Being a science fiction fannut, I think I know what you are talking about. There have been science fiction novels, movies, and shows that have tackled this very concept.
For example, in stargate sg-1 series, there was an episode (season 3 I think) where an alternate version of one of the main characters came through a "quantum mirror" from an earth ravaged by an alien invasion. According to the alternate main character, in the first day of the invasion alone, bombardment from orbit killed an estimated 1.5 billion people. In the days after, people were systematically put in chains to be shipped off into slavery by the aliens. Obviously, the main characters of this "quantum reality" found a way many months ago to protect earth from such a fate. As one of the characters described the situation, "What did we have that they didn't? Our fate." We, as the viewers, knew that the main characters of this show knew a way to save the alternate earth and the alternate population.
Obviously, any viewer who has a conscience should think that the main characters ought to have helped save the alternate earth and its people, but they decided not to. They all agreed that whatever the hell happened in the alternate reality had absolutely no consequence whatsoever on their world. Dr. Jackson turned out to be the only person that pointed out that he felt a kind of cosmic responsibility to at least lift a finger to help these billions of people who were being killed and enslaved.
I think Rob fears that if indeed there are alternate universes that we would not feel any moral obligation toward the other universes because ultimately nothing that happens in the other universes would have any consequence on this one.
I just want Rob to know that not all of us feel that way, and I think that was what the story writers of that particular episode intended. While almost all the main characters in that episode felt absolutely nothing (no sorrow, no sympathy, nada, nothing) for the billions of humans in the alternate universe who were being killed and enslaved, one character spoke up and professed that he felt a kind of universal moral obligation to at least do something to help save the remaining humans in that universe.
Anyway, my personal opinion at least... this is the only point Rob ever raised that made any sense.
Now, I would also like to point out that whether we "like" an idea or not out of personal beliefs has absolutely no bearing on whether the idea is true or not. I've said this before and I'm going to say it again. Yellow is my favorite color. I'd like the idea that the sky is yellow. But obviously the sky is blue during the day, orangish-reddish in the evening, and black during the night. No amount of my dislike for the colors blue, red, and black or amount of my positive attitude toward the color yellow is going to make the sky yellow.
In the same token, whether there is a universal morality that applies to all the quantum universes or not has absolutely no bearing on whether these universes actually exist or not.
Added by edit.
By the way, in the end, the person in charge ordered the quantum mirror destroyed, permanently disconnecting their reality from the rest of alternate universe, implying that the other characters indeed did feel some kind of sorrow or sympathy for the victims in the other universe but would rather not face the enormous responsibility. It's like changing the channel everytime one of those commercials that show victims of extreme poverty turned up.
Edited by Tazmanian Devil, : No reason given.
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He, him, and his are not intended as exclusively masculine pronouns. They may refer to either sex or to both sexes!
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