I've learned from all the different psychedelics I've come across, but I must say it's the dear ol' psiloscybe shrooms as well as my friend 2C-E which have been most valuable for opposite reasons. With mushrooms, it tends to be an incredibly emotional and almost explosive experience where things from the shadow regions of the psyche come to the surface...things I didn't even know were there. And with 2C-E, it's a very emotionally neutral and removed trip, which allows a look at the self without the emotional defenses, it's almost an objective perspective of the mind. Both of these substances are incredibly complex, and there is much more I could go into....but I won't!