首楞嚴義疏注經 8.528

8.528

因從詐習，鬼為畜魅，類入旁生狐狸所攝。今為人趣，參在佷戾自用之徒，不受諫曉也。

Their cause derived from the habit of deceit: as ghosts they were animal spirits, and categorised among animals they were subsumed under foxes. Now in the human destiny, they mingle with the stubborn, perverse, and self-willed sort who will not accept admonition or clarification.