In my everyday job, I think about simulations a lot. Specifically, I think about how complex patterns arise from simple rules and the interactions of individual actors. There are general rules in how seemingly complex systems reach stability, and many of these rules are due to bottom-up interactions. Previous iterations of the Civilization game franchise have felt like bottom-up simulations to me: the size of your empire was partly a function of how rapidly you could move your troops (which could be altered by building roads or railroads, upgrading units, etc). If you couldn't defend your boarders, some AI would take cities from you until you reached a point that you could maintain your boarders.[1] In more recent versions of the Civilization games, concepts of "city happiness" played a role in that an unhappy city could choose to "flip" and join a different civilization.
As I have been watching Civ V AI-only "games"[2], I've been wondering why I just wasn't able to feel as immersed in the games. I still play Civ IV: Beyond the Sword, so I haven't lost my love of the genre. Maybe a part of why I am not taken with Civ V is that some of the game elements are top-down limitations rather than bottom-up emergent properties.
Civ V introduced the concept of civilization-wide happiness. If you have negative happiness in your civilization, that slows (or can stop) population growth in cities, slows production, and results in combat penalties for your troops.
The red text and the little angry face show sources of unhappiness in this civilization. Note that there is a total of nine unhappiness for cities, and 36 unhappiness for population. Just to be clear, the entire civilization is unhappy that there are too many cities. Quoting from a guide:
Each City you found will produce 3 Unhappiness, and +1 per unit of Population. So, founding a City will immediately produce 4 Unhappiness. As it grows, it will produce more and more Unhappiness, +1 per new Citizen.This is a great example of top-down regulation of a simulation's behaviour. This game mechanic effectively means that the maximum size of a civilization is limited unless the player or AI works very hard at building things that promote happiness, have good relations with city states (a special type of AI in the game), get certain luxuries, etc.
To be clear, I understand this is just a game. As a game mechanic, this sort of thing works well and fixes a problem that older versions of Civilization had. Specifically, the emergence of a Superpower in the game. In older versions of the game, the more cities a player/AI had, the more troops it could produce, and the more cities it could conquer, so it could produce more troops....[3]
The top-down control on civilization size has a drawback: it removes the organic feel of a spreading group of humans. Humans have spread to every corner of the globe that can support life. We didn't stop because we had too many tribes. If you set up an AI-only game with a single civilization and no winning conditions, that AI will expand to a certain size and then just stop, leaving the rest of the game-world empty.
What would make Civ V more of a bottom-up simulation? In Civ 2, there was a game mechanic where, if you managed to capture a more powerful civilization's capital and it was unable to instantly build a capital in another city, civil war would happen and the AI you were fighting would become two different AI controlled civilizations. As far as I know there was nothing similar in Civ III or Civ IV, but there was a mod made for Civ IV that allowed unhappy cities to revolt and form a brand new civilization.
Thanks to the modding community, there are mods for Civ V that accomplish similar things, though the rebellious cities form City States, which are special AI civilizations called Minor Civilizations that do not make settlers, so they do not expand their territory. From my perspective, it would be more interesting if the cities become new Major Civilizations, but at least there is a mod that allows Minor Civilizations to build and use settlers so they can expand.
It has me wondering whether a combination of
- Removing happiness penalties for founding/having cities (mod)
- Using the Revolutions mod to allow individual cities that are unhappy or influenced by other civilizations to rebel and either start their own civilization or join another civilization
- The City State Settlers mod to allow those newly generated Minor Civilizations to make settlers and expand
would result in an AI-only game where a single AI would result in the game-world being completely settled by a diverse number of civilizations. Many from one. Ex uno multa? My very own Tower of Babel simulation.
[1] This is not entirely accurate, since what actually happens is a sort of armed boarder stand-off or crushing defeat where a massive stack of units overwhelms the enemy positions.
[2] Let's be honest and just call them "simulations".
[3] In Civ I, this was slightly offset by the need to feed your troops. Food for your troops came from the city it was produced in. This was a fun mechanic that I miss. You could get rid of troops by "interrupting their supply line" by attacking the city that was feeding them, destroying their ability to harvest food, or capturing the city. Later versions required that you pay money to support troops, but a successful economy let you fiend pretty big armies...sort of like in real-life.
