What I've seen is a LOT of false enlightenment in a certain subculture. Hang out for a few hours with the drugged-out burnouts in Williamsburg, Brooklyn to get a sense of it. There's a certain arrogant, self-congratulatory nihilism in the "hipster" culture, and if it's taken more seriously than it deserves, it leads to some very bad places. Is it the drugs or the casual sex alone? Of course not, because drugs and sex are generally harmless (if not possibly beneficial) in moderation. It's a certain self-centered experience-chasing mindset that, for a variety of reasons, is very attractive to young people whose personalities and ideas haven't yet formed.

If people want to use drugs, then I have no problem with that. Certainly I think these chemicals should be legal and that their possible benefits should be researched. But the false enlightenment that I've seen some people fall into is dangerous. It kills a person's work ethic and leaves that person prey to mental illness. Does everyone who uses drugs fall into this pattern? Obviously, no. Do a lot of people who don't use drugs fall into it anyway? Certainly. I think that drugs make people who are exposed to that mentality and culture a lot more susceptible to falling into it, and that's the primary danger.

For the record, I think drug prohibition (which is immoral and should be ended) makes these drugs a lot more dangerous. A lot of people have to be connected to a depraved culture even to have regular access to these drugs. I've often thought that less dangerous than the chemicals themselves are the sorts of toxic people you can end up surrounding yourself with if you want regular, frequent access, due to the drugs' illegality.

I generally think the "meditation sickness" is more scare than substance, without much evidence for a causative link, but I think it's possible in certain circumstances. For example, I've heard of inexperienced people (i.e. people who've taken one hatha yoga class) going on week-long retreats and having negative experiences (including temporary psychosis and anxiety disorders) but that's not what I'm talking about. That's about as irresponsible as for an overweight person who can barely walk a mile to try out for a marathon.

I think that a lot of "meditation sickness" comes from people who are prodromal of some sort of psychological crisis and (because of their increasingly difficult mental state) become interested in altering their consciousness, and that the psychotic break was not caused by the meditation but would have happened anyway. I can't prove that, but it's been my suspicion for a long time. For those who might argue that meditation is therefore bunk because some people who meditate end up getting frank mental illness anyway, my counterpoint would be that it's foolish to expect that a novice meditator can meditate his way out of a potentially physical mental illness; he needs medical help.

What is very dangerous is when people try to use meditation or yoga in lieu of other well-tested, scientific medical treatment, which some New Age types believe in even though most actual meditators and yogis advise strongly against it. I talked to a very accomplished yoga teacher about using meditation to treat panic disorder (didn't want to use benzos) and he said, "Meditate, but see a doctor and take his advice. You can't meditate your way out of this, right now, any more than a person with heart disease can meditate out of that."