Well, really, its not harmful. Even the smoke. Also another thing i didnt mention is mice subjected to THC lived a significant amount longer than mice not subjected to THC, which shows that THC could prolong life, or in otherwords, protect cells from dying, which ultimatly means you'll live longer.

There's way more pro's to con's.

If cannabis really WAS harmful, someone would have definatly died from it by now, but not one case, ever.

I think thats pretty darn persuasive.