The proof is in the people who smoke it, if you have an addictive personality you'll be addicted. But then you're just an idiot. Yes, there is tar in Marijuana, but here are a few facts for you: 1) Most marijuana smokers smoke the bud, not the leaf, of the plant. The bud contains only 33% as much tar as tobacco. 2) Marijuana smokers do not smoke anywhere near as much as tobacco smokers, due to the psychoactive effects of cannabis. (I'm housed after a fat bowl, so I usually am fine for the rest of the day/night. Cigarette smokers aren't 'good' after 1 cigarette, therein lies the problem; chances are also, that i'm not going anywhere except my couch to watch a movie or sleep after that, and its always at the end of the day or after I've finished what I need to do for the day...now that's not to say that other people do it and go function normally....but as far as I'm concerned, if they're functioning then what's the issue?) 3) Not one case of lung cancer has ever been successfully linked to marijuana use. 4) Cannabis, unlike tobacco, does not cause any narrowing of the small air passageways in the lungs Tar is also largely unattributed to cancer, it's the radioactive shit in the cigarettes that are dangerous. Even with all that said, people will retain their viewpoints on it, because its illegal and it has been for a while. If the roles were switched so would the mindsets.