Chimp, you know nothing. The reason all of the people that you know that smoke pot are retarded, was because they were retarded to begin with and that's why the succumbed to using drugs every day. Pot, like all other substances, should be used in moderation (say once or twice a week), merely because they do affect behaviour whilst under the influence. When you are actually high you do become a bit stupid, and you're more interested in snacking and watching comedy than homework. But it's someone's choice, it's not some long term damage caused by pot. It's short term. If your retarded cohort could sober up for a day he'd probably be fine.
"Do you see me arguing for excessive tobacco and alcohol consumption? Even then, tobacco and alcohol destroy your body, not your mind."
Alcohol doesn't destroy your mind!?

Rethink that. As everyone knows, alcohol actually destroys brain-cells, something, I think, pot does not.