I like stage-based theories of adult development. Kegan, Schmegan.
However, I have found a developmental pattern that is a cycle rather than a series. I think this cycle explains a lot.
The cycle goes as follows: selfish—pragmatic—philosophical. Rinse and repeat.
I will start with "philosophical" because this is what a lot of people, including me, were as teenagers.
At the philosophical stage, "this is philosophically/objectively correct", "this is inconsistent", etc, are your ultimate tools for justifying your own actions and for arguing with other people.
I was a very libertarian kid. "How dare the government tell Bill Gates he can't bundle Internet Explorer with Windows", I thought. "If I had a base on the Moon, I would satellite-beam versions of Windows with Internet Explorer down on Earth just to spit in the government's face". I was really angry about it.
I had a lot of principles. If something enraged me, I would always try to find a principle that justified it, never saying "just because it's bad" or "just because I don't like it".
At some point, I tried to figure out a universal morality. It was supposed to be based either on "reduction of suffering", or on "aiding human progress", or on "increasing variety in the universe". Nothing worked. Then I realized this was arbitrary and couldn't not be arbitrary—and had a two-week breakdown. It was in Barcelona, during a vacation with my family. I was walking around like a zombie and thinking "nothing matters, nothing matters, nothing matters". Eventually it passed. (See David Chapman on nihilism for more about such breakdowns.)
Several years later, the desire to fit everything into rules or principles has dissipated.
This happened by doing a lot of small selfish steps. Each step looked like this:
Fuck, I can't take it anymore. I know it's wrong, but I will just do [the thing I want to do].
The girlfriend example:
When my girlfriend broke up with me, I still thought "I have to be friends with her" for a year afterwards. Anything else would be a betrayal, I thought, because we were best friends and the break-up didn't change anything, so stopping being loyal to her would be a betrayal of my past self and our friendship. Even though we almost weren't talking, I still felt I had to be loyal.
One day I just said "fuck her, I don't want to be loyal to her, she hurt me". Half a year later, I stopped caring much. A year or two later, she wrote and I was able to tell her "Hey, I don't think I ever want to talk to you", even though it was scary. We haven't talked since. The thought of "I have to be loyal to her" feels like it doesn't even belong to me anymore.
The writing posts example:
In the same way, one day I decided "fuck it, I will write posts that are simply about what's on my mind and not Canonical Posts On A Specific Topic". Then I spent half a year rocking back and forth, still wanting to write "canonical posts" but also realizing that it's painful. Now I mostly don't care. I write things knowing that in a year I won't like anything I have written, and it's fine.
The Burger King example:
I used to think boycotts were completely stupid because they don't change anything. "If you want to get something done, at least organize a protest, not participate in it", I told a colleague a couple years ago. Eight months ago, I decided to boycott Burger King, but I was still feeling like I had to justify it:
"they are actually all the same", maybe, but normalizing meanness is still shitty
Nowadays I gleefully boycott Burger King without even trying to justify it.
The sex example:
I used to have a very puritanical attitude to sex—"yeah, I want it, but it's still inherently bad and everyone who doesn't agree is an animal". At some point I decided that—fuck it, I'll be an animal then because otherwise I won't ever be able to enjoy sex. Again, I spent some time rocking back and forth, and eventually arrived at "mostly don't care".
At some point you start noticing:
Huh, I thought I was being selfish when I decided to do whatever I wanted, but this is actually good for others. I had better keep going!
At the most basic level, being happy is good for others around you, because they don't have to deal with the unhappy you. They can use your support, because now you have more resources. They can learn from you. If you manage to get a good life, people can look at you, imitate you, and get good lives as well.
Now let's look at concrete examples.
The girlfriend example:
I thought I was being good by being loyal, but in reality it turns out that learning from something is much easier once it's over. You can't learn from a failed relationship before you both are officially done with each other.
So, I was preventing her and myself from learning from the experience.
The "writing posts" example:
I only arrive at good thoughts after writing about random thoughts first, so it turns out that if I never write about random things, I don't have a chance of eventually writing something that will be useful to people.
Plus, people are able to learn even from random rambles. At the very least, they can inspired by them and have their own thoughts. Huh.
Participating in a collective of people trying to figure things out is cool and useful to everyone. If you don't shut yourself in a room trying to come up with original insights, everyone will actually get to original insights sooner.
The Burger King example:
Boycotting is often a good act. For instance, boycotting Burger King might be the first step towards deciding not to eat at chain restaurants altogether, which would lead to learning about small burger places in your area and exploring them, which is probably good for you because a) you eat better burgers, b) you have more socializing opportunities, c) you know the area slightly better and thus are a more interesting person.
However, the thing is: even if you don't do any of that, by publicly boycotting Burger King you show other people who have you in their lives that boycotting things is allowed and feasible. People don't merely learn by imitation, people live by imitation. So, by doing something that is right but pointless, you make it slightly easier for others to do something that is right but pointless—and in their case it might turn out not to be pointless after all.
The sex example:
It turns out that if you don't think sex is wrong and shameful, people will enjoy sex with you more. QED.
Eventually you start trying to spread those good things that you've noticed.
This is when observations become: principles, a framework, a theory, a self-help book, a list of twelve rules for life, or whatever else.
Ahem.
The point I wanted to make is that you can be at different stages of the cycle for different things/ideas. Selfish about some and philosophical about the others.
Each stage of the cycle is useful. The philosophical stage is useful, if anything, because it lets you convey your experience to other people. The selfish stage is useful because it lets you do a reset on what you have learned, and not get stuck in local maxima. The pragmatic stage is useful because it helps you do better after you've done a reset.
The point of this post isn't to get you through the cycle faster.
The point of this post is to let you see how the cycle works, and stop fighting with others when they approach something from a different point in the cycle. It might be useful for them.
And there is another point. If you are stuck in some part of the cycle, seeing the cycle might help you move forward.