Last updated: 09-07-2023
The Six-Eared Macaque (Liu’er mihou, 六耳獼猴) (fig. 1) is one of the most interesting villains that Sun Wukong faces in Journey to the West (Xiyouji, 西遊記, 1592). He is an example of the evil twin archetype from world mythology. But unlike modern media which sometimes differentiates evil twins with goatees,—think of Evil Spock from the Star Trek episode “Mirror, Mirror“—this malicious spirit is an exact duplicate of Monkey with the same features, voice, clothing, and fighting abilities. He’s so similar in fact that no one in the cosmos, save the Buddha, can differentiate him from Wukong. But who is he really and where did he come from?
In this article, I suggest that the Six-Eared Macaque is a negative manifestation of Sun Wukong’s mind, a concept which is based on Buddhist theories of mind and nonduality (Sk: advaya; Ch: bu’er, 不二). In addition, I describe his character arc and appearance, discuss his possible origin within the book as a former sworn brother of the Monkey King, explain the significance of the six ears to Buddhism, and detail references to him in a 17th-century sequel to Journey to the West. Finally, I describe the character’s influence on the upcoming Chinese video game Black Myth: Wukong (Summer of 2024).
Fig. 1 – The Six-Eared Macaque by Zhang Ji (larger version).
1. Description of the Episode
In chapter 56, Monkey magically disguises himself as a 16-year-old monk and comes to the rescue of Tripitaka, who had been captured by mountain bandits demanding money for safe passage. The bandits let the priest go under the pretense that his young disciple has money. However, Wukong murders the two bandit chiefs with his magic staff, causing the remaining thirty or so men to flee in terror. That night, the pilgrims find lodging with an old couple. But they soon discover that the couple’s son is one of the bandits routed by Monkey earlier in the evening. The son returns home with his gang late at night and, upon learning of the monks, hatches a plan to attack them in their sleep. But the old man alerts the pilgrims to the danger and allows them to escape out a back gate. The bandits take chase, catching up to them at sunrise, only to meet their death at Wukong’s hands. Monkey finds the old couple’s son and beheads him as punishment for disrespecting his parents. All of this killing horrifies Tripitaka, who recites the tight-fillet spell (jin gu zhou, 緊箍咒) and banishes Wukong from the group.
In chapter 57, Wukong travels to Guanyin’s island paradise to complain about Tripitaka casting him out from the pilgrimage. He asks the goddess if he can be released from monkhood and return to his old life, but she instead uses her eyes of wisdom to foresee a future event in which Monkey will need to rescue his master. Meanwhile, Tripitaka asks his remaining disciples to find him food and drink. However, in their absence, Wukong attacks the priest, knocking him unconscious with the staff and stealing the group’s belongings containing the travel rescript (tongguan wendie, 通關文牒).  Sha Wujing is sent to the Mountain of Flowers and Fruit to retrieve their things, but Monkey refuses to return the rescript as he wishes to win all of the merit and fame by finishing the quest on his own. Wujing points out that the Buddha will only give the holy texts to the chosen scripture seeker. Wukong, however, shows that he’s prepared for this outcome by parading doppelgangers of Tripitaka, Zhu Bajie, Sha, and the white dragon horse. Wujing kills his double (which is revealed to be a transformed monkey spirit) and attempts to attack Monkey but is forced to retreat. He flees to Guanyin only to attack Wukong once more when he finds him sitting next to the goddess. Guanyin stays his hand and explains that Monkey has been with her the entire time. She then sends them both back to the Mountain of Flowers and Fruit to investigate the double.
In chapter 58, upon seeing the impostor, Wukong rushes forward to attack the double, who defends himself with his his own magic staff. The two battle their way through the sky to Guanyin’s island paradise in order to determine who is the real Monkey. But when she attempts to weed out the impostor by reciting the tight-fillet spell, both Wukong’s drop to the floor in pain. In the face of failure, Guanyin sends them up to the celestial realm in the hopes that the deities who fought Monkey centuries ago will be able to tell one from the other. Both of them fight their way into heaven and gain an audience with the Jade Emperor, but not even the imp-reflecting mirror (zhao yao jing, 照妖鏡)  can tell them apart. The two then battle their way back to earth, and when Tripitaka’s use of the tight-fillet spell fails, they fight down to the underworld. There, the judges are unable to find the impostor in their ledgers, but “Investigative Hearing” (Diting, 諦聽), the omniscient celestial mount of the bodhisattva Ksitigarbha, finally solves the riddle. However, the creature is reluctant to reveal the false Wukong for fear he will use his powers to disrupt the underworld. The bodhisattva therefore sends them to the Western Paradise in India to stand before the Buddha, who instantly recognizes the impostor. The Enlightened One gives Guanyin a short lecture on four spiritual primates that fall outside of the ten categories of mortal and immortal life in the cosmos: 1) The Stone Monkey of Numinous Wisdom (Lingming shihou, 靈明石猴, i.e. Sun Wukong); 2) The Red-Buttocked Horse Monkey (Chikao mahou, 赤尻馬猴); 3) The Connected Arms Gibbon (Tongbi yuanhou, 通臂猿猴); and 4) The Six-Eared Macaque (Liu’er mihou, 六耳獼猴). When the Buddha identifies the doppelganger as the fourth kind, the fake Monkey attempts to flee in the form of a bee but is trapped under the Enlightened One’s alms bowl. In the end, Wukong kills the macaque with his staff.
2. His Appearance
Chapter 58 describes Six Ears as Sun’s exact twin:
His looks were exactly the same as those of the Great Sage: he, too, had a golden headband clamped to his blondish-brown hair, a pair of fiery eyes with golden irises, a monk’s robe on his body, a tiger kilt tied around his waist, a gold-banded iron staff in one of his hands, and a pair of deerskin boots on his feet. He, too, had
A hairy face with the Thunder Lord’s beak, 
Empty cheeks unlike those of Saturn; 
Two forked ears on a big, broad head,
And fangs that have grown outward (based on Wu & Yu, 2012, vol. 3, p. 104).
His magic staff, the “Acquiescent Iron Pole Arm” (Suixin tie ganbing, 隨心鐵桿兵),  also mirrors Monkey’s weapon. “Acquiescent” or “to fulfill one’s desires” (suixin, 隨心) is a play on the “as-you-will” (ruyi, 如意) of Sun’s “As-You-Will Gold-Banded Staff” (Ruyi jingu bang, 如意金箍棒).
3.1. Background in the novel
Lam (2005) suggests that the Six-Eared Macaque is actually Monkey’s sworn brother, the Macaque King (Mihou wang, 獼猴王) (fig. 2), from his younger days as a demon (p. 168).  He explains:
The latter’s other agnomen, “the Great Sage Informing Wind” (Tongfeng dasheng, 通風大聖 …)  suggests further that its ears are as good as the six-eared macaque’s in information gathering. Despite all these archaic or anachronistic traces, however, Monkey never comes to recognize the six-eared macaque as his old sworn brother as is the case with the Bull Demon King” (Lam, 2005, p. 168).
The novel doesn’t mention the original home of the Macaque King, only that Wukong “tour[ed] the four seas and disport[ed] himself in a thousand mountains” (Wu & Yu, 2012, vol. 1, p. 138). He could live in any one of these places.
Fig. 2 – A Zbrush rendering of the Macaque King by Zcool user Nerv99 (larger version). Image found here.
[Note (08-05-23): For the sake of discourse, I have altered the wording in this section from “Lam (2005) reveals” to “…suggests” to show that I’m open to opposing views.
It has recently come to my attention that some people disagree with Lam’s (2005) statement from above. One anonymous person on Tumblr even questioned my credibility because they believed that I—not realizing that this is not my idea—was confusing two different characters. But I replied by saying:
It’s okay to disagree with someone. I don’t always agree with scholars who write about Journey to the West and its characters. But that doesn’t make them untrustworthy. The most important thing to do in such situations is to present your own views and support them with evidence.
Admittedly, this person subsequently contacted me in private to ask questions about the subject. So my respect goes out to them.
Another person (who shall remain nameless) has repeatedly said on social media that Lam’s (2005) statement is “just a theory” and that the Macaque King is never explicitly stated in the book to be Six Ears. In addition, they claim the idea that Macaque and Sun Wukong were sworn brothers is not widely accepted in China. Instead, the Chinese supposedly view them as biological brothers. But I have three problems with this critique. One, saying that something is just a theory does not address the point raised by Lam (2005). As noted above, anyone who disagrees needs to provide a counterargument with cited evidence. Two, just because something isn’t openly stated doesn’t mean there isn’t a connection between two or more concepts. See, for instance, the unspoken relationship between the supply cart in chapter 46 and Daoist internal alchemy. And three, the views of modern readers carry no weight when we are talking about an allegory-laden novel that was published over 430 years ago. This is especially true since framing Six Ears and the Monkey King as brothers is incorrect (see section 3.3 below for how these two are connected). Therefore, the only thing that matters in this case is evidence gleaned from the book.
But to the person’s credit, they (along with others on social media) provide a reason for why they don’t accept Lam (2005): Six Ears can’t be the Macaque King because the latter is a woman. This idea is always mentioned in passing but never actually supported with evidence. However, I show in this article that the concept is based on a discrepancy in the Anthony C. Yu (Wu & Yu, 2012) translation. My conclusion reads:
Journey to the West uses the term Mihou wang (獼猴王) three times to refer to the same character. Yu (Wu & Yu, 2012) translates this twice as “Macaque King” (ch. 3 & 4) but later changes it to “Female Monkey King” (ch. 41). Despite the original Chinese referring to the character as the “fifth brother” (wuge, 五哥), Yu (Wu & Yu, 2012) appears to represent them as a woman based solely on the association of mihou (獼猴) with female monkeys. However, not even Journey to the West follows this association, for out of 13 mentions of the term, over 61% refer directly to Liu’er mihou (六耳獼猴), Sun Wukong’s six-eared doppelganger. In addition, mihou (獼猴) and mi (獼) are even used in the novel to refer to monkeys as a whole.
The term mihou (獼猴) is just one of several transcriptions for a non-Chinese word used in China for millennia to mean “macaque” or “monkey.” Dynastic sources show that the association with female monkeys is a misunderstanding based on changes in dialect, along with differences in transcription. Said changes include muhou (沐猴, “bathing monkey”), muhou (母猴, “mother monkey”), and of course mihou (獼猴). Therefore, the word can be applied to either male or female monkeys.
The last point is exemplified in Buddhist literature. A 3rd-century CE Chinese version of the Dasaratha Jataka, which retells the Hindu epic Ramayana (5th-century BCE), references the great battle between the monkey king brothers Sugriva and Vali and calls the former Mihou (獼猴). A 3rd-century Chinese version of the Mahakapi Jataka, which tells of the Buddha’s past life as a monkey king, also refers to him as Mihou wang (獼猴王). And a 5th-century variant of the same story refers to the Enlightened One as the Shan mihou (善獼猴), or “Good Macaque.”
[Note (09-27-23): Even Sun Wukong’s precursor, Hou xingzhe (猴行者, the “Monkey Pilgrim”) from the 13th-century JTTW, is called Mihou wang. Chapter two refers to him as Huaguo shan ziyun dong bawan siqian tongtou tie’e Mihou wang (花果山紫雲洞八萬四千銅頭鐵額獼猴王, the “Bronze-Headed, Iron-Browed King of the Eighty-Four Thousand Monkeys of the Purple Cloud Grotto on the Mountain of Flowers and Fruits”) (Wivell, 1994, p. 1182).]
Therefore, this is not a valid counterargument.
I know of one other objection appearing on social media: Sun Wukong wouldn’t have killed Six Ears if he had recognized him as his sworn brother. But people who claim this forget that Macaque is capable of transformations due to his connection to the Monkey King (again see section 3.3. below). This fact is revealed at the end of his character arc in chapter 58: “The macaque’s hair stood on end, for he supposed that he would not be able to escape. Shaking his body quickly, he changed at once into a bee, flying straight up” (Wu & Yu, vol. 3, p. 116). Thus, he could have taken on a different form in the past. Someone might counter that Sun would have seen through this magic disguise with his “Fiery Eyes and Golden Irises” (Huoyan jinjing, 火眼金睛).  But the fraternal brotherhood with the Macaque King and the other Demon Kings is formed in chapter three, while Monkey isn’t punished to the eight trigrams furnace, which gives him this power, until chapter seven (Wu & Yu, 2012, vol. 1, pp. 138-139 and 189). Remember also that even with his holy vision, Sun can’t see through Six Ears’ disguise during their struggle across the cosmos. Therefore, I don’t consider this to be a valid counterargument either.
It appears that most of this hubbub can be traced to “Shadowpeach,” a nickname for a popular slash romance between the Lego Monkie Kid versions of Six Ears (Shadow) and Sun Wukong (Peach). Somehow this is validated if the Macaque King and Six Ears are two different people. I’m not exactly sure why. But trying to discredit me or a source just to support a popular headcanon seems extremely immature to me.]
3.2. Significance of the Six Ears
Yu (Wu & Yu, 2012) suggests that the macaque’s six ears come from the Buddhist saying “The dharma is not to be transmitted to the sixth ear [i.e., the third pair or person]” (fa bu zhuan liu er, 法不傳六耳) (p. 387 n. 7). He continues: “This idiom is already used in chapter 2 when Monkey assured Patriarch Subodhi that he could receive the oral transmission of the secret formula for realized immortality because ‘there is no third party [sixth ear] present'” (Wu & Yu, 2012, vol. 3, p. 387 n. 7). This phrase refers to a closely guarded secret that must be kept at all cost, something that can only be passed from a qualified teacher to an initiated disciple.
In this case, the Six-Eared Macaque is the third set of ears, for the Buddha states:
[E]ven if this monkey stands in one place, he can possess the knowledge of events a thousand li [(310.7 mi/500 km] away and whatever a man may say in that distance (based on Wu & Yu, 2012, vol. 3, p. 115).
Who knows how long this creature listens in on Monkey’s life before he makes an appearance. Perhaps he hears Subodhi’s secret teachings. This might explain why the impostor has similar abilities to our hero.
[Note: See the 08-18-23 update below for more information.]
As the embodiment of the “sixth ear,” the Six-Eared Macaque also represents heterodoxy (waidao, 外道; pangmen, 旁們, lit: “side door”), for someone eavesdropping on esoteric secrets without full initiation into a tradition would have an incomplete understanding. And any supernatural gifts derived from subsequent practice, though powerful as they may be, would just be pale imitations of that achieved by true disciples. This concept is featured in chapter 46 when three animal spirits-turned-Daoist priests challenge Wukong to contests of torture, but each dies because their magic is not as strong as Monkey’s. The novel stresses this is because their training was only partially completed under a teacher.  Wukong is more powerful because he completed his training under Subodhi.
3.3. The Ramayana vs. Buddhist Philosophy
Hoong (2004) claims that the concept of two identical apes fighting each other “evolved from the well-known episode of the Ramayana where Rama was unable to distinguish between [Vali] and the monkey king Sugriva … when the twin brothers were fighting hand to hand” (p. 36 n. 32). This is an enticing suggestion, and indeed the episode is paraphrased in a collection of Buddhist jataka tales translated into Chinese in the third-century,  showing that the story existed in China for centuries prior to the publication of the standard 1592 edition of Journey to the West. However, I should point out that the tale doesn’t mention the pugilistic primates being identical. In fact, they’re not even brothers. It simply reads,
The following day the monkey fought with his uncle. The [human] king bent the bow and took out arrows … Though far off, the uncle shuddered with horror. He was mighty afraid. He wandered about [a while] and ran away (Mair, 1989, p. 677).
明日猴與舅戰，王乃彎弓擩矢 … 舅遙悚懼，播徊迸馳
That’s not to say the author-compiler of Journey to the West wasn’t influenced by the tale and independently came upon the idea of twin monkeys. It’s just that I think there are other avenues open to research.
Fig. 3 – The Great Sage and his impostor battle in the Western Paradise (larger version). Artist unknown.
In Chapter 58, the Buddha gives his congregation a sermon on nonduality (Sk: advaya; Ch: bu’er, 不二), discussing existence and nonexistence, form and formlessness, and emptiness and nonemptiness. Just as the battle between Monkey and his double erupts on Spirit Vulture Mountain (fig. 3), the Enlightened One tells his congregation: “You are all of one mind, but take a look at two Minds in competition and strife arriving here” (Wu & Yu, 2012, vol. 3, p. 113). “One mind” (Sk: ekacitta; Ch: yixin, 一心) is a high-level philosophy and core tenet of many Buddhist schools that refers to a tranquil, immovable mind that encompasses nonduality (Buswell & Lopez, 2014, pp. 1031-1032; Huang, 2005, p. 68). “Two minds” (erxin, 二心) refers to the dichotomy of the “true mind” (zhenxin, 眞/真心), “the original, simple, pure, natural mind of all creatures, [or] the Buddha-mind” and the “illusionary mind” (wangxin, 妄心), “which results in complexity and confusion” (Soothill and Hodous, 1937/2006, pp. 24-25). A poem in chapter 58 specifically associates two minds with confusion. The first two lines read: “If one has two minds, disasters he’ll breed; / He’ll guess and conjecture both far and near” (Wu & Yu, 2012, vol. 3, p. 113).
It’s important to remember that Wukong is an embodiment of the “Mind Monkey” (xinyuan, 心猿), a Buddho-Daoist concept denoting the disquieted thoughts that keep man trapped in Samsara.  As his double, the Six-Eared Macaque is also a Mind Monkey. Therefore, I suggest that the battle between these twin primates is an allegory for the struggle between the true and illusionary minds within our hero. After all, Wukong is the true Monkey, while his double, the fake Monkey, lives under the fantasy that he can take the Great Sage’s place and finish the quest on his own. Furthermore, given chapter 58’s emphasis on nonduality, I argue Monkey killing the Six-Eared Macaque in the end represents the blossoming of one mind/true mind by extinguishing the illusionary mind. This fits with Sun’s (2018) suggestion that the killing “is an action of eliminating the monster in him [Wukong], indicating that he is getting closer to achieving Buddhahood at this point in the journey” (p. 25). 
4. Appearance in other literature
The Six-Eared Macaque is mentioned by name twice and referenced once in A Supplement to the Journey to the West (Xiyoubu, 西遊補, c. 1640), a 16-chapter sequel and addendum to the original novel taking place between the end of chapter 61 and the beginning of chapter 62. In the story, Monkey is trapped in a dream world where he wanders from one disjointed adventure to the next searching for a magic weapon needed to clear the pilgrims’ path to India. In chapter ten, he attempts to leave a magic tower of mirrors and becomes hopelessly entangled in a net of sentient red threads that adapt to any transformation he uses to escape. An elderly man claiming to be Sun Wukong, the Great Sage Equaling Heaven, comes to his rescue by snapping the threads for him. But upon hearing the man’s name, Monkey lashes out at him with his weapon, exclaiming: “You rascally six-eared ape! Have you come to trick me again? Take a look at my cudgel!” (Dong, Lin, & Schulz, 2000, p. 87). But after the old man vanishes in a flash, Wukong realizes that he was saved by his very own spirit.
In chapter 12, a blind court singer plays a tune recounting events from the original novel for the enjoyment of Tripitaka and a foreign king. A section of the song goes: “A pair of Sage Monkeys deceived Guanyin” (Dong, Lin, & Schulz, 2000, p. 104). 
In chapter 15, after giving up the quest and becoming a commander for the foreign king, Tripitaka starts amassing an army. Sun Wukong is listed among the generals, but because Monkey is investigating his master’s change of heart, he instead presents himself as his brother, the Six-Eared Macaque:
The name “Great General Sun Wukong” was called. The Tang Priest blanched and gazed below his platform. It happened that Monkey had mixed amongst the army for the past three days in the form of a six-eared monkey soldier. When he heard the three words “Sun Wukong” he leaped out of formation and knelt on the ground, saying, “Little General Sun Wukong is transporting supplies and couldn’t be present. I’m his brother Sun Wuhuan [孫悟幻, “Monkey Awakened to Fantasy”] , and I wish to take his place in battle. In this I dare disobey the Commander’s order.”
The Tang Priest said, “Sun Wuhuan, what is your origin? Tell me quickly, and I’ll spare your life.”
Hopping and dancing, Monkey said:
In the old days I was a monster,
Who took the name of Monkey.
After the Great Sage left the Tang Priest,
I became his close relation by way of marriage.
There’s no need to ask my name,
I’m the Six-eared Monkey, Great General Sun Wuhuan.
The Tang Priest said, “The six-eared ape used to be Monkey’s enemy. Now he’s forgotten the old grudge and become generous. He must be a good man.” He ordered [the minor general] White Banner to give Sun Wuhuan a suit of the iron armor of the vanguard and appointed him “Vanguard General to Destroy Entrenchment” (Dong, Lin, & Schulz, 2000, p. 122).
5. Black Myth: Wukong
Black Myth: Wukong (Hei shenhua: Wukong, 黑神話：悟空, Summer of 2024) is an upcoming action RPG by the independent Chinese developer Game Science (Youxi Kexue, 遊戲科學). A trailer with 13 minutes of gameplay was released August 20th of 2020 and (as of 11-4-20) has garnered over 6.7 million views on YouTube alone (video 1). It opens on an aged, furry and squint-faced, long-nailed monk (likely Wukong) sitting in a rundown temple and recalling assorted legends about Monkey. One says the hero became a Buddha and stayed on Spirit Mountain; another that he died on the journey and a different figure was given buddhahood in his place; and another still that Wukong is just a fictional character from a story. The monk then tells the viewer, “But you must not have heard the story I’m going to tell,” thus alluding to the unofficial or “black myth” (hei shenhua, 黑神話).
The trailer features a gorgeous, immersive world in which Wukong travels by foot, wing, and cloud battling underlings and demonic bosses. Monkey is shown capable of freezing enemies in place, making soldiers with his hair, and hardening his body to avoid damage, as well as transforming into a cicada (for covert travel and reconnaissance) and a large golden ape (for boss battles). See here for a great explanation of the cultural and literary references in the game.
Video 1 – The 13 minute game play trailer for Black Myth: Wukong.
Interestingly, some characters in the game hint at a second Wukong. For example, a low-level demon boss says, “Hmm…another monkey?” upon meeting Wukong. Later, an earth god sees him and proclaims, “Similar!”, thus alluding to the other Monkey. This mystery comes to a head at the end of the trailer when Wukong goes to strike another character, and his weapon is blocked by a staff with little effort. The camera pans upwards along the shaft, passed glowing Chinese characters for the “‘As-you-will’ Gold-Banded Staff” (Ruyi jingu bang, 如意金箍棒), revealing the Great Sage Equaling Heaven in his golden armor. This implies the “real” Sun Wukong has arrived and the gamer has been playing as a “fake” Monkey the entire time. But who is this figure?
I suggest this fake Monkey is the Six-Eared Macaque. As noted above, this impostor wishes to win all the glory by completing the quest on his own. His exact words read:
I struck the Tang Monk [with my staff] and I took the luggage not because I didn’t want to go to the West, nor because I loved to live in this place [Flower-Fruit Mountain]. I’m studying the rescript at the moment precisely because I want to go to the West all by myself to ask Buddha for the scriptures. When I deliver them to the Land of the East, it will be my success and no one else’s. Those people of the South Jambudvipa Continent will honor me then as their patriarch and my fame will last for all posterity (Wu & Yu, 2012, vol. 3, p. 100).
This would explain why the fake Monkey is traveling alone and why the real Wukong stops him at the end of the trailer.
The Six-Eared Macaque is a supernatural primate who wishes to take Wukong’s place in order to win all the glory by finishing the quest on his own. He is possibly Monkey’s former sworn brother, the Macaque King, who took the title “Great Sage Informing Wind.” His six ears are likely based on the Buddhist phrase “The dharma is not to be transmitted to the sixth ear,” denoting a great secret that must only be passed to an initiated disciple. His ability to eavesdrop on such secrets from a thousand miles away identifies him as a practitioner of heterodoxy. Being a copy of Monkey, the macaque also symbolizes the “Mind Monkey,” thereby marking their battle as an allegory for the internal struggle between the true and illusionary minds. The spirit’s death at the end represents the blossoming of One Mind.
The Six-Eared Macaque is referenced several times in the sequel A Supplement to the Journey to the West (1640). In chapter ten, Monkey is freed from a magical trap by his very own spirit, who presents himself as Sun Wukong, causing our hero to mistakenly assume his doppelganger has returned. In chapter 12, a court singer alludes to Guanyin’s failure to distinguish the true Great Sage from the fake one. Finally, in chapter 15, Wukong presents himself as the macaque in order to infiltrate Tripitaka’s army.
The spirit is likely the main character of the upcoming action RPG Black Myth: Wukong (2024). The trailer shows this Monkey fighting all manner of underlings and bosses along his solo quest. But the “real” Wukong appears at the end to cross staves, thus showing the gamer is playing as the impostor.
A friend recently asked me an interesting question: “Do you think that the Six-Eared Macaque has Sun Wukong’s fire eyes and golden pupils [huoyan jinjing, 火眼金睛]?” My initial thought was “no” since he was never subjected to Laozi’s furnace, but then I remembered that chapter 58 reads:
His looks were exactly the same as those of the Great Sage: he, too, had a golden headband clamped to his blondish-brown hair, a pair of fiery eyes with golden irises (emphasis added), a monk’s robe on his body, a tiger kilt tied around his waist, a gold-banded iron staff in one of his hands, and a pair of deerskin boots on his feet (based on Wu & Yu, 2012, vol. 3, p. 104).
The original article above already establishes that Six Ears is a manifestation of Monkey’s mind. It’s only natural then that he too would have the same appearance and carry the same scars. But this raises the question: When did the two split? As pointed out above, one scholar suggests that Six Ears was once Sun’s sworn brother, the Macaque King (Mihou wang, 獼猴王). If true, this would suggest that they split prior to Monkey’s turn in the furnace. This makes sense as an early split would allow Six Ears to gain the same magic powers at a similar pace.
But an early split carries with it a certain implication: Six Ears would have experienced the tortuous heat and smoke of Laozi’s furnace while physically separated from Sun Wukong. It would be like the two were connected by an invisible link, similar to entangled particles in Quantum physics (fig. 4).
Can you imagine it? The sheer terror of your super ears hearing that your counterpart is about to be shoved into a celestial furnace, and then the feeling of torturous heat and smoke assaulting your body and eyes (fig. 5). Perhaps Six Ears would try rushing to heaven to stop this but is overcome by the pain affecting him…for 49 days (or 49 years depending on his location). 
Fig. 11 (top) – An artist’s interpretation of Quantum entanglement (larger version). Image found here. Fig. 12 (bottom) – A stunt performer running around on fire. I imagine something similar would happen to Six Ears once Monkey is pushed into Laozi’s furnace (larger version). Image found here.
And it just occurred to me while writing that Six Ears would have also been subject to imprisonment under Five Elements Mountain (Wuxing shan, 五行山). I’ll let you decide if he is weighed down by an invisible, metaphysical mountain or a physical object (see the paragraph above figure 2 here for one possibility).
The Quantum physics-like entanglement shared by the twin monkeys also explains why Six Ears has a golden headband (refer back to the quote above). They are after all two sides to the same person. Most importantly, the novel establishes that the tight-fillet spell also causes the doppelganger pain (Wu & Yu, 2012, vol. 3, p. 106, for example).
Both Six Ears and (at least some of) the monkeys on the Mountain of Flowers and Fruit are depicted as cannibals. This happens in chapter 57:
When that Pilgrim [a magically disguised Six Ears] saw that the Sha Monk had been forced to flee, he did not give chase. He went back to his cave instead and told his little ones to have the dead monkey skinned. Then his meat was taken to be fried and served as food along with coconut and grape wines (Wu & Yu, 2012, vol. 3, p. 101).
那行者 … 把沙和尚逼得走了，他也不來追趕。回洞教小的們把打死的妖屍拖在一邊，剝了皮，取肉煎炒，將椰子酒、葡萄酒，同群猴都吃了。
It just occurred to me that since Six Ears is an aspect of Sun Wukong’s mind, the other two celestial primates could be as well. All three being aspects of Sun’s mind would thus explain why they “are not classified in the ten categories [of life], nor are they contained in the names between Heaven and Earth” (Wu & Yu, 2012, vol. 3, p. 115). They aren’t classified because they were never born. They are simply personifications of Sun’s base and noble qualities. How and when they would have splintered from his psyche is the big question.
I doubt I’m the first person to think of this. I’m interested to hear what my readers think.
Above, I showed how the mentions of “one mind” and “two minds” (and the corresponding “true and illusionary minds”) prove that Six Ears is an aspect of Sun Wukong’s mind, a personification of our hero’s baser qualities if you will. But I want to remind the reader that other features of chapter 58 support this fact:
- The Bodhisattva Guanyin and her “eyes of wisdom” (huiyan, 慧眼) can’t tell them apart:
The various deities and the Bodhisattva stared at the two for a long time, but none could tell them apart (Wu & Yu, 2012, vol. 3, p. 106).
Pressing his palms together, our Buddha said, “Guanyin, the Honored One, can you tell which is the true Pilgrim and which is the false one?” “They came to your disciple’s humble region the other day,” replied the Bodhisattva, “but I truly could not distinguish between them …” (Wu & Yu, 2012, vol. 3, p. 114).
- The tight-fillet spell works on both Monkeys:
Asking Moksa and Goodly Wealth [a.k.a. Red Boy] to approach her, the Bodhisattva whispered to them this instruction: “Each of you take hold of one of them firmly, and let me start reciting in secret the Tight-Fillet Spell. The one whose head hurts is the real monkey; the one who has no pain is specious.” Indeed, the two disciples took hold of the two Pilgrims as the Bodhisattva recited in silence the magic words. At once the two of them gripped their heads and rolled on the ground, both screaming, “Don’t recite! Don’t recite!” The Bodhisattva stopped her recital … (Wu & Yu, 2012, vol. 3, p. 106).
- Both the Jade Emperor and the imp-reflecting mirror can’t tell them apart:
Issuing a decree at once to summon Devariija Li, the Pagoda-Bearer, the Jade Emperor commanded: “Let us look at those two fellows through the imp-reflecting mirror, so that the false may perish and the true endure.” The devariija took out the mirror immediately and asked the Jade Emperor to watch with the various celestial deities. What appeared in the mirror were two reflections of Sun Wukong: there was not the slightest difference between their golden fillets, their clothing, and even their hair. Since the Jade Emperor found it impossible to distinguish them, he ordered them chased out of the hall (Wu & Yu, 2012, vol. 3, pp. 107-108).
- Only omniscient beings like Investigative Hearing and the Buddha can tell the two apart:
[T]he Bodhisattva Ksitigarbha said, “Wait a moment! Wait a moment! Let me ask Investigative Hearing to listen for you.” That Investigative Hearing, you see, happens to be a beast that usually lies beneath the desk of Ksitigarbha. When he crouches on the ground, he can in an instant perceive the true and the false, the virtuous and the wicked among all short-haired creatures, scaly creatures, hairy creatures, winged creatures, and crawling creatures, and among all the celestial immortals, the earthly immortals, the divine immortals, the human immortals, and the spirit immortals resident in all the cave Heavens and blessed lands in the various shrines, rivers, and mountains of the Four Great Continents. In obedience, therefore, to the command of Ksitigarbha, the beast prostrated himself in the courtyard of the Hall of Darkness, and in a little while, he raised his head to say to his master, “I have the name of the fiend …” (Wu & Yu, 2012, vol. 3, p. 112).
Smiling, Tathagata said, “Though all of you [Guanyin] possess vast dharma power and are able to observe the events of the whole universe, you cannot know all the things therein, nor do you have the knowledge of all the species” (Wu & Yu, 2012, vol. 3, p. 114).
[After the Buddha explains the ten categories of life and the four types of celestial primates (see the introduction here), he says:]
As I see the matter, that specious Wukong must be a six-eared macaque … (Wu & Yu, 2012, vol. 3, p. 115).
In short, the twin monkeys are so hard to tell apart simply because they are representations of the true and illusionary minds within the same person.
Six Ears displays one of several powers possessed by Buddhist sages. Volume five, part 51 of the Saṃyutta Nikāya (Sk: संयुक्त निकाया; Ch: Xiang ying bu, 相應部, c. 250 BCE) explains:
When the four bases for spiritual power have been developed and cultivated in this way, a bhikkhu, with the divine ear element, which is purified and surpasses the human, hears both kinds of sounds, the divine and human, those that are far as well as near (Bodhi, 2000, p. 1727).
The end of chapter 58 sees the Buddha trap Six Ears under his alms bowl:
The [Six-Eared] macaque’s hair stood on end, for he supposed that he would not be able to escape. Shaking his body quickly, he changed at once into a bee, flying straight up. Tathagata threw up into the air a golden almsbowl [jin boyu, 金缽盂], which caught the bee and brought it down [figs. 13 & 14]. Not perceiving that, the congregation thought the macaque had escaped. With a smile, Tathagata said, “Be silent, all of you. The monster-spirit hasn’t escaped. He’s underneath this alms bowl of mine” (Wu & Yu, 2012, vol. 3, p. 116).
Fig. 13 – A detail of Six Ears under the Buddha’s alms bowl (larger version). The true Sun Wukong stands to the right. Fig. 14 – The full print (larger version). From the original 1592 edition of JTTW.
This is similar to how the Buddha captures Red Boy (Honghai’er, 紅孩兒; a.k.a. Ainu’er, 愛奴兒) in the early-Ming Journey to the West zaju play (Xiyou ji zaju, 西遊記雜劇), which predates the standard 1592 edition of the novel. It’s important to note that the play casts him as the son of the yakshini Hariti instead of Princess Iron Fan. 
This is based on a common story cycle from Buddhist canon in which the Enlightened one hides the demoness’ youngest son in his alms bowl in an attempt to stop her from eating human children. For instance, the Samyuktavastu (Ch: Genbenshuo yiqie youbu binaye zashi, 根本說一切有部毘奈耶雜事; T24, no. 1451) states that he hides the boy under the bowl like Six Ears:
The next day at first light, the Buddha having taken his robe and his bowl, entered into the city in order to seek his food. Having begged following the order of the houses, he came back to the place where he lived and took his meal; after which he went to the residence of the yaksini Hariti [Helidi, 訶利底]. At that moment, the yaksini had gone out and was not at her home but the smallest of her sons, Priyankara [Ai’er, 愛兒] remained at the house. The Bhagavat concealed him under his almsbowl [bo, 鉢] and because of his power (as a) Tathagatha the older brothers could not see their youngest brother and the youngest brother could not see the older ones (Rowan, 2002, p. 142). 
(Yes, the name Ai’er likely influenced Red Boy’s name Ainu’er from the early-Ming zaju play)
The Scripture on the Storehouse of Sundry Treasures (Za baozang jing, 雜寶藏經; T4, no. 203, mid-5th-century CE) says that he hides the boy at the bottom. This version is not long, so I will transcribe it in full:
Hariti [Ch: Guizimu, 鬼子母; lit: “Mother of Ghosts”] was the wife of the demon king Pancika. She had ten thousand sons who all had the strength of fine athletes. The youngest one was called Pingala [Binjialuo, 嬪伽羅]. This demon mother was inhuman and cruel. She killed people’s sons to eat them. People suffered because of her. They appealed to the World-honored One. The World-honored One then took her son Pingala and put him at the bottom of his bowl [bo, 鉢]. Hariti looked everywhere in the world for him for seven days, but she did not find him. She was sorrowful and sad. When she heard others say, “It is said that the Buddha, the World-honored One, is omniscient,” she went to the Buddha and asked him where her son was.
The Buddha then answered, “You have ten thousand sons. You have lost only one son. Why do you search for him, suffering and sad? People in the world may have one son, or they may have several sons, but you kill them.’’ Hariti said to the Buddha, “If I can find Pingala now, I shall never kill anyone’s son any more.” So the Buddha let Hariti see Pingala in his bowl. She exerted her supernatural strength, but she could not pull him out. She implored the Buddha, and the Buddha said, “If you can accept the three refuges and the five precepts now, and never in your life kill any more, I shall return your son.” Hariti did as the Buddha told her to, and she accepted the three refuges and the five precepts. After she had accepted them, he returned her son.
The Buddha said, “Keep the precepts well! In the time of Buddha Kasyapa you were the seventh, the youngest daughter of King Jieni. You performed acts of great merit, but because you did not keep the precepts you have received the body of a demon” (based on Tanyao, Kikkaya, & Liu, 1994, pp. 220-221).
Hariti’s inability to free the child was later exaggerated in a detail from a mid-Qing dynasty hell scroll. It depicts a host of demons using a makeshift wooden pulley to no avail (figs. 15 & 16).
Fig. 15 – A detail of the demon horde trying to free Pingala (larger version). Fig. 16 – A detail of the detail (larger version). I love the transparent bowl. Images from the Maidstone Museum.
The immovable quality of the Buddha’s alms bowl (or anything inside like Six Ears and Red Boy) is likely related to a story told by the pilgrim Faxian (法顯, 337 – c. 422 CE):
Buddha’s alms-bowl [bo, 缽] is in this country [of Peshawar]. Formerly, a king of Yuezhi raised a large force and invaded this country, wishing to carry the [Buddha’s] bowl away. Having subdued the kingdom, as he and his captains were sincere believers in the Law of Buddha, and wished to carry off the bowl, they proceeded to present their offerings on a great scale. When they had done so to the Three Treasures, he made a large elephant be grandly caparisoned, and placed the bowl upon it. But the elephant knelt down on the ground, and was unable to go forward. Again he caused a four-wheeled wagon to be prepared in which the bowl was put to be conveyed away. Eight elephants were then yoked to it, and dragged it with their united strength; but neither were they able to go forward. The king knew that the time for an association between himself and the bowl had not yet arrived, and was sad and deeply ashamed of himself. Forthwith he built a tope at the place and a monastery, and left a guard to watch (the bowl), making all sorts of contributions (based on Faxian & Legge, 1886/1965, pp. 34-35).
The Buddha using his alms bowl to trap spirits like Six Ears finds a parallel in Babylonian Demon Bowls (fig. 17). Bohak (1996) explains:
Those bowls which are found in situ often are positioned face-down, and in some cases two bowls are found glued together with pitch, the space enclosed between them containing such items as inscribed egg-shells or human skull fragments. From their positioning, and from the images of bound demons which adorn numerous bowls, it would seem that these were demon traps, meant to lure, trap, and disable any malevolent demons, preventing them from hurting humans or causing damage to property. It seems that such traps often were placed in room corners, since the meeting of walls and floor created cracks through which the demons could sneak in — a fact which is also verified in contemporary literary sources.
Fig. 17 – A circa 400 to 800 CE demon bowl written with Babylonian Aramaic (larger version). Image found here. See this page for several examples.
1) The travel rescript is like an imperial passport that needs to be stamped by each kingdom to guarantee legal passage along the quest to India. It contains an introductory letter from the Tang emperor and the stamps of all the kingdoms already visited.
2) The imp-reflecting mirror is used in chapter six to see through Monkey’s various magical disguises during his battle with Erlang (Wu, & Yu, 2012, vol. 1, pp. 179 and 184).
3) This is comparing a monkey’s prognathic face with the beak of the Chinese thunder god, who is commonly portrayed as a bird man.
4. Saturn (Tuxing, 土星; lit: “Earth Star”) is mentioned here because the stellar deity is known for having a thickly-bearded face (see figure one on this article). The reference is saying that Sun Wukong’s sunken cheeks are hairless.
5) Yu (Wu, & Yu, 2012) translates the name as “acquiescent staff of iron” (vol. 3, p. 105). My thanks to Irwen Wong for suggesting the alternative translation.
6) Wukong takes his six sworn brothers in chapter three shortly after establishing his monkey tribe as a military power. The other brothers include the Bull Monster King, the Dragon Monster King, the Garuda Monster King, the Giant Lynx King, and the Orangutan King (Wu, & Yu, 2012, vol. 1, pp. 138-139).
7) Yu (Wu, & Yu, 2012) translates the name as “Telltale Great Sage” (vol. 1, p. 157).
8) For example, Monkey sees through the White Bone Spirit‘s disguises in chapter 27 (Wu & Yu, 2012, vol. 2, pp. 19-20).
9) For example, after he successfully meets a goat spirit’s challenge to boil in oil, Wukong discovers the liquid is somehow cool to the touch during the animal’s turn. Monkey then summons a dragon king who tells him:
[T]his cursed beast did go through quite an austere process of self-cultivation, to the point where he was able to cast off his original shell. He has acquired the true magic of the Five Thunders, while the rest of the magic powers he has are all those developed by heterodoxy, none fit to lead him to the true way of the immortals (Wu, & Yu, 2012, vol. 2, p. 313).
10) The Dasaratha Jataka is story no. 46 in The Collection of Sutras on the Six Paramitas (Liudu jijing, 六度集經, third-century) (CBETA, 2016), a compilation of karmic merit tales (Sk: avadana) translated into Chinese by the Sogdian Buddhist monk Kang Senghui (康僧會, d. 280). See Mair, 1989, pp. 676-678 for a full English translation.
11) Examples of the term’s use include titles for chapters seven (“From the Eight Trigrams Brazier the Great Sage escapes; / Beneath the Five Phases Mountain, Mind Monkey is still”) and fourteen (“Mind Monkey returns to the Right; / The Six Robbers vanish from sight”).
12) Alternatively, Sun (2018) suggests: “[H]e kills the six-eared macaque because the latter has copied him too closely, the best demon among the ones that Monkey has conquered” (p. 25).
13) I changed the Wade-Giles to Pinyin. All other quotes from this source will be thus changed.
14) The novel establishes that “one day in heaven is equal to one year on Earth” (Wu & Yu, 2012, vol. 1, pp. 150 and 167).
15) I plan to write an article on this at a later date. I don’t want to take up too much space here.
16) The full English version is based on the Chinese to French translation in Peri, 1917, pp. 3-14.
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