This is a comment I hear often, but thankfully, it's an urban myth.

Hypnosis is nothing else but a very relaxed state of being, a bit like day dreaming, or like those few minutes just before we fall asleep. It is pleasant and comfortable. It is a natural state for most people (unless you are very stressed and never manage to fully relax) and there is nothing mysterious about it.

The potential of hypnosis as a therapeutic tool lies in that it is possible to propose positive, healing suggestions that are taken up by the subconscious mind, without the interference of the nagging, self-deprecating conscious mind. In clinical hypnotherapy practice, the clinician and the client would have previously agreed on what it is the client wishes to change and the new beliefs they would prefer.

Furthermore, because we ultimately want only the best for ourselves, the conscious mind (the watchdog in the background) is still always able to react to any suggestion that may be contrary to the person's principles or desires, so that if anything along those lines were suggested, the client would instantly come out of hypnosis.

But...what about that guy you saw barking at a show? Well, guess what? That person was there to have a good time and wanted to play along with the hypnotist's suggestions...If you have ever been to a hypnosis show, you would have noticed that the hypnotist asks first for volunteers, and then chooses amongst those the person who is most responsive to his initial suggestions. So, in truth, the guy who barked on stage was more than happy to take up the suggestion of turning canine for a good laugh to start with!