The key line, in my opinion (it's late and I really need to sleep, so bare with me), is the line about you not being able to truly understand why or if someone else's cage has any doors or windows from which to escape. If you really think about it, the only truly unique thing in the entire multiverse (if you "believe" modern science, quantum mechanics, M-theory etc.), is a person's or some other being's perspective on that multiverse. Even if we could clone @meno to have two exact copies, even including all memories and experiences, from the moment the clone exists, they both have a different perspective and will from then on develop into their own, unique persons.

While writing this down I'm suddenly thinking about a scene from the sci-fi show Babylon 5. The earthling commander is asked about the many believes on our planet and the alien is very intrigued by this colorful collection of faiths, religions and mythologies. The earthling commander asks the alien about what they believe, how do they explain life, the universe and everything? Her answer stuck with me forever, and I'm paraphrasing here:

We believe that you, commander, are the universe, trying to understand itself.

In my mind I immediately linked that with another quote which I don't remember where it came from:

The Truth is Singular. Therefore any individual perspective on that truth is untrue.

So I can only say what I believe to be true :-) And I believe it to be true that we cannot truly see each other's cages and have no idea if that cage has a door or if that door even has a key to unlock it. We can have our own perspective on someone's cage and that perspective is our own cage. World peace can only be had by learning to better share those perspectives so we can come to some shared truth about our humanity.

Argh... hope that wasn't too confusing. I know I am confused! Thanks again for your eloquence and for poking the brain-muscle once again :-)