首楞嚴義疏注經 8.476

8.476

即見習為因也。執見異生，各自明悟，出生相返，發於違拒。及招鬼道，遇精明處以為其形，即日月精魄、山澤明靈有精耀者以託其質。言魍魎者，水石變怪也。

This is caused by the habit of dogmatic views. Tenaciously holding disparate views, each asserting their own discerning realization, producing contrary appearances and expressing defiance and rejection. When incurring the ghost destiny, they encounter quintessential brightness to take their shape—that is, the essences of the sun and moon, or the luminous spirits of mountains and marshes that possess gleaming brilliance, are what they rely upon for their substance. Those called specters (wǎngliǎng) are anomalous transformations of waters and rocks.