Short Wave - The Shared History Of The Chinese And Gregorian Calendars

Episode Date: February 12, 2024

Happy Lunar New Year! According to the Chinese lunisolar calendar, the new year began Saturday. For many, like our host Regina G. Barber, this calendar and its cultural holidays can feel completely detached from the Gregorian calendar. Growing up, she associated the former with the Spring Festival and getting money in red envelopes from relatives, and the other with more American traditions. But the Chinese calendar has a deep, centuries-long shared history with the Gregorian calendar. To learn more about this shared history, Gina talks to scientists and historians, who spill the tea about the science behind calendars, and how both calendars and the Chinese Lunar New Year celebration played a key role in the rise and fall of empires. Email us [e-mail] for more science history. See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

You're listening to Shortwave from NPR. In September 1752, England lost 11 days in an instant. And people were furious. They really wanted their 11 days back. Space historian Osnot Katz Moon says that's because throughout history. What kind of calendar you keep has actually been quite controversial because historically, calendars have been tied to senses of identity. England lost these 11.

days because roughly 1,800 years earlier, when astronomers were creating the Julian calendar, they overcompensated for one crucial detail, the length of a year. Osnott says that astronomers had known for a long time that the year lasted about 365 and a quarter days. And when creating the Julian calendar, astronomers overcompensated by adding an extra day in February every four years. It turns out, this blunt estimate of a quarter, it was 11 minutes too long. Earth's orbit is around 11 minutes shy of a quarter of a day. So after many centuries of using the calendar, it had become 11 days off of the Gregorian calendar that much of the rest of Europe had switched to nearly two centuries earlier. The Gregorian calendar is the one used by

much of the world today. It tracks time using the position of the sun in the sky. But there are many kinds of calendars used to track time around the world. Either they track the position of for the sun in the sky. So that's a solar calendar, or they track the phases of the moon, and that's a lunar calendar. Or sometimes you get what's called a loony solar calendar, which is where you're tracking the months by the phases of the moon, but you're tracking the year by the position of the sun in the sky. Jonomar Juvenanti Singh, a science historian at the University of Cambridge, says the Chinese lunar calendar is a an example of this. The Chinese calendar, for example, is often described as a lunar calendar because it's based on observations of the sun, the moon, and the five planets that were

recognized in historical Chinese astronomy, so Mercury, Venus, Mars, Jupiter, and Saturn. Because of the differences in the Chinese and the Gregorian calendars, we have both the New Year that starts on January 1st every year and the Lunar New Year that began Saturday. This new year is the most important holiday in many parts of Asia, especially China. And what's surprising to me is that two things I thought were so different, the Gregorian calendar that I use for my birthday, and the Chinese calendar that mandates when I get those red envelopes filled with money from relatives, among other things, those two calendars have a shared history,

thanks to German and Italian Jesuit missionaries from the Catholic Church. It was the Jesuits who played a crucial role in reforming the Julian calendar to the Gregorian calendar. Europe, and then going to China, their fellow missionaries were amongst those who were reforming the Chinese calendar during the Lake Ming dynasty. Today on the show, why calendars can be pivotal to the rise and fall of empires. We look at how tracking time can prevent famine and unrest and how the Chinese New Year celebration played a key role in all of it.

I'm Regina Barber. You're listening to Shortwave, the science podcast from NPR. To understand how something as mundane as a calendar can influence governments, we first have to zoom out to the big picture of what calendars do. The purpose of a calendar is mostly for planning ahead. There's no reason to name the days and the months and to divide a year into segments unless you're trying to plan for future events. Which Emily Lockdwalla, author and planetary scientists,

says includes everything from cultural festivals to agriculture, feeding an entire society. A calendar can give you. a more scientific approach to agriculture because you might observe how many days or weeks or months it takes for the life cycle of an important crop to come to fruition. So from planting, how long it takes for germination, how long it takes for something to mature, and then how long you have to harvest it before it gets bad. And second of all, it helps you know when the right time is to plant, how you can predict seasonal events like rainy weather or enough sun for a crop to mature.

And a calendar lets you mark those times as they repeat throughout the year and predict when they're going to happen in the future. It's really all about telling the future. Solar and loony solar calendars do that by tracking the sun. The position of the sun in the sky is dictated by the tilt of the earth and where the earth is in its orbit. This is what creates the seasons. And Jan Amar says that these astronomical observations, especially in China, they are central to harvests. In Beijing, there is the Imperial Astronomical Bureau, which is filled with astronomers who are constantly observing the sky,

designing a calendar that then gets issued every year. He also says that marking time is not only scientific, but political. In the mid-1600s, Jesuit missionary Martino Martini, went to China as part of a decades-long interest from the Catholic Church in better understanding biblical history. Like pinning down when the Great Flood that wiped out and restarted humanity happened, you know the one with Noah's Ark. And he knew that the Chinese kept meticulous historical records. When the Jesuits got to China, something that really struck them was that Chinese astronomical records

seemed to stretch back to before the date of the flood. So there's this sudden moment of crisis. You know, what do they do when it seems that China is older than the flood? If the flood wiped out all records of earlier civilizations, how is it possible that something from China goes back earlier? But even with these meticulous records, China is undergoing its own political crisis. Many parts of China had experienced drought and were suffering from famine. The Ming Dynasty is on the verge of collapse,

fighting a civil war against a peasant revolt and the Manchu army. That was an astronomical crisis. or a calendar crisis as well, because when one dynasty was ending, that meant that the mandate of heaven was up for grabs, essentially. It's in this context where astronomy becomes absolutely crucial to political victories. It's at this vulnerable time that the Jesuit missionary Adam Chalvan Bell presents a version of the Gregorian calendar to the Ming Emperor, who quickly adopts it in his final year as ruler. And it was quite rapidly appropriated by China. So China essentially shifted to a Gregorian calendar,

but it maintained its own festivals and its own sort of cultural importance attached to predicting eclipses, for example. And once the Qing Dynasty that's made up of Manchu leaders takes power, they're eager to continue using it, because the Gregorian calendar lets them more accurately predict solar eclipses, which reinforces their supposed divine mandate of heaven to rule. The Jesuits also pick up information from Chinese leaders about their agricultural practices that only get better as experimentation with growing crops in the north comes to fruition

and the Qing Dynasty is able to feed its population. And with time, the government becomes seen as an agricultural leader. Flash forwards 110 years roughly and Europe is being devastated by the Seven Years' War, which has fought mostly in agricultural fields and in it. it leads to several grain crises, many famines. Which means there's internal social unrest that individual European leaders must quell in addition to their external battles during the seven years' war. And it's in that context that a group of French reformists, the physiocrats,

start pointing to China as a model to rebuild Europe's agriculture. And to understand China's agriculture, they say you need to understand the Chinese calendar and Chinese astronomy. And Europeans perceive China at this moment to be the greatest empire in all the world. And in fact, much of the world's wealth is produced in China in this period. So it's very stable and Europe instead is ravaged by one of its most devastating wars. And in fact, the seven years war has been described in some ways as the first actual world war. So many European rulers look to China for guidance.

But instead of taking the precise agricultural science that could be pulled from the Chinese calendar, European leaders pull Chinese cultural practices that reinforced the ruler's supposed divine mandate to rule. So the European leaders become particularly interested in one very unique Chinese ceremony that would always take place on the date of the spring festival. That's Chinese New Year. So as the Jesuits had written and published in Europe, every spring festival, the emperor of China, would proceed from the forbidden city to the Temple of Heaven, and would plough the fields himself.

You know, to see the Son of Heaven himself physically ploughing the field must have been striking, particularly for these missionaries who, they're also used to these discourses of the kings in Europe being divinely appointed or having a divine right. And in the 1700s, European advisors, such as Francois-Cené, suggested that after the devastation of the Seven Years' War, the French royals and the Habsburg royals should replicate a similar ceremony.

They hoped that copying this field plowing would improve agriculture and in turn strengthen their authority. So the French crown prince got into the soil and started plowing it. And there's an explicit recognition that this is a replication of a Chinese ceremony. There are published accounts from the time that says, say the ceremony doesn't only consist in plowing the earth so that the king can stir up emulation by his great example, but it's a sacrifice that the emperor makes to heaven. So this is quite literally borrowing a Chinese astronomical concept and translating it into European politics.

So what happens after? They mimic Chinese traditions. Does it help their agriculture? It doesn't. It doesn't satisfy the grain crime. that are ravaging France at this period of time. The English start getting very suspicious of all these Catholic countries replicating Chinese ceremonies, and there's this immediate association between all things Catholic with all things Chinese that starts to emerge after the French king and the Holy Roman Emperor do these ceremonies,

but it really doesn't turn out to be very good for them. To me, it's pretty striking that across these hundreds of years, the calendar was the central problem-solving tool used across these empires. Because as a kid, growing up in a small town in Washington State, I felt like nobody knew about Chinese New Year, which was so important to me and my family. But hundreds of years before, the Chinese calendar, with all of its important cultural practices,

was a huge vehicle for information. Even though, I honestly take these calendars for granted most of the time. This episode was produced by Rachel Carlson, edited by our showrunner Rebecca Ramirez and fact-checked by Britt Hansen. Gilly Moon was the audio engineer. I'm Regina Barber. Thanks as always for listening to Shorewave from NPR. Xing Nguila.