I used to smoke a lot when I was younger (16 to 22), then quit. Now I am 36 and have started smoking again, this time using a vaporiser which is more gentle to the throat and supposedly less harmful to your lungs. I find cannabis to be quite safe. It's true that it makes some people feel nervous or paranoid, but from my experience these symptoms are probably the result of some sort of autosuggestion rather than caused by the drug itself. Usually I smoke at home when I'm alone, maybe 3 or 4 times a month, and I mostly just talk to myself, trying to be honest and to speak my mind. I reflect on my life, make plans, think of things I'd like to say to certain people. Psychologically I think it's highly beneficial, and I have fun as well. Then again, this is how I use it, other people use it differently, so I'm not trying to be categorical here.