Well seems that simula OOP was a bit more like java/c++.
It was Kay who had the message passing idea, and the smalltalk people still don't consider java/c++/simula-derivatives as true OOP languages because they miss that.
Alan Kay was inspired by the real world, mostly biology back when psychotropic substances were rather popular.
That's were the problems start.
The real world systems are:
1) unpredictable - except for those who can forecast the future.
2) Unreliable
3) Slow
4) Uncoordinated - except if you believe someone runs the world.
5) Unmaintainable - just ask someone on human maintenance (drug research etc).
6) Naturally autonomous
Point 6 is very critical, because in von-neumann architectures you will end up having a shared memory and trying to give an autonomous memory to each agent, will end up very suboptimal, and no zipper, COW of any other FP trick can change that.
You just cannot afford to write your software like the real world, and you don't even have intelligent agents of human ability as building blocks...
http://c2.com/cgi/wiki?AlanKaysDefinitionOfObjectOriented http://userpage.fu-berlin.de/~ram/pub/pub_jf47ht81Ht/doc_kay...