Japan

I visited the Ochanomizu Origami Kaikan (お茶の水おりがみ会館) as a fun little diversion in Tōkyō. The centre is part shop, part school, and part studio. I got to take some photos of the paper-dying process and took home some supplies that might inspire me to make some more origami soon!

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Origami paper can be dyed, painted, or both depending on the intended pattern. When I visited, the artisan was using a special multi-headed brush to paint green stripes on one side of the paper; the other side had already been painted gold using a very wide, soft brush to achieve a consistent finish. The result is a pattern perfect for folding into snake decorations for the upcoming new year!

As you might have guessed from an earlier post, I have acquired a minor obsession with the colours of fire hydrants. You can bet I had my eyes peeled in Japan to see how hydrants look there — and the answer was fascinating!

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The first things I noticed in Tōkyō were the round red signs everywhere indicating the presence of a fire hydrant (消火栓)… and a distinct lack of fire hydrants.

It turns out that hydrants in Japan are generally installed underground except in particularly snow-prone areas. The signs point to the plate on the road or sidewalk that covers the hydrant cap.

Many parks and private property also have fire cisterns (防火水槽) and other water conservancies (消防水利) that store water to fight fires after a major earthquake, when the main water network may be damaged.

Hoses, pumps, and other fire suppression equipment are scattered throughout the city so that trained residents and disaster volunteers can use them to suppress fires during a major disaster.1

Footnotes

Credit card terminals in Japan are pretty similar to those in Canada — you can use tap (タッチ) or insert your card and enter your PIN to authorize the transaction. But there’s one twist that confused me at first. If you need to enter your PIN on a touchscreen, the numbers on the number pad are displayed in a random order!

I have no idea if this is unique to Japan or if it’s just new to me, but it does seem like a helpful security feature to ensure that your PIN can’t be guessed later based on the fingerprint smudges on the screen.

When I stopped by the Nintendo store in Kyōto, I knew I needed to get an product with the company’s oldest mascot on it. No, I don’t mean Mario, Link, Donkey Kong, or even Mr. Game and Watch. I’m talking about… Napoleon Bonaparte?

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If you weren’t aware, the Nintendo corporation is much older than video games. It was originally founded in 1889 (Meiji 22) to produce hanafuda cards (花札) — which it still makes today!

A hanafuda deck consists of twelve suits of four cards each, all with abstract designs (originally to evade Edo-era anti-gambling laws). The cards are much thicker than western playing cards (トランプ) but are about a third of the size.

As shown above, Nintendo’s hanafuda come in a box with Napoleon’s portrait on it. That has been the case since at least 1901 (Meiji 34), although the company once had many other brands of cards featuring other historical figures like Saigō Takamori (西鄕 隆盛) and fanciful designs like tengu (天狗).

It’s not clear why Napoleon was chosen, why he got top billing, or why he remains the face of hanafuda today. One theory suggests it was copied or acquired from an American brand, which in turn may have been named after an English card game, but this is purely conjecture.

Footnotes

While in Japan, I dabbled in the perfect hobby for obsessive-compulsive travellers like myself: stamp collecting!

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All over the country, train stations have distinctive rubber stamps (駅スタンプ) for travellers to mark their stampbooks with to commemorate their journey. These really took off in the 1970s1 when Japanese National Railways installed stamps at 1400 stations as part of its DISCOVER JAPAN campaign.

Prior to then, stamps were already offered at a handful of individual stations; enthusiasts had been collecting commemorative postmarks since the late Meiji era (1900s-1910s). An even earlier tradition had temples and shrines award stamps called goshuin (御朱印) as a proof of pilgrimage for their devotees.

With that said, here are the stamps I collected on our recent trip!

JR West stamps

I collected four classic stamps from JR West’s stations in Kanazawa and Kyōto.

JR East stamps

I absolutely love JR East’s refreshed 2020 stamp designs for its Tōkyō stations. Each incorporates one character of the station’s name with some distinctive feature of the surrounding neighbourhood. I collected six stamps from the Yamanote line (山手線) and one from the Chūō line (中央本線).

Tourist stamps (記念スタンプ)

Train stations aren’t the only places you can get stamps. Tourist information centres at major destinations often have their own stamps for visitors, and even some stores participate in limited-time stamp rallies.

Goshuin

Stamp collecting in Japan is at least informed by, if not directly descended from, the practice of receiving goshuin (御朱印) on a pilgrimage to a temple or shrine. Conversely, goshuin were influenced by the success of stamp collecting: many sects offer them to collectors and other travellers for a small donation, regardless of faith.

I had one goshuin entered into my stampbook at Honnōji (本能寺) in Kyōto.

Footnotes

Leah and I are back from a three-week trip to Japan! It was my first trip to the country, and only my second time away from North America. Over the next few months, you can expect plenty of posts with photos, observations, and souvenirs from the trip.

For now, here’s an overview of our itinerary and some initial thoughts of how it went.

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Tōkyō (東京)

We started the trip with four full days in Tōkyō. I was worried I’d be totally overwhelmed, but I was pleasantly surprised by how manageable it was. Part of that was location: our hotel in the centrally-located but less hectic neighbourhood around Ōtemachi (大手町) and Kanda (神田) provided a home base for us to retreat to.

But even the busiest areas of Shibuya (渋谷), Ginza (銀座), and Ikebukuro (池袋) were not as bad as I expected. It turns out that thousands of pedestrians and tens of vehicles is not much more of a sensory overload than an urban experience with hundreds of each.

We mostly stuck to the central core of Tōkyō within the Yamanote Line (JY 山手線) and took advantage of our central location on several metro lines:

• Marunouchi (Ⓜ 丸ノ内線)
• Ginza (Ⓖ 銀座線)
• Hanzōmon (Ⓩ 半蔵門線)
• Chiyoda (Ⓒ 千代田線)
• Tōzai (Ⓣ 東西線)

I’m very glad I studied the geography and metro lines of Tōkyō before I left!

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Kanazawa (金沢)

After we had our fill of Tōkyō, we took the Hokuriku Shinkansen (北陸新幹線) to Kanazawa, the capital of Ishikawa Prefecture (石川県) on the coast of the Sea of Japan. The city is home to roughly half a million people and many traditional arts and crafts dating from the Edo era.

In our three days in Kanazawa, we stayed in the historic Higashiyama (東山) teahouse district and took a bunch of craft workshops I’ll cover in future posts.

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Kyōto (京都)

The final leg of our trip was five days in Kyōto. The cultural capital is home to lots of historic landmarks and is ground zero for Japan’s challenges for overtourism. Our itinerary was focused more on Kyōto’s traditional crafts than the major tourist destinations, and it became even more so as we adjusted our plans to account for travel fatigue.

With hindsight, it would have been better to plan a slightly shorter trip and stay somewhere on the Karasuma subway line (烏丸線) rather than the tourist-heavy Gion district (祇園), but we still had a very nice time.

The highlight of Kyōto for me was definitely the railway museum — more on that in a future post.

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Food

It is cliché to talk about all the amazing food one eats on a trip, but this has historically been challenging for me since I have a bit of a fragile stomach.1 Fortunately, Japan is full of food that is tasty and easy on the stomach, so our trip was both gastronomically and gastrointestinally satisfying!

Our favourite go-to meals were cold soba (そば) for Leah and unajū (鰻重) for me, although we also had excellent yakitori (焼き鳥), okonomiyaki (お好み焼き), oyakodon (親子丼), shrimp omurice (オムライス), and grilled salmon teishoku (鮭定食).2 I definitely missed my daily serving of peanut butter, but Japan’s famously incredible convenience stores (コンビニ) made up for it by providing snacks and reasonable emergency meals.

Language

It’s been a hot minute since I studied Japanese in university, but I was very thankful for my basic vocabulary and ability to read hiragana, katakana, and a handful of kanji. I’m sure it’s possible to visit Japan without knowing any of the language — million of tourists do it every month — but language was so core to our experience that I have a hard time imagining it.

Multilingual signage can be found everywhere at major attractions, in many restaurants, and on public transportation.3 But it’s a lot more efficient to be able to read and listen for directions in multiple languages, especially in smaller places where the English versions might be slightly dubious.4

I was surprised at how much value I got just from having a working knowledge of katakana. Japanese has a lot of English loanwords, to the point that you can navigate many stores just by sounding things out. At a drugstore, you might see my lips move as I read スキンクリーム as su-ki-n-ku-ri-i-mu — oh, this is skin cream!

People were universally very complimentary of our Japanese skills — not because we were any good, necessarily, but because we were showing consideration by putting in the effort. And they were more than willing to meet us halfway by simplifying their own speech, dropping in English words they knew, and being patient with us. There were a few very special interactions and experiences we were able to have in Japanese, and I’m very grateful to everyone we met for accommodating us.

Back home

We had a wonderful trip, but it’s great to be back home in our own bed with our cat and our routine. I’m sure we’ll be back one day, although it might take a few years to work up the energy for another trip of that length. Until then, I hope you’ll excuse me using this website to look back on my experiences for the next little while!

Footnotes

One of the most recognizable features of Japanese architecture is the matted flooring. The individual mats, called tatami, are made from rice straw and have a standard size and $1 \times 2$ rectangular shape. Tatami flooring has been widespread in Japan since the 17th and 18th centuries, but it took three hundred years before mathematicians got their hands on it.

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According to the traditional rules for arranging tatami, grid patterns called bushūgishiki (不祝儀敷き) are used only for funerals.1 In all other situations, tatami mats are arranged in shūgishiki (祝儀敷き), where no four mats meet at the same point. In other words, the junctions between mats are allowed to form ┬, ┤, ┴, and ├ shapes but not ┼ shapes.

Shūgishiki tatami arrangements were first considered as combinatorial objects by Kotani in 2001 and gained some attention after Knuth including them in The Art of Computer Programming.

Construction

Once you lay down the first couple tatami, you’ll find there aren’t many ways to extend them to a shūgishiki. For example, two side-by-side tatami force the position of all of the surrounding mats until you hit a wall.

This observation can be used to decompose rectangular shūgishiki into

• $(m-2)\times m$ blocks forced by vertical tatami,
• $m \times m$ blocks forced by horizontal tatami, and
• $1\times m$ strips of vertical tiles,

and to derive their generating function

$$T(x) = \frac{(1+x)(1+x^{m-2}+x^m)}{1-x^{m-1}-x^{m+1}}$$

Four-and-a-half tatami rooms can also be found in Japanese homes and tea houses, so naturally mathematicians have also looked into tatami tilings with half-tatami. Alejandro Erickson’s PhD thesis reviews and extends the research into this area. Alejandro has also published a book of puzzles about tatami layouts.

Footnotes