I am not sure I agree with this statement, but it makes one wonder what the relationship between schizophrenia, insanity, and enlightenment are. Within the same spectrum, is it possible for people to go crazy while seeking enlightenment, even if they never reach higher states of consciousness?
What about fear that becoming enlightened will make one go crazy? Is this a defense mechanism of the ego when faced with the possibility of its destruction? I myself have had moments where I feel like I am on the verge of some sort of breakthrough after meditating or contemplating on the common spiritual inquiry of "Who am I?", which of course is used as a hua-tou/hwadu in the Zen tradition, but then suddenly become gripped with fear. Huang Po describes the situation I believe:
Men are afraid to forget their minds, fearing to fall through the Void with nothing to stay their fall. They do not know that the Void is not really void, but the realm of the real Dharma.
Similar notions exist in other mystical traditions, such as the Christian notion of the "dark night of the soul." How is this related to insanity and is there any danger of falling into insanity when facing dilemmas like this on the path? How can one overcome such fears and "take the plunge" as it were? (Just to note, I have no mental illnesses, this is just a fear that occasionally manifests during the experiences I just spoke of.)
Finally, is there any traditional literature by Buddhist masters or even scripture which touches upon these issues that anyone knows of?