Last week, we talked about a pre-industrialized, Polytheistic society. As a society starts to industrialize, it needs to be able to formally educate its people. Through scientific understanding of the world, a society stops believing in things like Gods who drive a sun chariot across the sky and starts relying on science to explain the natural world. There are still things that no amount of technology can control and no amount of science can explain--death and human behavior. So how does society deal with such a gap? This is where Monotheism steps in.
Unlike Polytheism, Monotheism doesn't attempt to explain why the wind blows, the grass grows, and a river flows. It needs only deal with good versus evil behavior and what happens when we die. Interestingly enough, these two are usually related in Monotheistic religions--unlike Polytheistic religions where your after life is usually the same no matter what your moralistic behavior. Monotheistic religions stress rules that govern moral behavior. When a member of a society breaks these rules, they are considered evil and their after life is a reward or consequence of that behavior.
Fantasy writers tend to either focus on fictional medieval to prehistoric settings or on modern day, alternative Earth settings, aka, Urban Fantasy. So there isn't much more to say about Monotheism in this regard that isn't common knowledge. It's important, perhaps as we look at religion and it's place in Sci Fi.
Predicting the future of religion is about as difficult as predicting future hairstyles. Many Sci Fi writers either continue modern day religion, ignore religion completely, or revert back to Polytheism or Animism--which may or may not make sense in a society of advanced technology. The best bet here is to remember that religion, like culture, evolves to fill a need. So ask yourself when looking at the future, fictional society you're writing about: what rules of behavior does the society need to function?
Ok, so we've covered the big, over arching theory of Cultural Functionalism. But good writing is often about the details. How about next week, we cover how speculative elements of magic and space ships might affect those details.