[patana]

I admit that I am not going to read the original post, but from a comment: Most basically, because humans are only just on the cusp of general intelligence. I can explain why this is so.

Every time there is a leap from one state to another one, and this latter state is better in the sense that it open new possibilities from transition, then when you get into the new space (the one that this leap open) you realize that the leap was a small one and that there are a lot of leaps to get to the next state (heaven is not one leap away)