Why Everyone in Japan Could Be Named Sato-san By 2531

Why Everyone in Japan Could Be Named Sato-san By 2531

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Sato as a hanko seal
Picture: 相田びさ / PIXTA(ピクスタ)
In a future Japan where couples can't choose separate surnames, 2531 could be the era of the Sato-sans, one Japanese university claims.

Ever crossed paths with a Sato? Given its prevalence in Japan, chances are you have a few in your circle Now, imagine this: by 2531, this surname might take over, multiplying until it’s the only one left.

Tohoku University’s research paints a concerning picture: a future Japan dominated by a single surname. This scenario spells trouble for diversity and the legacy of Japanese family names.

A land of Sato

The Center for Aging and Society at Tohoku University undertook a surname-focused analysis of Japan’s future amidst an aging society, declining birth rates, and marriage rates. Their study explored the trajectory and demographic trends of the most common surname, Sato.

By 2023, “Sato” stood as the top surname, with around 1,842,000 bearers nationwide, comprising 1.529% of the Japanese populace. Under the current law that dictates Japanese couples must have a single surname, Sato’s prevalence surged by 1.0083 times in just one year, from 2022 to 2023.

In light of this, the future looks alarming. According to the research, if marriage surname rules stay the same, by 2446, half the population will answer to Sato. Fast forward to 2531, a mere century later, and Sato will be everyone’s surname.

“If everyone becomes Sato-san, we might have to resort to calling people by their first names or even numbers for identification. That wouldn’t make for a particularly wonderful world, now, would it?” remarked Professor Yoshida from the Center for Aging and Society.

The estimates shift as Japanese married couples gain the freedom to decide on surname unity. Some may embrace change, while others stick to tradition. In this scenario, Sato’s dominance wouldn’t arise until 3310.

However, with the ongoing decline in birth rates, by then, only 22 Japanese people would be left. This suggests surname diversity might last until the Japanese population nears extinction. It’s not exactly reassuring, but it’s a somewhat brighter outlook.


It’s not a women’s world after all

Picture: 5x5x2 / PIXTA(ピクスタ)

The current marriage system carries a legacy of over a century, stemming from the introduction of the unified family surname in the Meiji period. The Civil Code’s inception in 1898 marked a pivotal moment, ushering Japan into a new era of civilization after years of isolation.

Yet, by contemporary standards, the marriage system was unequal. Back then, marriage ideals revolved around the husband, the household’s head, passing on his surname to his wife and family.

This rule was cemented in 1947, post-World War II, when sharing the same surname became a mandatory condition for marriage. This tradition persists today, enshrined in both the current Civil Code and Family Registration Law.

Under Article 750 of the Civil Code, “A husband and wife shall use the surname designated upon marriage.” Article 74 of the Family Registration Law stipulates that ‘A person intending to marry shall write the following items in the notification, and submit it: 1. The surname to be used by the couple; 2. Other matters specified by the Ministry of Justice.”

While the Japanese Constitution aimed for equality with “mutual consent” in marriage, it’s not quite there yet. Despite strides from the days of male dominance, Japanese marriage remains heavily lopsided. Wedding receptions still emphasize the bride joining the X family. And in family registers, the wife’s name often just tags along with the husband’s.

Concrete evidence of this imbalance comes from the country’s Gender Equality Bureau. In 2020 a whopping 95.3% of married couples went with the husband’s surname.

Why not make it two?

The debate over the “Selective Separate Surname System” has raged for a quarter-century. Advocates clamor for a new approach, one that gives married couples the freedom to choose. It’s not about abandoning unified surnames entirely; many may still prefer them. But there’s a growing anticipation for change, with many eager to hold onto their pre-marriage surnames once the opportunity arises.

Let’s explore the origins of the push for double surnames. Surnames are deeply tied to who we are, and for many, marriage can feel like a loss of that identity. And as we’ve seen, this burden falls disproportionately on women. It perpetuates the outdated notion of women being their husband’s property, merely an extension of their identity. This is why some opt not to marry or settle for common-law partnerships, even if it means giving up legal benefits. Yet providing a choice could unlock numerous benefits. It might inspire more marriages, sparking higher birth rates and other positive changes along the way.

However, efforts to revise the Civil Code have persisted since 1996, facing fierce resistance from members of the ruling Liberal Democratic Party. Their main argument? The current system mirrors traditional Japanese family values. (Never mind that the Meiji architects patterned the surname law after European law.) They also view surnames more as a public policy concern than a matter of personal freedom.

So, if surnames truly carry no social weight, why defend them so vigorously as an integral part of Japanese society?

It’s like a broken record with the LDP – whenever there’s a hint of shaking up old, outdated rules, they’re quick to cling to tradition. Take, for instance, the endless postponement of highly debated amendments like marriage equality, which a majority of the Japanese public supports. Opponents conveniently cite Japanese societal ideals and traditions to justify their stance. But as humanity marches forward, clinging blindly to tradition becomes less about preserving culture and more about stifling progress.

(Perhaps) ready for a change

But what’s the public opinion on all of this? The Cabinet Office conducts annual surveys on Selective Separate Surnames, and the latest results reveal an interesting shift. In 2012, opponents and supporters were neck and neck at around 36%. Fast forward to 2017, and support surged to 42%.

A 2023 IBJ survey gives us a peek into public sentiments about the marriage system. Turns out, over 40% of women are all in for introducing Selective Separate Surnames, but most men aren’t convinced, with 35.2% against it.

Leading the charge for change are the spirited voices of young women in their 20s. And it’s not just IBJ — Waseda University’s October survey echoes these sentiments. Over 70% of people aged 20-50 are rooting for selective separate surnames, with an impressive 80% of them in the 20 to 30 age group.

The youth are fervently rallying for this. They’re not just calling for change; they’re clamoring for it, loud and clear, and they want the government to listen.

“If separate surnames can’t be realized, I think disappointment with politics and this country will spread further among the younger generation,” said 25-year-old Ayano Sakurai, representative of the project “What is #Gender Equality?”

When old rules clash with modern progress, change isn’t just important—it’s urgent. And for a country facing a graying population, it’s a change that can’t wait. If nothing changes, Japan is in for a future where the few remaining Japanese will have to find new ways to differentiate themselves —or simply all go by Sato.

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