The masterpiece Journey to the West by Wu Cheng’en and its animated adaptations have become legendary among many audiences in Asia. However, despite the numerous “plot holes,” there are still many details in this classic that leave many viewers perplexed.
As we know, Sun Wukong possesses extraordinary abilities, allowing him to travel vast distances in mere moments. His speed is unmatched by modern modes of transportation such as high-speed trains or airplanes. In contrast, Tang Seng, the monk in Journey to the West, had to endure a grueling journey that took him nearly 14 years to reach the Western Heaven.

Some viewers might argue: if Sun Wukong can use his abilities, why couldn’t Tang Seng just use his skills to reach the Western Heaven quickly? The truth is that Tang Seng’s journey was not just a matter of speed; it involved overcoming numerous challenges and tests along the way.
In the narrative of Journey to the West, there is a moment when Tang Seng mentions that to reach the Western Heaven, he must be patient and persistent, sometimes even risking his life. He had to endure many trials and tribulations, and only through perseverance could he achieve enlightenment and liberation.
After listening to Tang Seng’s story, Emperor Taizong was quite pleased. He then awarded Tang Seng a travel permit (similar to modern-day travel authorization) to monitor his journey, ensuring that he would not stray from the path. Thus, the extended journey of Tang Seng was not merely due to his lack of speed but also because of the inherent rules governing his quest.

Moreover, the author also weaves in a deeper thematic element through this detail. In the story, Zhu Bajie once remarked after rejecting an offer to cross the Tang River: “If one could fly over the clouds, they would certainly not fall down to the earth. Those who can fly are like mountains.”
The magical ability to fly is indeed reserved for deities, and Tang Seng’s journey reflects this concept. He cannot simply soar through the air like a deity; he must adhere to the spiritual laws that govern his existence. This is the principle of the cosmos; if one is too “light,” they may not be able to remain grounded.
Why is this so? It is because the higher one ascends, the more challenges they face. Zhu Bajie, who transforms into a deity, cannot simply float through the heavens as he pleases. Therefore, despite his desire to quickly reach the Western Heaven, he could not simply fly over the Tang River or arrive at his destination in a straightforward manner.
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