The title for this week's episode, ""They all exchange hellos and goodbyes at the famous gates of Afusaka," comes from poem #10. Here is the University of Virginia translation:
Truly, this is where
Travelers who go or come
Over parting ways--
Friends or strangers--all must meet:
The gate of "Meeting Hill."
Mostow:
This it is! That
going, too, and coming, too,
continually separating,
those known and those unknown,
meet at the barrier of Ōsaka.
The key to understanding why the animators chose the poem for their title is to pin down the location of the "famous gates of Afusaka," or as Mostow puts it, "the barrier of Ōsaka." It is not the modern city of Osaka, which, in Heian times, was called Naniwa. Rather, "the barrier of Ōsaka" refers to a place along the road close to the eastern entrance into the old capital of Kyoto. As the
Japan Navigator site explains, "The Ausaka Barrier ("Meeting Slope", also pronounced "Osaka" but not connected with the city of that name) forms the border between Yamashiro and the old capital Heiankyo (now Kyoto) and the province of Omi (now Shiga Prefecture) where the road to eastern Japan starts." This Omi is the same Omi as we know in Omi Jingu, Omi Shrine, the Shrine at Omi.
The poem is set in the same location--or as close to it, as any of the 100 poems can refer--that Chihaya and her friends find themselves at the close of the episode, as they prepare for the high school National karuta competitions. And the poem's topical description of travelers meeting each other on the road precisely describes--or anticipates, really--the reunions that will shortly take place between Chihaya and Arata and Shinobu on the tatami. The title poem is a perfect choice to accentuate the meetings of friends and rivals that will take place as everyone converges at Omi Jingu for the karuta competitions.
For those interested, I urge you to follow the link to the Japan Navigator site, as the writer there discusses in more detail not only the semi-mythical author of the poem, Semimaru, but also the traditional Buddhist understanding of the waka, which recognizes in the momentary intersections of friends and strangers on the road a symbol of the general transitory nature of life.
I would add only one further point. We ordinarily take friends and strangers, those known and those unknown, as different people. But we don't have to: they can be the same people, as we discover unknown things about people we thought we knew. That is much more a theme of this episode, as we discover Chihaya's mother's apparent neglect of Chihaya belies a basic trust in Chihaya herself and in karuta, or that Chitose--who disdains Chihaya and karuta--in fact relies on Chihaya's dedication as an inspiration to pursue her own dream. Chihaya discovers that Arata is more of a stranger than she knew, when she learns he has no interest in team competition. And perhaps, in response to Sumire's blunt questioning, Chihaya becomes something of a stranger to the naive person she herself has been until now.
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Spoiler for Manga observations.:
It is interesting to go back and reread the earliest issues of the manga. You can see there the basic theses of Chihayafuru being set out. For example, Harada makes the comment to one of his nurses that the children cannot continue in karuta unless they have friends who will support them ("they can't continue playing it without friends.") Of course, the current anime episode is a perfect illustration of that point, as Chihaya's mom's support is decisive to maintaining Chihaya's dedication to karuta. Suetsugu is marvelously consistent in her conception of the core themes of the series.
Kirarakim is absolutely correct to point to friendship as being central to this story. I don't think there is a more basic theme--it trumps even karuta. Romance is poor cousins.
I did learn one thing while rereading. I have thought of Chihaya as sexually immature, simply unaware of boys. This turns out not to be the case. She tells her friend in the seventh issue that she joined the track and field club in order to meet boys, that for her the club was like "an online dating site." (!!!) As she puts it, "like everyone else, I just wanted a friend," ie a boyfriend. So Chihaya knows about boys. She's not sexually immature. Instead, Chihaya has bracketed off sexuality, in order to pursue her dream of playing karuta, and reviving the friendships she remembers with Taichi and Arata.