Last updated: 11-21-2019
Did you know that certain portions of Journey to the West were influenced by Indo-Persian and Arab Islamic lore? For instance, in chapter six Sun Wukong and Lord Erlang engage in a magical battle of skill in which they freely transform into myriad animals, each trying to one-up the other. This battle is unusual as Chinese stories going back to pre-Tang dynasty sources show characters could not transform at will. Conversely, One Thousand and One Arabian Nights (1704), which is based on stories as far back as the 9th-century, contains a tale featuring a magical battle of transformations between a princess and a genie. Literary critic C.T. Hsia (1996) notes that the similarities in magical combat “does not mean…the makers of the Monkey legend were specifically indebted to [the Arabian Nights], but it certainly indicates their general awareness of the popular literature of the Middle and Near East” (pp. 132-133).
(I no longer feel Hsia’s (1996) suggestion is accurate. See the 11-21-2019 update below.)
Fig. 1 – (Left) Modern pears grown in molds to imitate ginseng baby fruit. Fig. 2 – (Right)
A 14th to 15th-century illuminated manuscript depicting the women fruit of the Waqwaq tree (larger version).
Additionally, chapters 24 to 26 of Journey to the West features a magical ginseng tree (人參樹, renshen shu) that produces crying, baby-shaped ginseng fruits (人參果, renshen guo) capable of extending the lives of those who eat them to 47,000 years (fig. 1). Chapter 11 of the 13th-century version of Journey to the West features an immortal peach tree with fruits that transform into edible children once they drop into water. Each is capable of answering when asked a question. The concept of speaking, human-shaped fruit most likely comes from tales associated with those from The Book of the Wonders of India (Kitaab Ajaaib al-Hind), a set of Indo-Persian sailor stories collected between 900 and 953. For example, the 37th entry, titled “Deceitful fruit”, reads:
Muhammad b. Babishad told me that, according to what he had learnt from men who had been to the Waqwaq country, there is a large tree there, with round leaves, or sometimes oblong, which bears fruit like a marrow, only larger, and looking something like a human being. When the wind blows, a voice comes out of it. The inside is full of air, like the fruit of the usher. If one picks it, the air escapes at once, and it is nothing but skin (Buzurg & Freeman-Grenville, 1981, p. 39).
The 15th-century Arab historian Ibn al-Wardi took the concept further by describing the fruit as being shaped like voluptuous women (fig. 2) with the power of speech:
On this island are trees that bear as fruit women: shapely, with bodies, eyes, hands, feet, hair, breasts, and vulvas like the vulvas of women. Their faces are exceptionally beautiful and they hang by their hair. They come out of cases like big swords, and when they feel the wind and sun, they shout “Waq Waq” until their hair tears (Toorawa, 2000, p. 393).
Various sources respectively locate this “Waqwaq tree” and its home of “Waqwaq”, a faraway, exotic land or island, somewhere within the Indian Ocean, beyond Iraq, or, further still, beyond China. The Waqwaq term was most likely used to describe the limits of the known world at given times (Toorawa, 2000). The tree itself can possibly be traced to a passage in the Quran (Sura 37, verses 60-64) that describes how the “Tree of Zakkum” produces fruit shaped like the heads of demons. The earliest mention of the Waqwaq tree in Chinese sources appears in the late 8th-century Comprehensive Encyclopedia (通典, Tongdian) by the travel writer Du Huan (杜環). This is apparently based on an earlier Arabic source (A floral fantasy, n.d.).
I was looking through the Ming-era Illustrated Encyclopedia of the Three Realms (三才圖會, Sancai tuhui, 1609) and happened upon a woodblock print of a Waqwaq tree (fig. 3). The image is labeled Dashi Guo (大食國), A term used since the Tang Dynasty to refer to an ancient country in the Arab World (Zhang & Unschuld, 2015, p. 81). This shows the Chinese were still aware of the tree’s foreign origin around the time that Journey to the West was published.
Fig. 3 – Woodblock print from the Illustrated Encyclopedia of the Three Realms showing the Waqwaq tree.
As noted above, Hsia (1996) suggests the battle of transformations between Monkey and Erlang was influenced in some way by Islamic literature. However, Robinet (1979) describes a tit-for-tat battle from Daoist literature that casts doubt on this view:
The Xianyuan bianzhu [仙苑編珠, “Paired Pearls from the Garden of Immortals”, after c. 921] tells how Wang Tan [王探] received “the art of hiding his light and transforming his body.” Dared by someone to metamorphose himself, he took the form of a tree, but the other fellow seized an axe. Wang immediately transformed himself into a stone, but the other lit a fire (in the theory of the five elements, fire prevails over minerals). After turning himself into bubbling water and so on, Wang Tan finally achieved the upper hand by adopting the appearance of a corpse-the man fled immediately (p. 46). 
The way the Daoist and his opponent try to one up the other is very similar to the battle between the Great and Small Sages. Therefore, it’s not a stretch to suggest this story (or related media) was embellished by a storyteller or the author-compiler of the Ming Journey to the West to include two masters of transformation instead of one.
1) I changed the Wade-Giles to Pinyin.
A floral fantasy of animals and birds (Waq-waq). (n.d.). Cleveland Museum of Art. Cleveland, Ohio. Retrieved May 12, 2017, from http://library.clevelandart.org/site…0Waq%20waq.pdf
Buzurg, S., & Freeman-Grenville, G. S. P. (1981). The book of the wonders of India: Mainland, sea and islands. London: East-West.
Hsia, C. (1996). The classic Chinese novel: A critical introduction. Ithaca, N.Y.: East Asia program, Cornell University.
Robinet, I. (1979). Metamorphosis and deliverance from the corpse in Taoism. History of Religions, 19(1), 37-70.
Toorawa, S. M. (2000). WaÃq al-waÃq: Fabulous, fabular, Indian Ocean (?) island(s). Emergences, 10(2), 387-402.
Zhang, Z., & Unschuld, P. U. (2015). Dictionary of the Ben cao gan mu: Volume 2 – Geographical and administrative designations. Oakland, California : University of California Press