The Hagakure makes a comment that if you understand the essence of a way then “a man should be able to learn about all ways and be more and more in accord with his own.”, (My apologies if that’s not a direct quote.) I’ve contemplated that phrase for a while now and I think I finally get it.
The Universe can be taken as a whole, meaning you can look at is as one solid thing with rules and strategies and whatnot. So, that means the world itself must be whole too. When people divide themselves into sects, tribes, packs, groups, sub-genres, etc they do so in accord with some rules too. Which also means that all the sub-groups have to obey rules too.
If we can understand the true base rules of our own group and see how they must reflect the true rules of the universe then we can start to see that every other sub-group you care to name has to obey the same rules. Basically, every sub-group is a mirror image of every other one. From neo-goth to high finance.