I can't completely agree with this. Sure, cannabis isn't as powerful of an hallucinogen as acid, shrooms, etc, but it has some hallucinogenic effects at higher doses. If you're smoking some really good stuff, you don't even need that much. I've experienced everything being in slow motion after smoking, and even at low doses I can get fractal-like patterns across my whole field of view. So yes, cannabis does have some weak hallucinogenic properties.