《文心雕龙·论说》
即使抽象的阴阳变化之理，也要说得令人不疑；秘奥的鬼神之道，也同样不能隐避。
阴阳莫忒，鬼神靡遁。
Even abstract principles of yin-yang changes should be articulated in an indubitable way, and mysteries of ghosts and gods should not be hidden.