首楞嚴義疏注經 4.275

4.275

狂故怖頭，因緣何有？頭無得失，狂自復行，惑性妄有滅生，真性何曾出沒？汝觀如狂之妄，今指何處為因？

Being mad, he was terrified about his head; how could there be causes and conditions? His head had neither gain nor loss; the madness just ran on by itself. The nature of affliction falsely has cessation and arising, but when has the true nature ever appeared or disappeared? As you observe delusion which is like madness, what place can you now point to as its cause?