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25 Nov 21

Kai-awase: the shell-matching game

The origins of Kai-awase

Kai-awase (貝合わせ), the game of ‘matching shells’, is included among a number of aristocratic pastimes belonging to the category monoawase (物合わせ), a ‘competitive comparison among things’ that was popular in the eleventh and twelfth–century Japanese court. The subjects to be compared and judged ranged from man-made creations like poems, paintings and musical instruments, to natural phenomena like flowers, roots of the calamus plant, birds, insects and miniature tray gardens. The examples of clamshells and incense (which will be discussed in this essay) differ from the general format of mono-awase pastimes, but share the basic element of competition, so I will lay out the general rules here.

A mono-awase competition was divided into two teams, called the Left and the Right. The teams were usually composed of high-ranking related family members or affiliated persons. In the case of a poetry competition (uta-awase 歌合わせ), arguably the most serious type of match, a lower-ranked person of exceptional poetic skills might be asked to join a team. The fact that compositions could potentially end up in imperial anthologies raised the stakes for inclusion of a poet of real talent. There were team colours – warm (purples and orange) for the Left, and cool (lavender-blue and yellow) for the Right. Young girls dressed in the team colours were drafted as assistants, and accompanying accoutrements were coordinated to match. Each side would present a pair of corresponding objects, whatever the category might be, to the umpire, usually a courtier of high cultural recognition, who would decide which of the pair was superior. Pair after pair, the results were recorded by each team’s official scorekeeper.

In modern Japan, a contest consciously based on this historical model is alive and well in the annual televised event, the Red & White Year-End Song Festival (Kōhaku Uta Gassen 紅白歌合戦), which has been avidly watched in Japan since 1951. The other courtly games of competition – paintings, flowers, insects and the like – all died out long ago, with the exception of shells and incense. These two continued to flourish, picking up new cultural symbolism and meaning along the way.

The reason the ‘shell-matching’ game does not fit the standard format of mono-awase described above has to do with the different nuances of the word awase. The verb awaseru (合わせる) contains the sense of ‘oppose’, but also ‘compare’ and ‘join’. For most of the monoawase pastimes, it is the connotation of facing off that comes into play. In the case of the shells, however, the basic tenet of the game, and the resulting symbolism that carried on historically, comes from the other sense of awase, ‘to join’. The two sides of a bivalve shell click into one another in a perfect fit – and only do so with their natural other half – a subtle but unmistakable fact not visible to the eye but confirmed by touch. The players in a game of kai-awase may be competing, but the shells themselves are not. The object of the game of kai-awase, in whatever form it may take, is to make pairs.

Playing the game

From the start, shell matching was most popular among women and girls. This is another aspect of the game that makes it different from all the other mono-awase pastimes, which were not limited to one gender. The shells used were clams, ideally from Ise Bay in central Japan, of a size to fit nicely in a girl’s hand. They were cleaned and polished then the interiors covered in paper and gold leaf and decorated with scenes from nature, or often from The Tale of Genji, a classic work of Japanese literature from the beginning of the eleventh century written by noblewoman Murasaki Shikibu. The same picture was painted on both halves of the shell on the inside. The outsides of the shells were polished but undecorated. Unlike the other mono-awase contests, which were judged on straightforward aesthetic terms, there was a deeper metaphysical meaning encoded in the shell game. The half shells were separated into two groups, symbolising heaven and earth. The right-hand half, the yin side, represented earth and were called the ‘shells to be played’ (dashigai 出貝); the left-hand side, yang, stood for heaven and were called the ‘fixed-in-place’ shells ( jigai 地貝). The two matching half shells would be separated into two octagonal lacquered boxes (oke 桶; literally ‘tub’) with woven silk cords. In its most elaborate form, this version of the game consisted of 360 matched clamshells, a number that mirrored the average number of days in a year according to the astronomical almanac. Like the other, more established mono-awase pastimes, the game was very social and usually played by twenty players or so.

Setting up the game

The yang jigai were arranged, face down, in the following manner. Twelve of these half shells, symbolising the twelve months, were set in a circle, along with seven more representing the days of the week. The resulting number, nineteen, represented the Metonic cycle, in which the moon returns, in the same phase, to the same longitude in the sky. The remaining shells were arranged in nine more or less equal lines, representing the nine layers of heaven. Thus placed, the game was ready to be played. The first player would take a yin dashigai from the other container and place it in the centre, face down. The remaining players, sitting in a circle around the shells, would then take turns trying to match this shell with its jigai mate. They did so by looking at the natural, outside surface of the face-down shells, which all sported similar subtle narrow stripes and natural patterns of beige and brown.

Taking one’s turn, the player picked up the dashigai from the centre in her hand, still face down, covering it with her kimono sleeve. After choosing a jigai, she picked it up – without looking at the underside – and slid it on top of the dashigai in her hand. If the halves did not click perfectly together, she simply returned the jigai to its place. If it were a mate, however, it clicked into place and she knew, without looking, that she had a match. At this point she would take the two halves out and hold them up to show the painted interiors to the other players. They could see at a glance that the pictures matched. No cheating possible here! She might be permitted to choose another dashigai from the container and try again or simply hold her pair while play moved on to the next person. This manner of playing is why the game was also called ‘shell-covering’ (kai-ooi 貝覆い). The winner was she who, at the end, had collected the most paired shells.

Historical changes in kai-awase

By its very nature, the concept of matching shells lent itself to various changes and simplifications. One version was to paint the shells with two parts of a famous poem, with the goal to unite the poem, or even have one side be a portrait of the poet, the other the poem they composed. This concept was later taken by cards (karuta), most famously the Hyakunin Isshū anthology of 100 poems by 100 famous poets. The card version of this game soon superseded the shells and is still played today. It is a traditional New Year’s pastime. Another simplified version, which likely used fewer shells, was to simply turn all the shell halves face down then take turns flipping them over, two at a time, to find a match. If there was no match, the shells were put back in place and the next player took a turn. The better a person could remember where particular pictures were located, the more successful they would be in finding pairs. Whoever ended up with the most matched pairs was the winner; it is the same principle as our card game Concentration, or Memory. This version could also be made more sophisticated by requiring the player who makes a pair to compose a poem on the subject depicted on the shells.

The objects put forth for comparison in most mono-awase competitions (with the possible exception of poems, which might be preserved in anthologies) were ephemeral. Two branches of flowering plum offered for consideration; two paintings evaluated for the emotions they evoked; two rhizomes of calamus sporting long filaments of rootlets; two painted fans. These things were the focus of intense appreciation for the moment, but were probably cast aside when the competition was over. The sumptuously gilded and painted clamshells, however, were a different matter. They were painstakingly crafted and valued objets d’art in themselves. The always-paired containers used to store the two halves of the shells were examples of fine lacquer, often with elaborate relief decoration, and were also highly valued. These kai-oke (貝桶; ‘shell tubs’) became precious objects, heirlooms and eventually an essential item in an aristocratic bride’s trousseau. By the Muromachi period (1338–1573), even as the courtly world of the nobility was overshadowed by the military world of the shoguns, the fashions of the aristocrats often seeped into the culture of the samurai class. For example, the custom of endowing a bride-to-be with a set of shells was taken on by the samurai class, but the decorative octagonal lacquer boxes might instead feature simple yet elegant family crests. The sets of shells had a prominent place in the ceremonial procession from a bride’s family home to that of her new husband. The chief retainer of the bride’s father oversaw the transportation of the boxes and presented them to the groom’s family in a ceremony known as the ‘presenting of the shell boxes’ (kai-oke watashi 貝桶渡し).

Women and clamshells

Is it an accident that clams became so closely associated with women? It hardly needs mentioning that female genitalia is often compared with clams. In other ways, too, clams and their shells whispered to women alone. Too often, failing to match the shells was thought to hint at a possible moral failure. In this way, for the girls who played, the shells were perhaps more than just a game. ‘A virtuous woman does not give herself twice’ was one of the moral injunctions for women of the samurai class. In other words, like the half shells, which have one match and one only, a woman should cleave to her husband, even when widowed. The shells were the perfect symbolic embodiment of this injunction. During the Edo period, the elaborate boxes of shells may have been de rigueur dowry items for the wealthy, but their symbolism was too valuable to limit to the upper classes. The third day of the third lunar month has long been celebrated as Girls’ Day, or ‘the Doll Festival’ (hina matsuri 雛祭). Miniature replicas of the shell boxes became standard items in the set of imperial dolls and courtiers set out in a tiered arrangement in a girl’s home. They are still seen as essential parts of these displays. More recently, some modern wedding ceremonies have incorporated an exchange of painted half shells as part of the ceremony; bride and groom take up the shells and pair them in front of guests. Renditions of painted shells and their boxes are also a popular motif in kimono, lacquerware and ceramic design. At present, one can find scattered and random painted shells in antique shops and homes, and even on eBay, but full antique sets no longer exist. This project establishes the first full, contemporary set to be produced with historical production techniques and is the only full set in existence. Most modern Japanese mistakenly think that the shell-matching game involved matching the painted images, rather than the natural outside of the shell. In 1999, when I was in Kyoto doing research for my historical novel, The Tale of Murasaki, I was able to attend a gathering sponsored by the local Murasaki Shikibu appreciation society, in which we were taught to play the full 360-count traditional shell game. All the ladies (it was an entirely female group) appeared surprised that we were expected to use the natural shell backs as the basis of comparison. All of a sudden, what had seemed a childish amusement, no matter how lovely, became a difficult challenge.

Kō-awase – Incense
Incense and the tools used to prepare and present the fragrance, like the shells with their kai-oke, have given rise to objects of exquisite beauty, as seen in the incense games in the Golden Shells and the Gentle Mastery of Japanese Lacquer exhibition. The origins of the incense competition (kō-awase 香合わせ) are in the aristocratic Heian era (794–1185 CE). Perhaps the most well-known example of an incense competition occurs in The Tale of Genji. In the chapter ‘A branch of plum’ (Umegae), Genji, the ‘Shining Prince’, has created blends that everyone agrees are superior. This scene depicts a time when courtiers blended their own scents according to personal and secret recipes. As it exists today, the ‘incense ceremony’ may still be conducted as a competition, but the focus is different. Codified into the highly ritualised Way of Incense (kōdō 香道), the required tools are aesthetic objects in themselves. Nowadays, the goal is for participants to show they can discriminate between several varieties of aloeswood ( jinkō 沈香) and subsequently to recognise those same scents when they are burned again. It is really a competition of sensitive noses.

The use of lacquer is common to both the shell-matching game and the Way of Incense. The beauty of the objects involved is an important reason that both these artistic pursuits still exist, albeit as somewhat recherché pastimes. Since the invention of plastic, lacquerware has gradually fallen out of everyday household use in modern Japan, but this only serves to heighten its artistic merit when it is used. When a person views the elaborately decorated shell boxes, or handles the utensils of the incense ceremony, they are connecting with some of the most precious and evocative aspects of Japanese artistic heritage.

This article was originally published in the publication Golden Shells and Elegant Games of Japan .