Well..i think if there is a limit, we cannot know until we get there... I had the strongest trip of my life, the second tiime i smoked changa...In the middle of it, my ego was so destroyed, that i said to my friend, Endlesness: " I forgot i wasant you"...and at that point all human feelings where strange for me...fear was something to laugh about, aldow, i could only laugh and think about that, maybe one or two minutes after i got to that point. And as i was coming back the only thing i was thinking was: " How can we forget that "I", EGO, and linear time are the biggest ilussions ever!!!" I mean, i felt i was everything, and maybe at the very begingin, when i still had my ego on me, there was a litlle fear an confusion, but soon after "I" was so big an universal, that human feelings was something to small to atack me... When i was coming down, i could still fell this, but i could already fell my ego also..and it was in that point i could talk about time and ego, with no fear, just amazing uinity fellings.