Yes and no. It will ultimately depend on the individual. I was 19 when I became a heavy pot smoker, and I smoked it all day every day for the next six years. In that time, I took an idea I had for a business and turned it into a career that, at its peak, paid me six figures. I've often felt like the stereotype weirdo that people make fun of, but it's true: The weed cleared my mind and gave me legitimate ambition and drive. It wasn't until I got married and stopped smoking that I started to suck ***. I've talked to my shrink about it and she's mentioned that THC works as a substitute for saratonin, which is the goo in your brain that either does or doesn't cause clinical depression. (that is the idiots definition, just go with it) It just so happened that it did wonders for me. I keep telling my wife that we'd both be a lot happier if I could just roast a fatty every once in a while... Frickin' Mormons.