So, this entire post is based on me miss-reading a YouTube comment. I thought the commenter said (I'm paraphrasing) that it would be interesting if people were to write fantasy stories in a setting where morality was different. He or she then followed with an example that was not a different moral reality- it was a different perception of morality.
When I went back and re-read the comment, I discovered that the person had never been talking about inventing worlds where morality was different- they simply thought it would be interesting if people spent more time detailing what moral beliefs people (or creatures) followed in an invented world.
Of course, by then I had several pages, written long-hand (at 3:00 AM) detailing the difference between alternate morality and an altered perception of reality.
There are very few stories in a setting which involves an actual different morality. The one that comes to mind is Perelandra by C. S. Lewis. The concept behind the story is `what if someone from our world went to a planet where sin was never introduced, and they had a chance to warn the Eve figure against disobeying God?'
The people on Perelandra are naked, and there's nothing wrong with that. Not `there's no man-made stigma against it' but literally nothing wrong with it. The main character, Ransom, can talk all day to a naked woman and not have even a twinge of lust or embarrassment -not even think of her as naked- because everyone on Perelandra is operating under a different moral system than that of earth.
What is immoral on Perelandra is spending the night on solid ground. All the land is floating, the landscape constantly changing with the swells and dips of the ocean waves forming mountains and valleys -all except one tiny rock island, which the people were warned by God not to inhabit. Doing so (Ransom eventually realizes) doesn't just show disobedience, but also a lack of faith -a desire to take control away from God by seeking an earthly permanence.
Now, C. S. Lewis was a Christian apologist (that's not someone who apologies for being a Christian; a Christian apologist is basically a philosopher who starts out with the underlying assumption that Christianity is true and that all his philosophies must build off that foundation.) so he was deeply interested in the underlying philosophy behind what is and isn't immoral. Maybe that's why he was able to write a convincing story about a place where nakedness is find, but if you linger on a rock island as sunset approaches, you will feel rightfully guilty for pushing the line. Perelandra is a thought experiment.
It's really hard to write stories with an actual different morality because certain moral laws are hard-wired into human beings, I believe, by God. This makes actual different moral systems hard to relate to. I'm not sure you can do it without changing physical laws as well.
Coming up with different moral beliefs for different societies, on the other hand, is much easier and makes your world more realistic. It happens in the real world all the time.
For example, according to Jim Bishop's book, The Day Christ Died, `In Rome, the people thought that they were being lenient in permitting condemned men or surly slaves to fight for their lives. Their feeling was: "They are to die anyway. We give them a chance."'
The difference between moral beliefs and actual moral law (the cause/effect of our actions) is the difference between icing and cake. The icing may change how a cake looks, but it doesn't change the cake. Chocolate is still chocolate, yellow cake is still yellow, even if the `icing' is actually whipped cream and strawberries.
Moral beliefs shift all the time, depending on the views of society, and particularly who holds power, but the underlying moral laws do not shift. An example is the chattel slavery in the American south. Treating people as animals was not moral during the time that slavery was legal, and didn't become immoral the second the Emancipation Proclamation was signed.
As a pro-lifer, I would argue that the same principle holds in regard to abortion. I believe a baby is already a baby within the womb, and that calling him or her a fetus pre-birth is akin to slave owners calling black people sub-human.
In both cases, because people are hard-wired to want to be moral -to object to killing babies, or treating people as animals- society has to de-humanize the victims in order to make such actions socially acceptable.
It bothers me that people equate moral laws, given by God, with human laws which shift every time a government changes administration. I am especially concerned for the word-smiths of our nation, that we not confuse different morality with a different perception of morality. It is, to quote Mark Twain, `the difference between lightening and a lightening bug'.