. It's 7 inches wider than a full (sometimes called a “double”) mattress and 5 inches longer.

In the 1940s, consumers didn’t have as many options. Most people bought either a twin or full mattress. But in the 1950s, a post-war economy boost and a growing average height for Americans contributed to an increasing demand for larger bedding.

Still, outsized beds were a novelty and took some time to fully catch on. Today, bigger is usually better. If your bed is intended for a co-sleeping arrangement with a partner, chances are you’ll be looking at a queen. A full mattress leaves each occupant only 26.5 inches of width, which is actually slightly narrower than a crib mattress intended for babies and toddlers. A queen offers 30 inches, which is more generous but still well below the space provided by a person sleeping alone in a twin or full. For maximum couple comfort, you might want to consider a king, which is essentially like two twin beds being pushed together.

Your preference could be limited by the size of your bedroom—you might not be able to fit a nightstand on each side of a wider bed, for example—and whether you’ll have an issue getting a larger mattress up stairs and/or around tricky corners. Your purchase will also come down to a laundry list of options like material and firmness, but knowing which size you want helps narrow down your choices.

One lingering mystery remains: Why do we tend to shop for mattresses on Presidents Day weekend? One reason could be time. The three-day weekend is one of the first extended breaks since the December holidays, giving people an opportunity to trial different mattress types and deliberate with a partner. Shopping Saturday and Sunday allows people to sleep on it before making a decision.

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