If one understands himself, there can be no harmful effects in using it. Marijuana doesn't make me do anything that I wouldn't be capable of doing otherwise. I find it far more pleasant than drinking, less messy and more private. I never had the patience to sit in a bar and drink. Having a joint is far more economical and more immediate. I'm able to switch into certain inner places with marijuana. I've also taken a couple of trips that have been incredible. - Elliot Gould