When you get down to it, it all has to be broken down into a set of binary switches anyway, so we might as well leverage that to work for us instead of against us.
I labor under the assumption of a modular system of metaphysics, where a thing either is, or is not possible, depending on what universe you occupy. Weighting factors that determine how strong a particular effect is would add a lot of possibilities to such a system, but don't affect my proposal on the fundamental level.
The system does not need a huge number of rules to create a combination explosion effect.
Take the Hermanubis problem I mentioned before. While the situation could be made more fine grained, there are four basic possibilities that need to be covered: 1. The two gods fuse into a single entity, incorporating some or all of the history of both characters(Beliefs can fuse gods). 2. A new god is created, leaving both of it's parent gods intact(beliefs can create gods). 3. Both gods acquire all the powers attributed to the other, but retain their identities(beliefs can alter existing gods). 4.The beliefs of the followers has no effect at all(none of the above are true).
This is essentially three rules that can be turned on or off, and effect the religions of the game in a fundamental and interesting way. Three becomes irrelevant if one or two is true, and four can only occur if the other two are false, so the only potential weirdness comes from the combination of one and two. The pros and cons of the various solutions to this conflict are too great a digression for this paragraph to continue.
A [RANDOM_METAPHYSICS] would be the best thing a religion simulator ever had.
Before you declare me completely gung ho, I implore you to note that I don't dare to suggest allowing metaphysics themselves to change over time.
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That said, I feel that grouping philosophies and religions together as sub-classes a belief system entity is perfectly reasonable, saving on code and still allowing for interesting interactions.
This does beg for giving dwarves the ability to believe more than one thing, so long as the two are not mutually exclusive, but there is only one programmer.
Just because I self-identify as a Christian doesn't mean I can't glean wisdom from Confucius and Quantum Theory. Modeling this in DF would be non-trivial, but it would also be awesome.
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Of course, all that means nothing if it doesn't have some effect on the ground. In a world with active tags like [GODS_EXIST], [MATERIAL_GODS], [INVINCIBLE_GODS], [GODS_INTEREST_IN_MORTAL_AFFAIRS:ALWAYS] and so on, that's pretty easy to do. e.g. The impious king of the elves is struck down by his tree gods and replaced with a crusader who will wreak vengeance on the hated dwarves (or die trying
).
In a world with less visible (or even non-existent) gods, religions need to be able to stand on their own and do something interesting. This is probably more important to fortress level play, than the flashy stuff, since it's something the player can shape, and it happens all the time, regardless of any effect, up above the clouds.
Individual dwarves observing, altering, joining, abandoning and creating new religions, are the meat of the thing.
There are plenty of threads, detailing suggestions on how dwarves might observe their religions. The most frequent suggestions include such things as funerals, holidays and regular temple services. These are mostly good, but I won't waste your time by repeating them here.
However, I'd like to see the religions delve into things that give them more texture, like smaller superstitions. Kiss your amulet for good luck, bestow alms on the poor to alleviate guilt, or bow every time you pass a statue, depicting your god's favored form. These things could give tiny happy or bad thoughts for doing them, or not doing them, based on a variety of factors. i.e. Urist McDoubter could get "He was pleased with himself, for not following a silly superstition," while Urist McPious might feel guilty if he was unable to fulfill one of his duties. A superstition personality trait for this sort thing might help, but then it might do more harm than good.
More important to the long term building aspect, cults need to crop up, and we need to be able to encourage or crush them, based on our personal whims. I'd like to see dwarves from inside the fortress grow into philosophers and prophets, though divine revelations, deep contemplations (perhaps just nobles and clergy), or good, old-fashioned lying. These individuals get the idea for a new religion, and start trying to convert others.
"Urist McHeretic has launched a revolutionary new school of thought!"The superstition system above could be expanded to include items like "Inquisitors should hammer heretics" and "all adherents should turn heretics over to the inquisition." Not all religions should have these, and what it takes to make one religion anathema to another is a complex issue that will need to be simplified for game purposes, but the potential for Fun makes it worthwhile.
If a cult can survive long enough to grow to a respectable size, they could start demanding whatever facilities the other religions ask for. They might need to be able to get legal protection from their hammer waving neighbors (to prevent religious conflict from being a single fork path). One way or another, whether or not the city council accidentally routes a magma flow bypass through their sanctuary will impact the world for generations.
This is a rare, but momentous opportunity and the player should have an entire toolkit of options for dealing with it. There should be more ways to interact with what may be the fulcrum point for a world's history than dumping lava on it, or not dumping lava on it.
Designating temple areas is a great start, and there are a lot of ways to add nuance to it. Larger, nicer temples mean you can support more and happier followers, who will collect more donations and recruit more clergy, leading to a nice equilibrium effect, where churches grow, until there's standing room only, and then people stop inviting their friends.
If a religion has no legally sanctioned temple, they should try to make do with covert services, held in their members' homes and workshops. This could cause unhappy thoughts, while increasing the commitment of the attendees, leading to the potential for violent revolutions, or (for peace loving religions) protest martyrdoms that attract the attention of potential converts.
HammerHand:
While religions certainly change over the number of years considered in world-gen, how many of us play a single world that long? Is it really so important to see the religions change? Is it really so important to chart that change throughout history?
Is the reason so few people play a world that long, that these types of events do not happen? Is there a reason we can't try to make at least a few of these ideas practical enough to be worth using?