Shugendo, which prospered during Japan’s Middle Ages, valued ascetic practices and fused mountain worship with Taoism, Shinto, Buddhism, Animism, astronomy, and medicine. However, since it was transmitted via oral tradition from one generation to the next, limited evidence can be found. Therefore, this essay analyzes 3D imaging data of stone reliefs found at Mt. Hiko, located in the Kyushu region of Japan, to discern whether the carvings depict certain deities and how the Sanskrit characters found in the moon circles represent Shugendo thinking. In addition, it examines how the influence of Shugendo art spread throughout the Kyushu region, Kiyomizu (Kagoshima Prefecture), and Aoki (Kumamoto Prefecture) as well as reassesses its cultural significance. With regard to the former, the results show that a relief of a seated Amitabha was engraved between two other deities: the Mahaasthaamapraapta and Avalokiteśvara. Concerning the latter, the findings reveal that these were the locations of Amitabha worship by the esoteric Tendai sect, which revered “the water” (rivers) and represented an association among Mt. Hiko, Kumano, and Aoki.
I. Introduction: Shugendo and the Kyushu Region
Shugendo, Japanese mountain asceticism-shamanism, incorporates Shinto, Buddhist, and Animistic concepts. Its adherents, called Yamabushi or Shugensha, developed their spiritual experiences through mountain worship. Studies on the practice of this sect have been difficult to conduct due to their somewhat secretive method of oral tradition. Shugendo prospered from the eighth to the nineteenth centuries. However, during the Meiji era (1868–1912), the government established Shintoism as the predominant religion in Japan. State Shinto, which was based on Meiji-era nationalism, considered even Buddhism to be a foreign religion from India and China. As a result, many of the cultural assets of Buddhism were destroyed. In addition, the traditional practice of Shugendo, which respected both Shinto and Buddhism, was strictly forbidden. The oppression by the local government in Kyushu was particularly severe. However, some engraved stone reliefs in the high cliffs of Mt. Hiko have survived. Mt. Hiko is located in the southern part of the Fukuoka Prefecture in Kyushu, Japan. This is one of the three important Shugendo mountains, along with Mt. Haguro in Yamagata Prefecture and Mt. Kumano Omine in Nara Prefecture (fig. 1). This essay analyzes the results of 3D imaging data that recreates Shugendo art from Mt. Hiko. It also examines the influence of the Yamabushi throughout the Kyushu Region, and focuses on the Shugendo culture by drawing upon the author’s knowledge as a sculptor and also as a descendant of the Yamabushi. 3D imaging data of these figures helps to discern whether the carvings of Imakumano Cave depict the three Amitabha deities. In addition, the essay also examines how the influence of Shugendo art spread throughout the Kyushu Region, Kiyomizu (Kagoshima Prefecture), and Aoki (Kumamoto Prefecture), as well as reassesses its cultural significance.
II. Shugendo and Mt. Hiko
Shugendo, which prospered during Japan’s Middle Ages,1 valued ascetic practices (shugyou) and fused mountain worship with Taoism, Shinto, Buddhism, Animism, astronomy, and medicine (fig. 2). Since it was transmitted via oral tradition from one generation to the next, few documents can be found. However, if we examine several stone reliefs found on Mt. Hiko we can understand the Shugendo culture by their expression.
For example, the stone reliefs of Imakumano Cave feature three Sanskrit letters in the Gachirinbonji (moon circle, 250 cm in diameter) as well as two carvings of bodhisattvas (fig. 3). The aforementioned Sanskrit characters are engravings that depict Buddha within a symbolic circular moon.2 These stone reliefs surprisingly indicate their title, client, dedication, and year of production. The inscription on the bodhisattva stone relief indicates that the carvings depict three Amitabha deities and were produced in 1237. Although one bodhisattva stone relief remains in the Imakumano Cave (fig. 4), another (fig. 5) was discovered in a gorge twenty meters away in 1983. Based on these carvings, we can ascertain the names of the Bodhisattva as follows: (A) Mahasthamaprapta Bodhisattva (Seishi-Bosatsu) in a pose of joined hands; and (B) Avalokiteśvara Bodhisattva (Kannon-Bosatsu) as belonging to the lotus. These Bodhisattva images are the two attendants of Amitabha. This is a typical example of the Buddhist’s triumvirate method, wherein two pairs of Bodhisattvas support a central Buddha. Although we can assume that the central Buddha existed, no trace was found of the Amitabha image. However, as a result of this author’s investigation, one of the nearby collapsed rocks had a trace of Amitabha (fig. 6).
According to Satoshi Nagano, 420,000 adherents of Shugendo inhabited the Kyushu Region as well as the Okinawa Region, which is approximately 1000 km south.3 A signature indicates that Yamabushi of Mt. Hiko produced the Sanskrit Character in the moon circle in Kiyomizu in South Kyushu in 1264. This example indicates that the Shugendo faith at Mt. Hiko extended to the Kagoshima Prefecture in the Middle Ages. Moreover, a polished cliff in Aoki (Kumamoto prefecture) contains no inscription for these Sanskrit characters, but a nearby historic landmark is called “Mt. Hiko,” thus suggesting that the Yamabushi of Mt. Hiko participated in its creation.
In the first stage of this study, the author measured 3D images of the Buddhist carvings using a portable scanner,4 which renders a solid image using a 3D printer (figs. 7 and 8).
This laser scanner generates high-resolution data in real time, but it is unsuitable for measuring artifacts that are strictly forbidden to be touched. However, the merit of using 3D data is that it is able to render a solid image while maintaining an accurate ratio. In addition, the advent of portable 3D scanners has been helpful for taking images of, for example, large Buddhist engraved stone reliefs found in harsh environments. In some cases, the stone reliefs are covered with moss and mold, which make it difficult to ascertain the overall shape and size. Furthermore, another advantage of 3D imaging is that it can analyze the overall form with a single color.
In the second stage, the cultural significance at the time of production was clarified by reconstituting the 3D prints. In addition, the Sanskrit characters were measured using a long-range laser scanner. Previous art historical studies that utilized 3D data include those by Shuya Onishi and Akio Hashimoto.5
The Stone Reliefs in Imakumano Cave at Mt. Hiko
There are three peaks at Mt. Hiko: north (Kitadake), center (Nakadake), and south (Minamidake). The Imakumano Cave is situated in Bonjigaiwa Valley near the south peak. In antiquity, Mt. Hiko meant “mountain of the children of the sun god,” which is a name that suggests sun worship. Subsequently, the kanji notation was changed in 819 by a Buddhist priest named Houren and was further changed by Emperor Reigen (1654–1732) to express its excellence. Over time, the forty-nine caves at Mt. Hiko have been likened to the forty-nine palaces of the bodhisattva Maitreya and considered as hallowed ground (Soeda-machi 7–16).
Among the sacred Shugendo mountains, Mt. Hiko (1,199 m) is special since it is located near the Chinese mainland and the Korean peninsula. In fact, the transmission of Buddhism from Mainland China was tied to the ancient animistic worship of Mt. Hiko.6 The oppression of Buddhism during the Meiji Period destroyed many Shugendo artifacts from Mt. Hiko. However, one seven-meter-high stone hokyointo (pagoda, 1817) was saved by converting the Sanskrit characters and the curved lotus flower into designs unrelated to Buddhism. The formative arts of Imakumano Cave yield important clues to the spiritual world of Mt. Hiko. Even the name “Imakumano Cave” is derived from the Ima Kumano Shinto shrine that Emperor Go-Shirakawa Honu erected to invite the gods from other lands to Kyoto in 1160. He also donated twenty-eight manors for this shrine, including Buzen in Mt. Hiko. This evidence indicates that the Kumano faith reached Mt. Hiko (Izumi Yahiro 35).
Few rock faces other than Imakumano Cave feature large-scale engravings since Mt. Hiko was sacred. Viewed from the north peak, the south peak lies west–southwest (magnetic declination 243°). Together, they almost form an east–west line. The star and sun worship of Taoism may have been linked through the north peak in the east. The name of the north peak expresses the polestar faith in China, and the east direction of the peak expresses the sun faith in Japan. The Yamabushi of Mt. Hiko evidently valued the movement and direction of celestial bodies.
The stone tablet with the Sanskrit characters (fig. 9) was produced in 1182 at the foot of Mt. Hiko. This tablet, 146 cm in height, is engraved with the Five Dhyani Buddhas,7 the Buddhas of the three peaks of Mt. Hiko, and a Mandala, wherein each line is carved to form a V-shaped section (yagenbori style). Its Sanskrit characters are clear and powerful. The north peak is represented by Amitabha, the center peak is represented by Sahasra-bhuja (Senjyu-kannon), and the south peak is represented by Sakyamuni. Three reliefs of the image of God of honji suijaku (i.e., the belief that Shinto gods are manifestations of Buddha) in Mt. Hiko were engraved on this tablet. The tablet itself is evidence that esoteric Buddhism and honji suijaku existed at Mt. Hiko during the Heian Period (794–1185).
The inscription in Imakumano Cave expresses two concepts that are important for understanding Mt. Hiko during the Kamakura Period (1185–1333). Following the decoding by Yahiro (1987), three discernible letters can be found using 3D imaging. The weathered portion, which was difficult to read, was recovered using 3D imaging from multiple angles (fig. 10).8 The twelve-line inscription is approximately 79 × 125 cm.
Izumi Yahiro 33It is a Kongo Buddhist priest who served for this work.I offered three degrees prayer whenever I wrote one character when I copied a Lotus Sutra.I produced the three Amitabha divinities on a surface of stone.I made the building for the God of Three Places.I engraved the circular moon into the rock face and engraved Sanskrit characters.These purposes are for Keishun priests, masters, and seniors,And to pray for all without sharing the nobility and the commonalty will be born in Amitabha’s Pure Land.I held a memorial service for the equal benefit of all life in the universe.Middle of June in the third year in 1237.The priest of Ryoukaiin who carved the Sanskrit characters was Kongo Buddhist priest Myoubunbou.
The act described in the second line expresses their devotion and faith to the Lotus Sutra, while the fourth sentence indicates acceptance of the manifestation theory, which is also evident in the third and fifth lines that extol the three Amitabha deities and use Sanskrit characters, respectively. Shugendo art was created in observance of the manifestation theory. In the Imakumano Cave, Amitabha was apparently more important than the manifestation theory since the reference to the three Amitabha deities appears in the first half of the inscription.
III. Regeneration of the Amitabha Relief
The Buddhist reliefs (fig. 4 [A], 5 [B], and 6 [C]) of the Imakumano Cave (fig. 11) were recreated using 3D images to determine whether they were the three Amitabha deities. First, we confirmed the engraved line that formed a double-circular halo in the right corner of the bodhisattva relief (A). This curve is large in comparison with the halo of the bodhisattva relief (B); hence, we decided that the halo did not accompany the bodhisattva image (B), and it is more likely the extended halo of Amitabha. Then, we addressed the engraved halo of the bodhisattva relief (A) from the collapsed rock (C). It was confirmed that the engraved line on the rock (C) matched that of rock (A) when rock (C) was turned 45° counter-clockwise (fig. 12). The line that formed the halo and the aureole of (A) conformed exactly to the line of engraving (C) when we combined the solid printings of (A), (B), and (C). It also confirmed the horizontal line of the pedestal supporting the statue of Buddha (mokakeza), outlines of the knee from the left shoulder, and the halo of the central Amitabha figure (fig. 13). The connection of these elements becomes evident if the central Buddha statue is presumed to be seated. We concluded that the images were the three Amitabha deities: 1) a seated Amitabha with a circular halo in the center; 2) the Avalokiteśvara (Kannon-Bosatsu), holding a lotus flower in the left hand with a mandorla to the right; and 3) the Mahaasthaamapraapta (Seishi-Bosathu), with joined hands and a mandorla to the left.
The author established a scale for the head from the outline of the neck to the right ear and concluded that it was an iconic Amitabha. This Amitabha was reconstructed in reference to another Buddha statue (with the face was sharpened) at Mt. Hiko (fig. 14). Then, the three-dimensional images were reconstituted (figs. 15 and 16). The reconstituted Amitabha was approximately 198 cm high and 136 cm wide. The Mahaasthaamapraapta (A) was approximately 156 cm high and 112 cm wide.
The Mahaasthaamapraapta is engraved with a mandorla on a concave surface, while the Amitabha is engraved in full scale to a depth of approximately 25 cm. The reliefs of these three deities were molded using the corner of the huge rock that was equal to the corner of the rock face so that the protruding central Buddha appeared larger. According to the “Record of Mt. Hiko” (Hikosan-Ruki, thirteenth century), a record that explains the origin and history of Mt. Hiko,9 the three deities were golden in color. Ocher (reddish color from secondary iron oxidation) turns yellow through baking, not from the application of a gold leaf. It was not unusual to color stone reliefs in the Middle Ages, as indicated by the coloration of the stone reliefs of Usuki and Aoki. However, it is still unclear why only the Amitabha was shaved and flattened.
Izumi Yahiro, in the “Mt. Hiko Guide” (1914), determined that the three Amitabha deities remained until the Meiji Period with the sentence “the shadow of the three Amitabha divinities” (Izumi Yahiro 33). This reference would not have used the word “shadow” if the complete Amitabha images remained. During the Haibutsukishaku (literally, “abolish Buddhism and destroy Shakyamuni”) statues of the Buddha were often only partially destroyed. However, in this case, the current rock recently and naturally collapsed.
Information from the 3D printer suggested that the two bodhisattvas belonged to a relief that portrayed three Amitabha deities. However, numerous art historians have noted errors in the clothing of the Mahaasthaamapraapta and have noted that the face of the Avalokiteśvara differs from that of the Mahaasthaamapraapta (Shuya Onishi 110; Izumi Yahiro 39). These inconsistencies might be attributable to differences in the ability of their sculptors and the distance from Kyoto. We also compared the shapes of the faces of both Buddhist statues using 3D imaging. We modeled the Avalokiteśvara (B) using reversed 3D data for half of the damaged head. These were cast in stone powder clay (fig. 17). The top of the head of the Avalokiteśvara (B) is higher than that of the Mahaasthaamapraapta (A) and the face of the Avalokiteśvara (B) is oval with slit eyes. The ridge of the nose and the vertical length of the face of (A) are more pronounced than (B), which indicates that the sculptor of the Avalokiteśvara had greater ability. However, the richness of the body and the rounded baby face of the two bodhisattva images are common. It is possible that the Yamabushi of Mt. Hiko freely interpreted these reliefs and that different sculptors worked on the two bodhisattvas during the same period, based on the differences in the faces as well as the clothing.
IV. The Sanskrit Characters in the Moon Circle from Imakumano Cave
Three 17.5-meter-wide moon circles are carved in yagenbori style that is an incised V-shaped line (fig. 3). These large Sanskrit characters project a compelling presence. Each is engraved in the circular plane reflecting the image of the moon.
The outline of the Sanskrit characters is engraved as a line, while the outside edge is keenly individualized, and the interior is more gentle (fig. 18). As a result, aspects of the Sanskrit characters appear embossed. In addition, the center line in the moon circles is the deepest. In general, the point10 in the moon circle is engraved diagonally, which links the tops of the four corners. However, the point of the Imakumano Cave’s Sanskrit characters is engraved across, thus linking the midpoint of each side and creating an impression of stability. The expression method also helps widen the lines and reduce labor.
The moon circles of the Imakumano Cave are 1.5 times the size of those of Kiyomizu and 2.3 times that of Aoki. The locations for prayer are believed to have occupied both sides of the cave beneath these Sanskrit characters and to have served as the starting point for climbing the cliff. Moreover, we can see the center lines of these moon circles fall directly under the Sanskrit characters and the cliff.
The moon circle of Garbhadhatu Mahaavairocana (Taizoukai-Dainichi) includes a diameter of 269 cm, while that of Shakyamuni has a diameter of 228 cm, and that of Amitabha has a diameter of 200 cm. There is a difference of 41 cm in the diameters of Mahaavairocana and Shakyamuni, and 28 cm in the diameters of Shakyamuni and Amitabha. The Mahaavairocana in the center of the Sanskrit character in the moon circle is clearly the most important, but the reasons for the differences in scale are unclear.
It represents Esoteric Buddhism’s way of seeing the world of cosmos, called the “Diamond World” and the “Womb World.” Garbhadhatu Mahaavairocana in Womb World was centered among the three Sanskrit characters in the moon circle to symbolize Mt. Hiko, whereas the Vajra-dhatu Mahaavairocana in Diamond World (Kongoukai-Dainichi) symbolizes Mt. Houman (829 m) in the Fukuoka Prefecture. The ascetic practices of Yamabushi are called Ten Worlds (Jikkai).11 The first through sixth stages are the six realms for experience of pain of life in Mt. Houman as Kongoukai, the seventh to tenth stages are the four noble worlds for rebirth of soul in Mt.Hiko as Womb World. This hierarchy explains why the Sanskrit character in the moon circle of Shakyamuni in Imakumano Cave was larger than Amitabha. Slight differences in their scales suggest that the Yamabushi may have engraved them for the sake of perspective. The author examined the location and noted that the diameters of the Sanskrit characters in the moon circles of Shakyamuni and Amitabha are almost equal. At present, they are located in the hut preserving the Avalokiteśvara relief, which serves as the starting point for climbing to the relief of the Mahaasthaamapraapta. This location may have been where people prayed to the Sanskrit character in the moon circle.
V. The Cultural Positioning of the Sanskrit Characters in the Moon Circles of Kiyomizu and Aoki
The previous section of this essay examined the stone reliefs found in Imakumano Cave at Mt. Hiko and analyzed the sacred artifacts through 3D imaging. This section focuses on the practice of Shugendo at Mt. Hiko and its influences.
The stone reliefs of Kiyomizu include: 200 Buddhist remnants; five-ring towers; Sanskrit characters in a moon circle, a hokyointo (stone pagoda); and a relief of the Buddha on the rock (tufa, a variety of limestone) measuring 20 × 400 meters (fig. 19). All these reliefs were created from the late Heian Period to the Meiji Period. Three Sanskrit characters in the moon circles stand at a height of 10 meters on the accordion-like rock face (fig. 20). The Bhaisajyaguru (Yakushi-nyorai; the Buddha that is able to cure all ills) is 171 cm in diameter, the Sanskrit character, which means the “Comet” (Keito-sei), is 150 cm in diameter, and the Acala (Fudo-myouou) is 171 cm in diameter. The inscription is damaged, but the topographical record of this Region “The natural beauty spot note of Kawanabe (Kawanabemeishouki, eighteenth century)” reports its content. There were originally five Sanskrit characters engraved by the Yamabushi of Mt. Hiko in 1264.
Hikomatsu Saito estimates that the exfoliated inscriptions were the Sanskrit characters of the solar and lunar eclipse (Lagou-sei) and Vaisravana (Bishamon-ten, the guardian god of Buddhism) (“Survey”). It is said that Bhaisajyaguru, Acala, and Vaisravana were situated to confine comets and eclipses since they were negative omens.
This author analyzed the 3D data for these Sanskrit characters, using laser instrumentation and multi-directional measurement, to search for traces of the collapsed Sanskrit characters.12 Figure 21 shows the Sanskrit characters before it collapsed. Part of the upper-right corner of the Sanskrit characters of the eclipse was relatively undamaged. Only two lines of the Sanskrit character for eclipse remains on the rock.
We cannot confirm the tracing of Vaisravana, which is significantly damaged. An inscription most likely would have been engraved under Vaisravana (the red square of fig. 22). The inscription, based on the study by Hikomatsu Saito (1997), is as follows: “A priest living in □□ [unknown two characters] the Temple of Mt. Hiko. This priest had the will to work, engraving Sanskrit characters. The purpose is a memorial service to benefit all life in the universe equally. February in Kocho Era 4 (1264).”
The phrase “benefit all life in the universe equally” expresses the principle of equality in the Amitabha faith. The inscription of Kiyomizu was supposedly engraved in the space under the Vaisravana to the right. The author of this essay finds a correlation between the accordion-like rock formation of Kiyomizu and the legend that water sprang from an octagonal crystal at Mt. Hiko, because the angles of the accordion formation are approximately 139° (the interior angle of the original octagon is 135°).
Junichi Uemura, a renowned scholar of ancient history, reported that a comet appeared for extended periods from July to December 1264 (Junichi Uemura 6). The Sanskrit characters in the moon circles of Kiyomizu would be completed five months from the date that the comet appeared in the historical records. The Kocho Era became the Bunei Era (the reign of another emperor) on 28 February 1264. It is difficult to believe that the date in the inscription was erroneous. The Yamabushi of Mt. Hiko reacted to the incident with alacrity and had little time to create the Sanskrit characters in the moon circles, especially since the distance to Kiyomizu was 240 km. In addition, perhaps the Sanskrit character for the comet was not the actual comet. When these characters were carved in Mt. Hiko and Kiyomizu, the Mongolian army attacked the Korai Dynasty and southern Song near the Kyushu region in Japan, and it is supposed that the Sanskrit characters were negative omens expressing the imminent Mongolian invasion.
The Sanskrit characters in the moon circles of Aoki represent the Shinto and Aoki Kumano shrines, located near the Kikutchi River in Kumamoto Prefecture. Multiple Sanskrit characters in moon circles measuring 6 × 15 m2 are engraved on the tuff (fig. 23). Tradition would have extended them to 20 m, but the surface of the northern rock was insufficient. Five large rocks collapsed in a state that maintained a vertical direction. Red coloration that remains on parts of the tuff was likely intentional, because unlike andesite, tuff does not discolor red. There are twelve Sanskrit characters in the moon circle on this rock face (fig. 24).
Natsuki Tazoe and Hikomatsu Saito decoded the images: 1 is Shakyamuni; 2 is Amitabha or Avalokiteśvara (Senju Kannon); 3 is Kulikah (Kurikara-ryuou; Dragon God); 4 is the Vajra-dhatu Mahaavairocana (Kongoukai Dainichi); 5, 6, and 7 are the three Amitabha divinities (Amitabha, Avalokiteśvara, and Mahaasthaamapraapta); 8 is Amoghasiddhi (Fukujoju-nyorai); 9 is Om (the word uttered as an incantation); 10 is Shakyamuni; 11 is Bhaisajyaguru (Yakushi-nyorai); and 12 is A-Bira-UnKen (mystical Sanskrit sound of Mahaavairocana).13 No inscription reveals the date and sculptor; Natsuki Tazoe and Hikomatsu Saito presume Tendai priests engraved these Sanskrit Character in the moon circle during the Kamakura Period.14 Dousei Nishida (2013) noted that the Yamabushi of Mt. Hiko were concerned with producing Kulikah Sanskrit Characters (23–34).
A small shrine (fig. 25), called “Mt. Hiko,” stands by the hilltop district 500 m from Aoki, and local inhabitants still worship there. It is thought to be connected with the Shugendo of Mt. Hiko since the granite in the small shrine is found in the Kumano Shrine of the Sanskrit character in the moon circle of Aoki.
The author recreated the arrangement of the Sanskrit characters in the moon circle in Aoki at the time of their production using drawings supplied by the Tamana Board of Education (fig. 24). The representation of the three Amitabha deities apparently was important in Aoki since they occupy the highest position in the arrangement. Dousei Nishida stated that the members of the esoteric Buddhist Jodo sect engraved the Sanskrit characters because the Yamabushi would have never engraved the three Amitabha deities together (33). However, this author surmises that two groups of Yamabushi from Mt. Hiko produced the Sanskrit characters in the moon circles of Aoki, since there are the stone reliefs of the three Amitabha deities in Imakumano Cave as well as in Kulikahh15 Cave (Kulikahra-kutsu: currently named Tamayakutsu) at Mt. Hiko.
As noted, the Kumano faith (Nara Prefecture) reached Mt. Hiko in 1180 during the late Heian Period. In fact, Mt. Hiko and Kumano share three commonalities: their important Buddha statue was Amitabha, they were the locales of the esoteric Tendai (the Buddhist sect from China), and both revered “the water” (river). This author therefore sought links among Mt. Hiko, Kumano, and Aoki. The primacy of Amitabha is the first link. The center shrine of Kumano occupies the sandbanks of three rivers, which were removed and rebuilt after a flood during the Meiji Period. Thought to be the Jodo of the Amitabha,16 this was the location for contemplating death. The preeminent Buddha at Mt. Hiko is the Amitabha of the north peak, who was engraved in Aoki. The second link is the relationship with the Tendai. The guides for Emperor Go-Shirakawa (1127–1192) regarding Kumano were the Yamabushi of the sect. Relationships with the sect are evident in the “Record of Mt. Hiko” (Hikosan-ruki), wherein it states that the God of Mt. Hiko came from Mt. Tendai in China (Soeda-machi 17–20). Thus, the Sanskrit characters in the moon circles of Aoki were influenced by the Tendai sect. Finally, the third link is their shared reverence for water (rivers). As stated earlier, Kumano occupies the sandbanks of three rivers, of which Aoki is adjacent to the Kikuchi River, and Kiyomizu is near the river where the accordion-like rock is located. All three locations are situated west of their respective rivers, which is the direction of Buddhist paradise, where the dead go in their afterlife. The legend concerning the beginnings of Mt. Hiko in the “Record of Mt. Hiko” states that the first sword of octagonal crystal came to Kulikahh cave from the sky. Kulikahh (the God of Dragons) appeared bearing a precious stone in its mouth and the sacred water flowed from this cave (20–24). Importantly, we should note that Mt. Hiko is the God of Mikumari (distribution of the water), and the Sanskrit character for Kulikahh at Aoki is the largest (353 × 123 cm). It is rare that Sanskrit character of Kulikah, which is a guardian of the Acala, is engraved large-scale like this. Given this evidence for the correlations among Kumano, Mt. Hiko, and Aoki, it is possible that the Yamabushi of Mt. Hiko, who regard Kulikah as important, engraved the Gasurinbonji of Aoki.
The Sanskrit characters in the moon circles of Aoki (fig. 26) can be distributed by considering a difference in their production methods: Period 1-A ((5), (6), and (7)); Period 1-B: ((4), (8), and (10)); Period 2-A: ((1), (2), and (3)); and Period 2-B: ((9) and (12)). Considering whether the Yamabushi of Mt. Hiko produced it, this section examines the cultural background of the Sanskrit characters of Aoki.
Period 1-A: the Sanskrit characters in the moon circles here have relatively strong expressions engraved in yagen-bori style, especially in the circle reflecting an image of the moon 80 cm in diameter. Traces of a 1-cm-wide flat chisel remain on these moon circles. These are believed to be the three Amitabha deities ((5), (6), and (7)) with the altar supporting a principal Buddha statue on the highest position. The group in figure 12 ((5), (8), (10), and (11)) supposedly expresses the four Buddhas of Exoteric Buddhism (Kengyo) that follow four directions. However, Amoghasiddhi, who follows the north direction, was replaced by Maitreya due to the influence of the four Buddhas of the Esoteric Buddhism (Mikkyou) of Vajra-dhatu Mahaavairocana.17
Period 2-A: a group of colored Sanskrit characters engraved in a relatively narrow line: Shakyamuni (1); Amitabha (2); and Kulikah (3). According to Saito (1979), the Sanskrit characters in the moon circles (1) and (2) are the combination of Buddhas to transport those to the Buddhist paradise of Amitabha. In addition, Kulikah (3) is an incarnation of the Acala, and it is said that the Acala protects the dead from being possessed by evil spirits (Yushou Miyasaka 27–29). The author refers to this Sanskrit character as the Kulikah and not that of the Acala. As stated earlier, Kulikah is the Dragon God that guards an important cave in the beginning of Buddhism at Mt. Hiko. There are many stone reliefs depicting the Sanskrit character of the Acala in Japan, like Kiyomizu. However, there is no Sanskrit character for Kulikah other than that for Aoki (Dousei Nishida 23–34). Since the engraving of Kulikah was so daringly placed there, the producers of Aoki are assumed to have been conscious followers of Shugendo from Mt. Hiko. Finally, the Kulikah Sanskrit characters are the most decorative. The lotus position was also engraved under the Sanskrit characters of Kulikah, thus indicating that Kulikah was highly regarded in Aoki. These Sanskrit characters ((1) (2) (3)) share the light carving, decorativeness, and coloration of the Sanskrit characters in the moon circles of Mt. Hiko. If they were produced at the same time as those of Mt. Hiko, then these Sanskrit characters would have been inscribed during the middle Kamakura Period.
Period 2-B: the Sanskrit characters in the moon circles of A (om)18 -Bira-Un-Ken (9) and (12) share the style and coloration of carvings produced during Period 2-A. The Sanskrit characters (9) feature only circular lines, unlike those engraved on a plane in a circle. It includes the beginning of the mantra (words repeated by a Buddhist priest) for Garbhadhatu Mahaavairocana (fig. 26, solid blue line). This is located at the same height as Kulikah (fig. 27). The Yamabushi of Mt. Hiko possibly engraved them, since Garbhadhatu Mahaavairocana symbolizes Mt. Hiko and the Sanskrit characters of Garbhadhatu Mahaavairocana are centered on the Imanokutsu of Mt. Hiko. The 3D molding characteristics of the Sanskrit characters of Periods 1-A and 1-B resemble Kiyomizu more than those of Mt. Hiko. Thus, Periods 1-A and 1-B were engraved in the middle Kamakura Period, while Periods 2-A and 2-B were engraved in the late Kamakura Period.
Many ancient tombs surround the Kikuchi River near Aoki. During the latter half of the third century to around the seventh century, ancient people transported tufa, used for sarcophagi, down the Kikuchi River (Kyoji Takagi). In addition, the surrounding population had regularly traded with China since the Heian Era, and they made iron (using the sand from Mt. Shoudai, located near Aoki) and exported ironworks such as swords.19 In this regard, the ochre coloration of the carvings could have been produced by sculptors’ iron tools. Moreover, active trade with the Chinese during the Kamakura Period would have brought influences there. There is also a high probability that the motive for creating the stone reliefs originated from relations between China and Japan, especially since trading between the two countries mostly occurred at the port of Hakata in the Kyushu Region.
Furthermore, the stone reliefs of Imakumano Cave were created in 1237, while those of Kiyomizu were created in 1264. During that time span, the Mongolian army attacked the Korai Dynasty (1231–1273) and southern Song (1235–1279). The Mongolians also attacked northern Kyushu in the Bunei Invasion (1274) and the Koan Invasion (1281). It is from these conflicts that widespread anxiety might have spurred the creation of the stone reliefs. Perhaps the Sanskrit characters were negative omens expressing the Mongolian invasion, thus explaining why the getsurin bonji of Kiyomizu were completed earlier than the actual appearance of a comet. Since a comet appeared after the completion of Kiyomizu, the faith of the Hikosan might have increased. Similarly, the abandoned area of Kiyomizu at the mouth of the Manose River (of which its upper reaches were called the Kiyomizu River until the Showa Period) was a trade route with China in the Middle Ages.20 Furthermore, due to the trade between these two countries, and anxiety due to the civil war in China (between the Song and Yuan) and the Mongolian invasions, the correlation between Shugendo and the Amitabha faith, a strong awareness of death, and the importance of water, specifically rivers. This study employed 3D data to examine the Stone Reliefs of Imakumano Cave, Kiyo. Conflicts (such as the Mongolian invasion) might have increased the practice of Shugendo at Mt. Hiko.
This study employed 3D imaging data to examine the stone reliefs of Imakumano Cave, Kiyomizu, and Aoki, especially the Sanskrit characters on the various rock faces. In addition, images from the collapsed rock were restored to their original state using a 3D laser printer. As a result, we can conclude that a relief of a seated Amitabha was engraved between the Mahaasthaamapraapta and Avalokiteśvara. The three Amitabha deities were carved using a convex shape equal to the corner of the rock so that the primary Buddha statue appears larger.
The author also measured the diameter of the moon circles and ascertained that the Sanskrit characters of the central Garbhadhatu Mahaavairocana (Taizoukai Dainichi-nyorai) were the largest. Characters pertaining to the Buddha were the second-largest, and those for the Amitabha (on the right) were the smallest. This difference in scale was attributed to various levels of importance and the plurality of prayer locations. Regarding the Sanskrit character in the moon circles of Kiyomizu, which the Yamabushi of Mt. Hiko produced, the author investigated the cultural background using 3D imaging data. The findings showed that these were locations of Amitabha worship by the esoteric Tendai sect, which revered “the water” and represented an association among Mt. Hiko, Kumano, and Aoki.
This essay also suggests the possibility that the Sanskrit character in the moon circles of Aoki embodied the worldview of the Shugendo faith at Mt. Hiko. Moreover, this essay examined a group of twelve Sanskrit characters and divided them into the following characteristics: Amitabha faith; four Buddhas of Exoteric Buddhism; the manifestation theory; regard for Kulikah; and Shingon of Garbhadhatu Mahaavairocana. Finally, the results indicate that the influence of Shugendo and its arts at Mt. Hiko spread throughout the Kyushu Region for various reasons, which include possible anxiety due to the civil war in China (between the Song and Yuan) and the Mongolian invasions, the correlation between Shugendo and the Amitabha faith, a strong awareness of death, and the importance of “the water” (rivers).
However, the following questions remain. Why did the Yamabushi of Mt. Hiko not engrave an inscription to communicate that the Buddhist stone reliefs in Aoki were created by them? Was the structure progressively carved or did the inscription disappear after the collapse of the northern rock? In the future, the author will continue to investigate these questions, as well as delve deeper into the relation between the Shugendo art of Mt. Hiko and the Kyushu Region.
Dousei Nishida. “A Study of Magaibonji of Aoki.” History Tamana 61. Kumamoto, Japan: The Society for the Study of Tamana History, 2012. 23–34.
Hikomatsu Saito. “A Study of the Carved Sanskrit Letters in Aoki Cliff.” Religious Studies in Japan 52. 3 (1979): 288–290
Hikomatsu Saito. “Survey of the Stone Relief in Kiyomizu.” Kawabe-cho Cultural Assets Working Papers. The Board of Education of Kawanabe, 1997.
Hitoshi Miyake. The World of Enno-Gyouja and Shugendo. Exhibition catalogue. Tokyo: Mainichi Newspapers, 1999. 171–175.
Izumi Yahiro. “The Stone Relief in Three years in Katei era of Imakumano Cave.” Shugendo of Mt.Hiko Display Document. Fukuoka, Japan: Bunrindo, 1987.
Junichi Uemura. “A Consideration about the Motivation to Produce the Stone Relief in Kiyomizu.” Journal of the Society of Human History 9 (1997): 1–7.
Kyoji Takagi. “Kofun of Kikuchi River Basin.” Bulletin of the National Museum of Japanese History 173. Tokyo: Rokuichi Shobo, 2012. 521–523.
National Museum of Japanese History. “Report of the Fifth Society for the Study About the Manose River Basin.” 2007. https://www.rekihaku.ac.jp/research/list/joint/pdf/narichu03_f_r.pdf. Accessed 13 Jun 2017.
Natsuki Tazoe, C.R. Magaibonji of Aoki. Kumamoto, Japan: The Committee for Cultural Properties Protection in Tamana city, 1971.
Satoru Kitago. “Woman from 3D data to Bronze Casting.” Ragusa and Rokuzan Ogiwara. Tokyo: Rokumonsha, 2010. 40–41.
Shuya Onishi. “Magaisekibuthu and Kongo Buddha Statue.” Mt. Hiko Excavation. Fukuoka, Japan: Ashishobou, 1983.
Shuya Onishi, The Study on the Reconstruction and Preservation of Japan-Korea Ancient Sculpture (Results of Research Report). Fukuoka, Japan: Kyushu University Production, 2006.
Soeda-machi. Hikosan-ruki. Fukuoka, Japan: Ashishobou, 1993.
Sogeisha. Introduction to Sanskrit Characters. Kyoto, Japan: Sogeisha, 1967.
Susumu Ishii. The Stone Buddha Statue and Tower. Tokyo: Yamakawa Publishing Company, 2001.
Tamana City History Museum Kokoro Pia. Tamana-shi History Complete history First Book, Tamana-shi. Kumamoto, Japan, 2005.
Yushou Miyasaka. “Kogyo Daishi no Jyoudokan.” Modern Esoteric Buddhism 4. Kyoto, Japan: Chishakuin, 1992. 27–29.
This essay situates the Middle Ages from the end of the twelfth to the end of the sixteenth centuries, the period wherein lord of the manor territoriality existed in Japan. Regarding the establishment of Shugendo, it is said that it came from one religion sometime in the latter half of the Heian Era. See Hitoshi Miyake, The world of Ennogyouja and Shugendo 171.
Gechirin in Buddhism is a full moon, the symbol of absolute being. It expresses Buddha and the wisdom of Buddhism.
Regarding the Sanskrit characters in the moon circles of Kiyomizu, two Sanskrit characters on the right and the inscription collapsed, but the inscription (Kawanabemeishouki) from the Kansei era was recovered using digital technology (1789–1801).
Portable scanner; EXAscan™ (Creaform), 3D printer; ZPrinter® 650 (3D Systems), Long-range laser scanner; FARO® Laser Scanner Focus3D (FARO).
Please see Shuya Onishi and Satoru Kitago.
There is a legend that Zenshou Buddhist priests began Buddhism in Mt. Hiko.
The five Dhyani Buddhas or Five Wisdom Tathāgatas include: Aksobhya (east); Amoghasiddhi (north); Vairocana (meditator); Ratnasambhava (south); and Amitābha (west).
The kanji to express “etc.” and “carving” are expressed in a variant character.
Appears in the “The Record of Mt. Hiko” in 1213, but a debate continues over when it wasit was actually written, since there was a description of the stone relief at Imakumano Cave in 1237.
Kuten is an upper point on Sanskrit characters that expresses a nasal sonant. Nehanten is a point on the right of Sanskrit characters expressing an aspirated sonant. Shuugyouten is a signifier on the right shoulder of Sanskrit characters expressing a long sonant. See Sougeisha, Introduction to Sanskrit Characters 3–4.
The ten phases are the worlds of hell, hungry spirits, animals, Asura, humans and heaven, as well as the worlds of voice-hearers, cause-awakened ones, Bosatsu and the spiritual realm of Buddhahood.
3D data measurement: Hisanaga Co., Ltd. and the Minamikyushu-shi Board of Education.
The mantra of the Garbhadhatu Mahaavairocana (Taizoukai-Dainichi) is designed in the shape of a stone pagoda (Gorinto).
Shingon esoteric Buddhism regards Mahaavairocana. Tendai esoteric Buddhism tend to respect to the various Buddhas.
Kulikah is the Dragon God as incarnation of Acala. This is expressed as the fire around the sword of Acala.
Manifestation theory of Kumano is Amitabha (center shrine), Bhaisajyaguru (new shrine), and Avalokiteśvara (Nachi shrine).
The four Buddhas of Exoteric Buddhism (Kenkyo) guard directions: Bhaisajyaguru (Yakushi-nyorai) guards east, Shakyamuni guards south, Amitabha guards west, Maitreya guards north. The Four Buddhas of Esoteric Buddhism of Vajra-dhatu Mahaavairocana (Kongoukai Dainichi-nyorai): Akshobhya (Ashuku-nyorai) guards east, Ratnasambhava (Houshou-nyorai) guards south, Amitabha guards west, Amoghasiddhi (Fukujyojyu-nyorai) guards north. The Four Buddhas of Exoteric Buddhism of the Heian period are sometimes replaced by affections of Esoteric Buddhism. Susumu Ishii The Stone Buddha Statue and Tower.
“Om” is a sacred sound in India from ancient times.
See Tamana City History Museum, Kokoro Pia. Tamana-shi history complete history first book, Tamana-shi 147–151, 431–436.
Please see National History Folk Museum, “Report of study about the Manose River Basin.”