Zhan Yun considered Ye Lingyun's statement about the Yuwai Great Wall, or rather, Yiye Tian's explanation of it. He wondered how likely it was that this claim was correct.
In fact, Zhan Yun didn't quite believe the claims about the Yuwai Great Wall. He didn't think that the earth's Spiritual Energy came from extraterritorial sources, nor did he believe that there was a source of Spiritual Power outside the realm. He still felt that the gradual depletion of Earth's Spiritual Energy was due to a problem with the world's own laws.
But the problem was that Yiye Tian's claim didn't seem to have any obvious flaws.
Moreover, some of Yiye Tian's explanations matched those of Baili Xuewei, which made Zhan Yun somewhat perplexed and unsure whether to believe Yiye Tian.