The Gregorian system is the internationally accepted calendar system. Japan officially adopted a variant of the Gregorian in 1873. Before the adoption, Japan primarily used a seven day calendar system lunisolar system for roughly 1200 years. Some of the elements of the system carried over to the Gregorian.
Have you ever given thought about the names given to the days of the week? The naming scheme comes from the combination of the Chinese philosophies of yin-yang and the five Taoist elements.
Very algebraic, eh? Now you can go around and impress your peers with this newfound knowledge.
But wait! Did you know that alongside the seven-day calendar systems used in the last 1400 years, there was another system used by the Japanese (and other parts of Asia)?
This secondary calendar system has a profound impact in many Japanese lives. If you have seen an Asian calendar, you may have noticed kanji under the numerals. These are the names of the days under the six-day calendar system known as the Rokuyō (六曜, literal translation roku = six and yo = weekday. The kanji combination makes sense!).
So, what is the the Rokuyō and how does it impact Japanese lives?
Want to learn about Rokuyo? Today is your lucky day!
The Rokuyō is a variation of the original that came from China around the 14th century. As mentioned earlier, Rokuyō comprised six cycling days that are based on astrology. Each day determines the level of auspiciousness. In other words, it’s a fortune telling calendar system. Oh, Japanese, you are so superstitious (If you haven’t yet, check out the superstition article I wrote a while back!).
The following are the six Rokuyō days in cycling order.
|先勝||Good luck in the morning. Bad luck in the afternoon.|
|Tomobiki||友引||Good luck all day except noon.|
|先負||Bad luck in the morning. Good luck in the afternoon.|
|Butsumetsu||仏滅||Represents the day Buddha died. Bad luck for the entire day. Wouldn’t poke at it with a stick.|
|Taian||大安||Good luck for the entire day. The most desirable day.|
|赤口||Bad luck all day except at noon.|
These days cycle in order through each Gregorian month. For example, January 1st starts out as Senshō, January 2nd is Tomobiki, January 3rd is Senbu, and etcetera.
One variation of the Rokuyō has the first day of each month starting on a certain day depending on the month. January 1 starts out as Senshō, February 1 starts out as Tomobiki. March 1 starts out as Senbu. Are you starting to see the pattern? On the 7th month, the first day resets back to Senshō. Another version has Senshō starting on January 1st and cycle through the six days until a new year begins.
How serious do some of the Japanese take into account the Rokuyō in their daily lives? Although the newer generation seem indifferent about it, the more mature group take the system into heavy consideration.
For example, about three times as many weddings are held on Taian than on Butsumetsu. Due to this huge difference in planning, rates for weddings held on Butsumetsu days are discounted heavily. Many major events other than weddings favor Taian over Butsumetsu.
Child birth on a Taian day is highly desirable. With the advances in modern medicine, many parents opt to induce labor if a desirable day is near or to delay the birth if the day falls under Butsumetsu. I’ll let you decide if this is a healthy, sane decision. I couldn’t find numbers relating to the Japanese, but in 2003 a study done in Taiwan saw a significant increased in scheduled births on auspicious days versus non-auspicious days1.
Just from glancing at the list, one would deduce that you wouldn’t want to plan anything important on Butsumetsu. That’s not always the case.
The kanji for Tomobiki literally translates to “pulling a friend.” Due to it’s name, it is considered bad luck to schedule any funerals on these days. What kind of dead friend would pull you to the death realm, anyway? Crematoriums are typically closed on this day. Good to know.
Also another good thing to know: some Shinto shrines close on Butsumetsu. If you ever plan on visiting one, be sure they are open on the day you are visiting!
Before the next time you decide to munch on some of that delicious mochi or perhaps a quick bite of eel and watermelon (great pairing of food items, I’m told), take a quick glance at this version of the Rokuyō calendar to make sure the day and time of day is aligned in your favor. According to this, yesterday was 4-4 and butsumetsu. How bad was your day, yesterday?
Why should you check this, though? Because Tofugu cares about each and every one of you!
 “Patients’ attitudes vs. physicians’ determination: implications for cesarean sections.” Soc Sci Med. 2003 Jul;57(1):91-6.