Okay, so I have been mostly thinking about Society lately. Let's start with the modern half of that category:
Individualism (Civil Liberties): represents Western societies developing during the early modern period, the rise of a middle class, private enterprise, natural rights and that kind of stuff - the opposite to the rigid feudal stratification that preceded it.
Egalitarianism/Equality (Civil Rights): represents changes in Western societies during the 20th century, equal rights for all citizens, universal suffrage, action towards economic equality, protection of minorities, multiculturalism.
For the third civic there are a couple of options:
- I think Nationalism better slots into the Organisation category as Nationhood, I'll elaborate a bit more on it below
- Not sure if Proletariat isn't too specific, but if we want something explicitly communist that isn't captured by Egalitarianism/Totalitarianism (depending on how malevolent/benevolent your state is in its application of communist ideology) I would rather move my proposed Collectivism (Labour Unions) from the Labor column here
- Totalitarianism (Psychology) should be somewhere as your explicit "going fascist" option compared to a vanilla dictatorship. I personally envision Society as the column with the strongest effects, for instance the traditional + town commerce and + specialist commerce for Individualism and Egalitarianism. In that vein, Totalitarianism could get strong effects that help you wage war or maintain a large empire at the opportunity costs of these effects
What is more interesting is the other half of the tree which should cover pre-modern societies. Like the stuff above, these civics should be more about the general idea that governs the relationships between individuals in a society, not what domain the society is focused on ("the military", "trade" etc.). I have a couple of ideas, but it's hard to make a good choice and find a fitting name, that is both descriptive and general enough:
- social status defined by birth: this is basically your feudal society, and what basically what both Caste System and Estate System were getting at in my original proposal (the former being a more extreme example of the same principle). Names: Stratification? Aristocracy? I find it hard to describe with a good word.
- social status defined by legal status: a bit of a counterpoint to the above, where there is more social mobility and you can gain a higher status and have it legally recognised. This is for instance the Roman Republic and early Empire in my mind, and what Citizenship was getting at. If we are casting the net a bit wider, and use Aristocracy above, maybe Meritocracy also works.
- another idea that is a bit orthogonal to the above so it might not fit next to them: something representing the East Asian social ideas of social duty and filial piety. What I like about this is that this could be a reasonably early civic that can still be feasible later in the game, and also contrast with Individualism.
- I think Militarism (although I prefer Martialism) could also work, and could both represent societies where the warrior class (pre modern) or a more organised military (modern period) dominates society. Especially in case Totalitarianism is not in this category.
On Organisation, I don't think categories like Unitary and Federal really work because states that use these principles seem to be so all over the place, which makes it hard to derive effects from them. I'm also not happy with an "Empire" civic, because you generally always want to be an empire, and there shouldn't be a civic especially helping you with that. "Imperial center ruling over large territories" would be better captured with something like Centralism. Nationhood also belongs into this category, as it was the innovation in how states conceive of themselves that occurred in Europe during the early modern period. Other than that, we have
- Vassalage: the state as interpersonal relationships of mutual obligation
- Thalassocracy: the state as coastal territories connected by the sea
- Colonialism: your early modern overseas colonial empire (not sure if there isn't an overlap with all of these categories, e.g. Britain could also be understood as a thalassocracy)
- City States / Confederation: a loose association of states bound by mutual treaties
- something modern that transcends the nation state, with open borders, multiculturalism, devolution/federalism and international integration
It would be cool if we had mechanisms in this category that would reward you for not expanding beyond your core (various polities considered themselves self-content over the course of history, most famously Ming and Qing China), or give different benefits for expansion for your core. But I'm not sure how we could implement that using existing game mechanics, that isn't just additional benefits on top of the inherent benefits of expansion itself.