If don Juan has taught me anything, it's that power plants can be used to shake you around a little and open your eyes to the bigger picture. But the path to knowledge or enlightenment can be traversed without them.
I see no major harm in the safe use of psychedelics, and yes I do believe there is a safe way to use psychedelics.
Beauty is in the eye of the beholder, but the trip is in the mind of the tripper.
If you think you're going to have a bad trip, you're setting yourself up to have a bad trip. Like most psychoactive substances, your predisposition can play a MAJOR role in the effect of the substance.
I say, experiment safely. And the best way to experiment more safely: Knowledge. Here is a site dedicated to educating people on the subject matter of psychoactive drugs, from plants to herbs to chemicals to inhalents, this site LITERALLY has it all.
http://www.erowid.org