In Chinese mythology, the shen or chen (Chinese: 蜃; pinyin: shèn or chèn; Wade-Giles: shen or ch'en; literally "large clam") is a shapeshifting dragon or sea monster believed to create mirages.
Carr (1990:144-145) etymologically hypothesizes that the chen < *dyən 辰 phonetic series (using Bernhard Karlgren's Old Chinese reconstructions) split between *dyən "dragon" and *tyən "thunder". The former words include aquatic shen < *dyən 蜃 "large shellfish; sea dragon", celestial chen < *dyən 晨 "dragon star", and possibly through dragon-emperor association, chen < *dyən 宸 "imperial palace; mansion". The latter ones, reflecting the belief that dragons cause rainfall and thunder, include zhen < *tyən 震 "thunder; shake", zhen < *tyən 振 "shake; scare", and ting < *d'ieng 霆 "thunderbolt".
In the present day, the mythical shen "clam-monster" is best known through the everyday words for "mirage; illusion", typically Chinese haishishenlou 海市蜃樓, Korean shingiru 신기루 蜃氣樓, and Japanese shinkirō 蜃気楼.
The Shuowen jiezi defines ge 蛤 (using a graphic variant with the he 合 phonetic above the radical) as the "category of shen", which includes three creatures that transform within the sea. A que 雀 "sparrow" transforms into a ge 蛤, or muli 牡厲 "oyster" in Qin dialect, after 1000 (commentators say 10) years; a yan 燕 "swallow" transforms into a haige 海蛤 (with "sea") after 100 years; and a fulei 復絫, or fuyi 服翼 "bat", transforms into a kuige 魁蛤 (with "eminent") after it gets old. These kinds of legendary animal "transformations" – hua 化 "transform, change, convert, turn into; metamorphose; take the form of" (see the Huashu) – are a common theme in Chinese folklore, particularly for dragons like the shen. The "dragon's transformations are unlimited", writes Visser (1913:126), and "it is no wonder that Chinese literature abounds with stories about dragons which had assumed the shape of men, animals, or objects.
The Yueling 月令 "Monthly Commands" chapter of the Liji (6, tr. Legge 1885 I:292, 297) lists sparrows and pheasants transforming into shellfish during the traditional Chinese lunisolar calendar. In (Shuangjiang) the last month of autumn, "[jue 爵, a phonetic loan character for que 雀 "sparrow"] Small birds enter the great water and become [ge 蛤] mollusks", and in (Lidong) the first month of winter, "[zhi 雉 "pheasant"] Pheasants enter the great water and become [shen 蜃] large mollusks." While many other classical texts (e.g., Lüshi Chunqiu , Yi Zhoushu, Huainanzi) repeat this seasonal legend about pheasants that transform in dashui 大水 "great (bodies of) water; flood", the Da Dai Liji and Guoyu say they transform in the huai 淮 "Huai River." According to Chinese folklore (Visser 1913:69) swallows are a favorite food of both Chinese long 龍 and shen 蜃 dragons. Read (1934:301) explains, "Hence if people eat swallow's flesh they should not go out and cross a river (dragons will eat them if they do)."
The shape-changing shen is believed to cause a mirage or fata morgana. Shen- synonyms meaning "mirage" include shenlou 蜃樓 (with "multi-storied building", Schafer's 1989:396 "clam castle" or "high house of the clam-monsters"), shenqi 蜃氣 (with qi "breath; pneuma"), shenqilou 蜃氣樓, haishishenlou 海市蜃樓 (with "sea city/market"), and shenjing 蜃景 (with "scenery").
- Carr, Michael. 1990. "Chinese Dragon Names", Linguistics of the Tibeto-Burman Area 13.2:87-189.
- Eberhard, Wolfram. 1968. The Local Cultures of South and East China. E. J. Brill.
- Legge, James, tr. 1885. The Li Ki, 2 vols. Oxford University Press. ISBN 141916922X
- Read, Bernard E. 1934. "Chinese Materia Medica VII; Dragons and Snakes" Peking Natural History Bulletin 8.4:279-362.
- Schafer 1989. "Fusang and Beyond: The Haunted Seas to Japan," Journal of the American Oriental Society 109.3:379-400.
- Schuessler, Axel. 2007. ABC Etymological Dictionary of Old Chinese. University of Hawaii Press. ISBN 0824829751
- Visser, Marinus Willern de. 1913. The Dragon in China and Japan. J. Müller.