Obviously if any actions, even a lunatic's, can be causeless, determinism is done for. If the chain of causation can be broken for a madman, it can be broken for a man.
There are three layers to the universe. In the lower, Tai Ching, and the middle, Shan Ching, the hindrance of a physical bodily existence is required. Those who fail to live consistently in accord with the Tao reside here. In the upper, Yu Ching, there is only Tao: the bondage of form is broken, and the only thing existing is the exquisite energy dance of the immortal divine beings.
The Russians will try all the rooms in a house, enter those that are not locked, and when they come to one that cannot be broken into, they will withdraw and invite you to dine genially that same evening.
How strange to have failed as a social creature—even criminals do not fail that way—they are the law's "Loyal Opposition," so to speak. But the insane are always mere guests on earth, eternal strangers carrying around broken decalogues that they cannot read.